The HobbitHouse Ilustrated Glossary of Woodworking terms
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gable --- The triangular portion of a wall between the edges of a roof that slopes upwards from two sides. Expressed another way, it is the portion of wall at the end of a building that is under the inverted "V" formed by two roof slopes. The same construct at the end of a gable dormer is also a gable. Examples:



gable dormer --- a dormer that has a gable.Examples:



gable louver --- A louver that is put into a gable so as to provide ventilation into an attic. Examples:



gable roof --- Traditional roof style; two slanted roof planes of equal size meeting at a ridge line. Note that the word gable alone does not refer to such a roof but rather to the wall section contained between the two sections of roof. Compare/contrast to gambrel roof. Example:



galvanic corrosion --- A process that causes corrosion in dissimilar metals that are in contact with each other in the presence of salt water (or certain other chemicals); the combination of metals and electrolyte creates an electronic process which separates material off of one of the metallic surfaces. Non-conducting phenolic washers are used to prevent this when, for example, steel screws are used in aluminum blocks.

gambrel roof --- A roof somewhat like a gable roof except that each of the two roof planes of the gable roof is split into two planes with the one closest to the walls of the building at a very steep angle (not too far off of vertical) and the inner plane that meets the ridge beam at an angle similar to that of a gable roof. This constructions provides more internal space than does a gable roof and also the sharp slope of the outer planes inhibits snow buildup on the roof. Gambrel roofs are common on barns in particular. Compare/contrast to gable roof. Example:



gamma --- see color terms

gang mill --- A saw millin which several saws make parallel cuts as part of a sash gang.

gap --- (1) An opening between two pieces of wood. Usually, the implication is that there should not be such an opening. For example, gaps in the inner plies of plywood are not desirable. However, it is possible to have a situation where a gap is desirable, so the term does not automatically imply a bad thing.
gap --- (2) see bed gap

gasket --- A flat strip of non-metallic material that is used to fill the space, usually in a channel around the rim, between two mating objects (usually metal), with the purpose of preventing leakage. The gasket allows for slightly less precise machining of parts because it compresses slightly when the objects are mated and thus makes a good seal even if the objects do not mate with total precision. Motors, in woodworking tools as elsewhere, often use gaskets to prevent internal lubricants from leaking out.

gate hook --- [also gatehook] A type of hooking system most often used to keep screen doors closed. It consists of an eye hook on each end and a long, specially shaped cup hook attached to one of them and fitting into the other. Also called a "hook and eye". Examples:



gauge --- A measurement of wire diameter; the higher the gauge number, the thinner the wire.

G clamp --- synonymous with C clamp

gear puller --- A very clever tool that allows one to remove belt drive pullys and gear rings from shafts by applying a uniform force on two or three evenly spaced positions around its rim, which you can't do with a pry bar. The tool has two or three curved prongs with hooked ends and hinged so that they can be adjusted onto the gear's rim. Then there is a threaded center shaft that pushes against the end of the shaft on which the gear is affixed and when you turn it, it puts pressure on the prongs, which in turn pull on the gear ring. Most gear pullers have hooks on both ends of the prongs, facing opposite directions, so that you can remove the center shaft, reverse it, and then pull from the inside of a gear ring if that's needed. Some years back I wasn't able to get a slightly rusted belt drive pully off of the drive shaft on my floor model belt sander. After trying screwdrivers and hammers and pry bars and really loud curse words, I went out and bought a gear puller and popped the pully right off without the slightest trouble. Examples (all but one of these are reversible; the one in the upper left is set up to pull from the inside, the rest are set up to pull from the outside):



gelled --- The condition of a finishing agent which has thickened to a jelly-like consistency making it unusable.

general purpose saw blade --- synonymous with combination saw blade

genus --- see taxonomy for a discussion

ghost --- see ghost outline

ghost outline --- When turning objects on a lathe, before the outer rim becomes completely round, there are projections at various places around the rim and these can be faintly seen at the edges of the turning workpiece; this is referred to as a ghost or ghost outline. Using the ghost can be very helpful in determining exactly how to attack the edge with the lathe tool to continue the rounding of the edge but without being overly aggressive and causing chip-out while doing an interrupted cut.

Gibraltar board --- synonymous with drywall

gimlet --- a hand tool for drilling small holes in wood. It has a handle at 90 degrees to a metal rod that ends in a pointed spiral cutting edge that is sometimes just a single straight or near-straight flute. Gimlets are for small holes up to about 1/4" and when larger holes are required, a similar tool, the bar auger, is used. Examples:



girder --- A main horizontal or near horizontal structural member that supports vertical loads. Generally a girder is larger than a beam but the distinction as to when size changes the name of something from beam to girder is vague.

girder pocket --- A recess in a foundation wall to support a girder such as one which in turn supports floor joists. (this is one of those situations where you can get into religious arguments about whether the girder is a girder or a beam. In the illustration below, part A shows a girder sitting in a girder pocket in a foundation wall and part D shows it closer up where you can see that the girder is made up of three 2x12's. Part E shows it transparent so you can see that the back of the girder does not quite touch the foundation wall (this is to prevent wicking of condensed moisture from the wall into the end grain of the girder planks. The notched strip along the top of the wall is the sill plate. The other views (B=side, C=top, F=front) show that the top of the girder is flush with the top of the sill plate, the sides of the girder don't quite touch the sides of the pocket, and the sill plate is notched so that the girder can move fairly far into the pocket but not all the way to the back of the pocket. Example:



girdling --- a method of killing trees by cutting a slot all the way around the tree through the bark and into the bole, thus interrupting the flow of water and nutrients. See also frilling

girth --- The distance around a tree; the circumference. The diameter of a tree is commonly taken as the diameter at breast height (DBH) but I have not seen such a standard for girth; presumably it is the circumference at breast height

glass and tile drill bit --- An arrow-head shaped drill bit that is used to cut holes in glass and ceramic. Examples:



glass cutting drill bit --- see glass and tile drill bit

glass door hinge --- A type of pivot hinge designed specifically for use with glass doors. What accomodates glass doors so well is a "U" cross-sectioned bracket that holds the glass. Sometimes screws are used to hold the bracket, but more often it is glued to the glass (or installed as a pressure fit with high-friction rubber) so as to avoid having to drill screw holes in the glass. The (hinge) pin then protrudes directly up or down into the frame. I have seen even very heavy full-sized glass doors mounted with this technique, but it is more commonly used in display cases and home entertainment centers. Examples:



glazing bar --- A molded strip of wood that is both decorative and functional, used to hold the panes of glass in a window (assisted by glazing putty. Where two such bars cross, they are normally mated with a glazing bar half lap joint. These days, aluminum glazing bars are often used, so I have include some in the examples below. Examples:



glazing bar half lap --- A crossed half lap joint in a glazing bar. This is a complex joint and showing it reasonably accurately was one of the biggest challenges of the drawings I did for this glossary. Example:



glazing putty --- A dough-like caulking compound that is used to secure panes of glass by putting a "bead" (actually a triangular cross section strip) between the glass and the glazing bar. Not used in modern windows which tend to be double paned and have aluminum glazing bars with glass capture mechanisms that do not require putty. Very old glazing putty can often be seen with cracks that occur as the putty dries out and shrinks. I have it anecdotally that modern silicone caulking compounds are good replacements. See glazing bar for an illustration.

gloss --- [also sheen] The reflectivity of a coating. see finish rating

glue --- Originally used to describe early adhesives which were a gelatinous goo made from animal parts (hide, tendon, cartilage, bone), which are now called hide glue. The term is now commonly used as synonymous with adhesive which is a more general term. Strictly speaking, glue is not synonymous with adhesive, but does include more modern compounds than just hide glue. Some of these are:NOTE: INCOMPLETE SECTION --- most terms below are not yet defined

glue block --- A flat piece of wood that is glued directly (or indirectly with a Kraft paper separator) to the back of a workpiece that is going to be face turned and is then itself mounted on a faceplate; the glue block avoids getting screw holes in the workpiece.

glue joint --- (1) A joint that uses adhesive instead of nails or screws. Compare/contrast to dry joint.
glue joint --- (2) The location at which two objects are held together with glue.
glue joint --- (3) Although any joint that is fastened with glue can be called a glue joint, the term more specifically means a joint that has been given more surface area by some manner of cutting or routing, so as to give the glue more holding area. There are numerous router bits that serve this purpose; here is one example, and if you look carefully you will see that this bit has a characteristic that is typical of such bits which is that if you line up the bit and the plank just right, you can make both passes on the same bit. That is, you cut two planks on their edges and then you flip one of them over and it fits into the other with both faces flush. In addition to providing more surface area for the glue, this kind of routing also provides greatly added shear strength at the joint.



glue laminated beams --- see glulam

glue laminated timber --- see glulam

glueline --- The adhesive joint formed between veneers in a plywood panel or between face veneers and core in a composite panel, or between two boards in a joint. Highly visible gluelines in joints are considered poor cabinetry.

glue nailed --- synonymous with nail glued

glulam --- Short for glued-laminated structural timber. These are large beams and girders fabricated by bonding layers of selected lumber with strong, durable adhesives. This is done with all sub-members having their grain aligned in the same direction, unlike plywood which has alternating grain directions. End and edge jointing allow production of longer and wider structural wood members than are normally available from raw timber, and bending while gluing allows for construction of curved structural members that would not be possible with raw timber. Also, the process allows large members to be created from small trees. Glulam members may be used purely for strength, but may also be used in exposed positions for both strength and for the blatant impression of strength that they convey. Sometimes really large girders are made of glulam because although they are much larger than an equal-strength steel beam, they weigh less, which is a structural advantage. Here are some examples:



goblet --- A somewhat vague term, which I have seen used to describe turned objects that have the shape of anything from a wine glass (sides pretty much straight up after curving away from the stem) to what I think of as a goblet shape, which is more like a cognac snifter. Compare/contrast to other lathe turnings. Examples:



going --- As regards woodworking, this term refers to the depth of one stair tread, not measured on the tread itself but rather horizontally from one riser to the next riser, so if the tread projects out over the riser, that projection is not counted as part of the going. The term is also used to refer to the combined depth of a flight of stairs as measured from the face of the first riser, horizontally, to the face of the last riser. Also called the "run". Compare/contrast to rise.

golden rectangle --- A rectangle which has its ratio of length to width equal to about 1.618 (the so-called "golden ratio"). This is supposedly the rectangle which is most pleasing to the eye and has been used since antiquity in art. Technically, it is a rectangle such that its length and width satisfy the equation L/W = (L+W)/L, which, if you solve it, turns out to be (1 + sqrt 5)/2, or about 1.618.

good one side --- Plywood with one side patched (usually with boat patches) so as to be solid. This good side is also usually sanded smooth. The other side will be unsanded and may (and usually will) have open knot holes.

gooseneck cabinet scraper --- A cabinet scraper that has a French curve shape. Examples:



gouge --- [verb] To cut wood with the kind of tool described below, and by extension, to make any sort of channel-like cut into wood, whether deliberately or by accident. Accidental gouges are unhappy occurances for a turner, as they can cause considerable rework to remove and can even ruin a piece under some circumstances.
gouge --- [noun] A sharp-wedge-edged tool with a curved cutting edge. Gouges fall into two distinct types, lathe (or "turning") gouges and carving gouges. The sister tool, the chisel, is a straight sharp-wedge-edged tool. It is the straight vs curved edge that makes the distinction between the two. Chisels also come in those two flavors, but also has a third that does not exist in gouges and that is the joinery chisel. See also chisels vs gouges.


gouges vs chisels --- see chisels vs gouges

GPH --- Gallons Per Hour; a measure of the amount of water flowing through a fixture or pipe.

GPM --- Gallons Per Minute; a measure of the amount of water flowing through a fixture or pipe.

grade --- (1) synonymous with slope
grade --- (2) "rating", as in "high grade steel". The results of the process of grading. Manufactured wood products (see composite material often have a grade stamp that specifically states the grade of the material. Panels in particular have an extensive grading system established by the APA, which gives letter grades of N, A, B, C-Plugged, C and D to the quality of the surface veneer.

grademark --- synonymous with grade stamp

grade stamp --- An inked marking put on lumber or composite materials to show the important characteristics, mill information, general rating of quality, and so forth (called the grade)

grading --- The process of classifying lumber, veneer, flooring, and composite materials according to characteristics and quality standards for each item, as set by appropriate organizations such as the APA. Grading can take into account the composition, strength, chemical nature, size, density, surface type, type and size of acceptable flaws (such as knots), and many other characteristics of the material.

graft line --- Some woods, notably pistachio and walnut are often grafted. Walnut, for example, is generally grafted with English walnut going on top of claro walnut, because English walnut produces the best walnuts for use in cooking but claro walnut is a more hearty stock and is more resistant to disease. When woods are grafted, the resulting "graft line" can be quite striking visually and also strong mechanically and is much favored by makers of rustic benches and gun stocks. In pistachi in particular, the graft line often causes an area where rather than the normal vertical line in the tree that separates the sapwood from the heartwood, the line is horizontal, running against the grain in a way that creates quite a striking visual effect. Examples in both walnut and pistachio:



grain
A note about "grain" and "figure". These terms are sometimes used interchangeably in a way that I believe to be incorrect. In this glossary, I take a point of view which I believe is the "correct" one, but I want to acknowledge that it is opposed to that taken by some, including a man whom I consider very much my better in regards to knowledge of wood and that is Dr. Bruce Hoadley who has written two books that are widely, and I believe appropriately, considered to be the definitive works in their field. These are "Identifying Wood" and "Understanding Wood". On this particular issue, I have a strong and supportable reason for differing with Dr. Hoadley.

For a full discussion of the two points of view, and the statistics that validate my own point of view, click here: figure vs grain. I don't put the whole thing right here because this box is already too big.

Had this difference of opinion been with anyone other than Dr. Hoadley, I would simply have ignored them and gone on my way and would not have subjected my readers to this diatribe. However, I think that regarding ANY other information about wood, anyone who ignores Dr. Hoadley is being foolish. As young people say these days, when it comes to knowledge about wood, "He da man".

grain --- The annual growth rings and pores of wood. See box directly above. There are a number of terms commonly used to describe various characteristics of the pores and their effect on the wood. Because of (1) the use of the terms "open" and "closed" and "close", (2) the use of tight and close, and (3) the two different characteristic sets of open/closed and closely/widely spaced, some of these terms get damnably confusing when you see them all together but they do make sense once you sort them out. Compiling this set of terms DID make my head hurt. They are shown directly below the composite pic below which shows the fundamental characteristics of grain (ring spacing and pore size).

Other grain-related terms:

grain direction --- The direction in which the dominating, elongated fibers or cells lie in the structure of wood.

grain pop --- see pop

grain raising --- The swelling and raising of surface wood fibers caused by absorption of water or a finishing agent. Some wood finishes will cause grain raising upon application of the first coat and so the wood has to be sanded and/or buffed before other coats are applied.

grainy --- a loose term, generally meaning coarse grained.

granules --- Finely crushed rock that is coated with a ceramic coating, fired, and used as top surface on shingles.

gravity guard --- A blade or cutter guard that is raised by passage of the work, then drops back under its own weight; very common on table saws.

gray stain --- An oxidization reaction in some woods, primarily the sapwoods of Southern hardwood trees, and particularly hackberry. It is a process very like that which causes apple insides to turn brown pretty quickly after exposure to air. As nearly as I can tell, there's nothing you can do about it once it appears but it can be avoided by getting the lumber into a drying kiln within hours of its having been sawed.

green --- see green wood

green condition --- Wood that has been seasoned but subsequently submersed in water is not green wood but is said to be in green condition because its moisture content will be similar to that of green wood.

green knot --- Apparently, and I'm not sure because I have not found a definition anywhere but have only seen the term used in context, this is synonymous with red knot

green lumber --- synonymous with green wood

green weight --- The weight of wood when freshly harvested, when it has the same moisture content as the standing timber.

green wood --- When wood is first cut, it is called green or unseasoned. At this point it has a very high moisture content (usually over 25% and frequently WAY over 25%) and if that content is not reduced in a controlled way, the wood will almost certainly suffer drying defects. Also, the wood cannot be put into service (that is, cut up and used for projects) in the green state because the subsequent loss of moisture from cut pieces will definitely cause drying defects. The process of removing the moisture in a properly controlled way is either air drying or kiln drying and both of these processes are called seasoning or drying. For softwoods less than 5 inches thick, "green" has the specific meaning of having moisture content above 19%.

grillage --- A system of orthogonal elements, usually beams or trusses, acting together to spread a heavy load out over a large area.

grind --- [verb] In regards to woodworking, this refers to the action of removing some of the surface of a metal object by an abrading action, generally by a grinding wheel or sharpening stone. See also grind / hone / polish.
grind --- [noun] The shape of a cross section of a blade showing the shape of the grinding edge. For example, a tooth on a a circular saw blade is said to have a "flat tooth grind" if the top (cutting) edge of the tooth is perpendicular to the body of the blade and a fingernail grind is a particular form of grind on a lathe tool

Grind related terms:

grind angle --- The angle from the shaft of a tool to the bevel on the working edge.

grinding --- see grind

grinding wheel --- A natural or artificial stone in the shape of a narrow cylinder that is mounted on an axle and powered in some way so that it rotates. As it rotates, metal objects are held against either the rim or the side of the wheel and are thus ground down for the purpose of either removing material or sharpening an edge. Grinding wheels used as sharpening stones are traditionally called grindstones. Examples:



grinding wheel dresser --- A device for dressing the surface of a grinding wheel. The most common of these is the star wheel dresser.

grindstone --- [and, rarely, "grind stone"] A natural grinding wheel that is specifically used for sharpening. These have been around for thousands of years in forms that were powered by hand cranks or foot pedals. Today one more likely would use a bench grinder or specialty (and often proprietary) sharpening system. Examples:



grit --- As regards woodworking, this term refers to the size of the particles used in sandpaper and sharpening stones, and is expressed in a number which represents the quantity of particles in one square inch (actually, with sandpaper it's slightly more complicate than that). The aggressiveness of the action of sandpaper depends primarily on two things, the grit number and whether it is open coat or closed coat (see discussion with open coat), although the type of material used also has an impact. Extremely rough ("coarse") sandpaper generally starts around 35 grit. A 35-grit open coat belt on a floor model belt sander will chew through the butt end of a pine 2x4 amazingly quickly. A medium grit is 100 to 360 or so and above that is fine grit, going all the way up to 6000 grit (which is generally only used with metal). Sanding wood with anything above about 2000 grit is likely to be a waste of time. To the fingers, 4000 grit feels more like silk than sandpaper. I used to use 600 grit on my bowls but finally realized that I was wasting my time since after the application of a couple of coats of polyurethane finish, I could no longer tell whether the final sanding had been done with 220 grit or 600 grit, so I now stop at 220 grit. When I am finishing wood for pics for my wood id web site, I use 100 grit, but this DOES sometimes leave the surface a little rough; I really should use 400 or even 600. Sharpening stones can have a somewhat different action for a given grit size depending on what the stone is made of but with one exception, sharpening stones do not have open and closed coats; they are all "closed coat" materials. The exception is the diamond sharpening stone.

groove --- (1)[noun] A long narrow channel cut in wood. In wood carving, this might be any cross section including "V" shaped, "U" shaped, rectangular, and others; in wood joint terms, it has a rectangular cross section and is also called a dado, and if it is cut parallel to the grain, it can also be called a plough cut, and if cut along the edge or end, it is called a rabbet. For a full explication of joinery groove terms, see JOINERY GROOVES. See also tongue and groove.
groove --- (2)[noun] A surface treatment on a textured plywood panel in which a series of narrow, parallel channels, usually "V" shaped, are cut into the surface so that the panel looks like a series of mated planks.
groove --- (3)[verb] To cut a channel of the type(s) described in (1) and (2) above.

gross lumber tally --- lumber measured in board feet when freshly cut and before kiln drying (which will shrink the wood by a variable amount depending on the species and thus reduce the bf count). Compare/contrast to net lumber tally.

ground --- (1) In 3-wire electrical connections, one wire is the "ground" wire that is connected to the earth so as to avoid static electrical charge in devices. Also called "earth ground".
ground --- (2) The earth; soil; the stuff in your back yard (unless you live in Manhattan, in which case, that stuff is called concrete.
ground --- (3) Reduced in size, or modified in shape, by a process of grinding.

ground wood chips --- Ground wood is usually produced from a hammer mill or tub grinder and appears shredded and fibrous with irregular sizes, depending on the screen or grate used. Ground wood is easily distinguished by its geometry from wood chips produced from mill chipper or a whole tree chipper. Chips from a whole tree chipper or a mill chipper appear square and evenly cut rather than fibrous and irregular. See also ground wood paper.

ground wood paper --- Newsprint and other inexpensive paper made from pulp created when wood chips are ground mechanically rather than refined chemically.

groundwork --- synonymous with substrate

group number --- Plywoodis manufactured from over 70 species of softwood. These species are classified according to strength and stiffness into 5 groups, with group 1 woods the strongest. The group number of a particular panel is determined by the weakest (highest numbered) species used for the face and back (except for some thin panels where strength parallel to face grain is unimportant).

grout --- (1) A mix of cement, sand, small aggregate and water, that is used to fill the cells of hollow concrete blocks to lock in steel reinforcing rods. Also sometimes used just to fill in cracks and crevices in masonry.
grout --- A thin plaster for finishing walls and ceilings.

growth rings --- synonymous with annual growth rings

grub screw --- synonymous with set screw

gudgeon --- The "hole" part of a pintle and gudgeon hinge. When used on ships' rudders, the gudgeon is almost always a U-shaped strap with the hole a the middle of the U, but in other application, other types are used. Examples:



guide bearing --- see roller bearing

gullet --- a relief area cut in front of the tooth on a saw blade in order to provide a temporary place to store the material cut away by the tooth on each pass of the blade so that it doesn't jam up against the blade but has a place to sit, uncompressed, before the tooth clears the workpiece and the material can flip out of the blade area. This helps prevent blade overheating. The design of the gullet must be done keeping in mind such factors as the type of material being cut, the type of cut (ripcut or crosscut and smooth or rough), the expected speed of the cut and the type of tooth design including the pitch or hook angle of the teeth. A rip saw blade, for example, is designed to cut very quickly along the grain of the wood and has fewer teeth and a large gullet to aid in the removal of sawdust. A crosscut blade on the other hand will have a smoother, slower cut against the grain, therefore having more teeth and a smaller gullet.



gum --- Technically this term should be limited to a vegetable secretion of many trees or plants that hardens when it exudes, and is soluble in water, but in common use it is also applied to exudations that are not soluble in water and are actually resins, not gums.

gum canal --- A tubular intercellular cavity in wood which may contain gums, mucilage, resins, or latex depending upon the species.

gum patch --- A particular form of gum pocket that commonly forms in American black cherry. It sometime looks a little like black-line spalting and sometimes looks like bark inclusion, but usually can be distinguished as gum. Example:



gum pocket --- A well-defined opening between annual growth rings, that either contains gum or that contains evidence of prior gum accumulation.

gum seam --- A check or shake filled with gum.

gum streak --- synonymous with pitch streak

gum vein --- synonymous with gum canal

gusset --- see gusset plate

gusset plate --- [also just "gusset"] Large-area sections of steel or plywood, nailed or bolted to adjacent timber members in a truss or other frame structure for added strength. Gusset plates may be applied to one or both sides of a node where truss members meet. Examples:



gutter --- A horizontal trough that collects rainwater along the length of a roof at the level of the eaves. Also called an "eave trough". Gutters are normally attached with gutter spikes. Examples:



gutter spike --- This is a long nail (usually about 7" to 8" long and up to 3/8" in diameter, although more like 1/4" is more common) that is specifically used to install roof gutters. As shown in the composite pic below, the nail is put into the outer hole in the gutter, then inserted through the ferrule and then through the inner hole in the gutter and driven into the fascia. The ferrule prevents the nail from being hammered in so far that it bends the gutter. Generally, these are quite similar to common nails in appearance, but the end of the shank may be ridged for better holding power. There are long screws that are also used specifically for the same job for even more holding power. Examples:



guy wire --- A cable (wire or rope) that is used to brace or add structural stability to something such as a sign or tent or telephone pole. Guy wires are braced at one end on the ground on on a building and are attached on the other end to the moveable object. They frequently have turnbuckles that allow adjustment of their tension.

gymnosperm --- A botanical classification for plants whose seeds are not enclosed in ovaries. Within this group are all softwood tree species. They usually have cones; immature cones are fleshy, while mature cones tend to be dry and woody. Some cones are round and ball like when mature, such as some cedars, hemlocks, yews, and others. They tend to have needles instead of broad leaves, with few exceptions, such as Ginkgo, and they tend to be evergreen, although some (e.g. bald cypress) do drop their leaves in the fall, and many hardwoods (e.g. some oaks) in both tropical and temperate climates are evergreen, so leaves alone don't make the distinction between hardwoods and softwoods. Contrast with angiosperm.

gypsum board --- synonymous with drywall

hacksaw --- A saw with a blade that is put under tension in a simple frame, usually by a finger turnscrew, that allows a simple and quick blade change. The saw is used for cutting metal, plastic, and so forth but not wood. There are several different blade types available for cutting different types and thicknesses of metal and other materials. All have a pistol grip and there may or may not be a bit of a grip on the other end as well, to facilitate two-handed use. I recommend the kind with the extra grip because even though the saw is designed for one-hand use, there are rare occasions when it is useful to be able to get the extra strength and control provided by a second hand. Examples:



haft --- The handle of a weapon or tool. Also called the "helve", although I believe that term is obsolete or at least obsolescent.

hairline --- A thin, perceptible line showing at the joint of two pieces of wood or as a crack in an otherwise solid plank.

half blind --- see half blind joint

half blind angled dovetailed full lap --- see angled dovetailed full lap

half blind angled dovetailed half lap --- see angled dovetailed half lap

half blind angled full lap --- see angled full lap

half blind angled half lap --- see angled half lap

half blind angled keyed dovetail full lap --- see angled keyed dovetail full lap

half blind angled keyed dovetail half lap --- see angled keyed dovetail half lap

half blind bridle joint --- see bridle joint

half blind corner full lap --- see corner full lap

half blind corner half lap --- see corner full lap

half blind dado --- A dado joint where the groove does not go all the way from one edge of the face to the other edge but rather is stopped before reaching one edge. Also called a "stopped" dado. The cut can go along the grain or across the grain, but if it goes along the grain, there is a more specific name, plough. Compare/contrast to blind dado and through dado. Examples:



half blind dovetail --- A dovetail joint where either the pins or the tails do not go all the way through one side of the mating pieces. Usually the construction is such that the pins go through and the tails do not, but this is not always the case. This half blind construction gives the strength of a dovetail but allows one face to stay clear so that a drawer front, for example, can show an unblemished face.

The terminology here is widely misused in that this joint, that is, the half blind dovetail described in this entry and pictured below, is frequently called a "blind dovetail", which is not technically correct. There IS a true blind dovetail, as I present in this glossary, but it is so onerous to construct and so infrequently used, that the terminology has slipped and the term blind is often used for what is really the half blind dovetail. Compare/contrast to blind dovetail and through dovetail joint. Examples:



half blind dovetail bridle joint --- see dovetail bridle joint

half blind dovetailed full lap --- See dovetailed fulllap

half blind dovetailed half lap --- See dovetailed half lap

half blind edge full lap --- see edge full lap

half blind edge half lap --- see edge half lap

half blind edge rabbet --- see edge rabbet joint

half blind end rabbet --- see end rabbet joint

half blind full lap --- see full lap joint

half blind half lap --- see half lap joint

half blind joint --- Describes a joint, such as a dado joint, which could go from one edge of a board to the other but instead is stopped before reaching one edge. This is half way between a blind joint which doesn't go all the way to either edge and through joint which goes all the way to both edges. It is also called a stopped joint. Examples of all three in a dado joint to illustrate the difference:



half blind keyed dovetail full lap --- see keyed dovetail full lap

half blind keyed dovetail half lap --- see keyed dovetail half lap

half blind sliding dovetail --- A sliding dovetail joint in which the slot is not cut all the way across the plank that it is in, but rather stops just before the edge on one side, thus making for a hidden joint when seen from the front (but obviously a dovetail when seen from the rear). Also called a "stopped" sliding dovetail and a "shouldered" sliding dovetail. Compare/contrast to through sliding dovetail. Examples:



half blind twin bridle joint --- see twin bridle joint

half lap joint --- A joint style in which two planks of equal thickness cross each other, fully or partially, and grooves are cut in both so that their face surfaces are flush when they mate. There are numerous types of half lap joints, depending on whether the planks cross totally or partially, whether they cross at right angles or some other angle, whether they cross in the middle or at the corners, and so forth. Many types of half lap joints are discussed and illustrated in this glossary under the terms listed below. The basic forms are illustrated directly below the list. Compare/contrast to full lap joint.



half overlay face frame door --- see face frame door

half round --- molding which resembles a long cylinder cut in half lengthwise.

half sheet --- see sandpaper

half sheet sander --- A power sander that uses 1/2 of a sheet of sandpaper (thus the name). This is the big brother of the quarter sheet sander but unlike the quartersheet sander, these are not always orbital sanders. Sometimes they ARE orbital sanders but they may also use of form of oscillation that only goes back and forth. Compare/contrast to other forms of power sander. Examples:



halved joint --- A joint that is basically a box joint but with one huge finger and one huge open space on the end of each plank. Because it is visually striking, this technique is sometimes used to make boxes. As shown in the examples below, the box can be just rectangular but more often the sides are shaped into a gentle curve. Because almost all of the glue surface in this joint is end grain to face grain, it is fairly weak and so, although I don't show it in the examples below, it is very common for there to be decorative (but also functional of course) pins inserted into each of the fingers. Examples:



hammer --- [verb] To strike something with most any object with the purpose of driving the thing struck into another object, or of changing the shape of the struck object, or of loosening it, or any number of other reasons. The prototypical example is, of course, hitting a nail with a hammer [see noun definition below].
hammer --- [noun] A metal striking tool with a wooden or plastic or metal handle (and there are some powered devices that carry the name hammer). This is arguably the first tool used by humans, since a plain old rock will often make a passable hammer. There are so many varieties now that I don't know if I'll be able to cover them all, but I'll make a try. When most people say "hammer", what they mean is claw hammer since that is by far the most commonly used type. Types of hammers: NOTE: INCOMPLETE SECTION --- some terms below are not yet defined and some terms are not yet included

hammer drill --- A version of the power drill that has a specially designed clutch that provides an in/out motion in addition to the normal rotary motion of the drill. This is designed for use with hard brittle materials such as concrete and brick and is normally used in conjunction with a carbide tip drill bit designed for use with masonry. The hammering in/out motion breaks up the material much more effectively than the rotary action alone would. The distance of in/out travel is very small but the rate is high (dozens per second). These drills are heavier than normal power drills. On most, the in/out motion can be turned off thus allowing the drill to be used in the normal manner. There are extra heavy duty versions, of a different internal construction, that are called rotary hammers, rather than hammer drills, to emphasize the "hammer" part of their functionality. Examples:



hammer mill --- A crushing mechanism, various kinds of which are used in various industries including the wood industry. It reduces material to small pieces by means of rotating hammers, which create a smashing/cutting action. Compare/contrast to mill chipper, tub grinder, and whole tree chipper.

hammer wedge --- Today's hammers are often made from single piece of steel with a a rubber handle around the tang, but early versions were made (and some are today as well) with wooden handles around a steel head, and this form requires a wedge to be driven into a slot in the top of the handle where it enters the head, to create expansive pressure that keeps the head from coming off of the handle. Some forms use two wedges, and some use a wooden wedge crossed by a steel wedge, but the fundamental form is a single steel wedge driven parallel to the long dimension of the head. Examples:



hand countersink --- A manual tool that allows you to drill out the upper portion of a hole so that the head of a screw will sit flush with the face of the object it is put into. There is a version that is used in drills just called the countersink bit. Examples:



handedness --- Various items in woodworking, including tools, locks, closers, some hinges and other hardware, require that you take into account a direction of motion and/or a method of mounting to accomdate that motion. The most widely known handed too is the scissors. It's very annoying to use a "normal" pair of scissors in your left hand so left-handed scissors were developed. For hinges, see hinge handedness.

hand held drum sander --- A drum sander in which the drum is somewhat like that used in a drill press drum sander except that it has a smooth shank on one end (like that for a drill press) but the other end, instead of just having a tightening nut, it has a handle that has a bearing that allows it to rotate. So you stick the shank into a hand held power drill or a flexible shaft tool, and hold onto the other end with your other hand and you have a rotating cylinder of sandpaper with which to smooth edges and things. The drums tend to be rigid but I believe I have seen models with a flexible pneumatic drum (see pneumatic drum sander). Compare/contrast to other forms of power sander. Examples:



hand plane --- A widely used hand tool, often just called a "plane" and sometimes a "bench plane", for shaping wood for cabinetry. In its simplest form, it is a block of wood with a cutting edge of steel projecting just below the surface of the bottom (the "sole") and when pushed over a wooden surface, it removes a slice off the top of that surface. The placement, angle, and shape of the blade can vary enormously with the particular type of plane (based on function). Mastery of the hand plane is one of the fundamentals of cabinetry. Beyond the basic form, there are versions that cut various types of grooves for use in joints, many of which are now much more easily made with a router. Also there is a powered version, the power plane which is a hand-held, but powered, version of the hand plane and then there is a floor model tool that does whole planks all at one time, called the planer. STILL TO COME: need to add some of the basic types of hand plane.

handrail --- a long, narrow strip or cylinder of wood used for grasping by hand, as an assistance to maintaining balance and/or help in climbing up a slope. A banister is one type of handrail.

handsaw --- In the USA, this is the standard manual saw for cutting planks. It is a flat sheet of steel with a wooden handle, shaped more or less as in the samples pictured below, and with the cutting edge serrated into sharp teeth or chisel-like sections. There are two fundamental cutting types, cross cut to cut across wood grain and rip to cut along the grain. In Europe, the bow saw is the more common manual saw type. Examples:



handscrew --- A traditional woodworking clamp with two long wooden jaws joined by two threaded rods that have handles in line with the shank. The rods adjust independently by turning the handles, which allows you to position the jaws parallel or at angles to one another. Handscrews come in a variety of sizes, based on the length of the jaws, generally from about 4" to as much as 12". There are two disadvantages of a handscrews. First, there's no quick release; the only way to move the jaws is by the slow turning of the screws, and second, it is hard to tell when the surfaces are really parallel to the workpiece (and thus providing even pressure). Examples:



hand sealing --- Very careful manual application of sealing compound for shingles on very steep slopes, in high wind areas, and when installing in cold weather.

hanger bolt --- A metal cylinder (not tapered and most commonly steel) with screw threads on one end and machine threads on the other end and the center either fully threaded or ,more often, "plain" which means there is a section without threading to make installation easier (you can grip the unthreaded part with vise grips). Often used with corner braces on the underside of table corners, where the screw threaded end is screwed into the table leg and the machine screw end runs through an angle bracket and which can then be tightened by the bolt on the that end of the hanger bolt. Another use is in overhead installation of things that need a machine screw to attach to but have to go into a wooden joist. Do not confuse with dowel screw which seems somewhat similar but has screw threads on both ends and has completely different uses. Vendors sometimes list these two different items indiscriminately as one being the other. Examples:



hanging stile --- The doorframe stile to which the door hinges are affixed.

hardboard --- A type of manufactured particle board made from ground wood pulp and resins pressed into sheets with a very smooth surface. A common brand of hardboard is Masonite which is readily available in most hardware store in panel sizes (4 feet by 8 feet). It also comes with a pre-drilled grid of holes and in a form commonly used to mount shop tools by way of hooked holders and in this form it is called pegboard. The best-known brand of hardboard is Masonite. Screws for use in hardboard often use hi lo threads.

hardness --- [same discussion given with toughness] Hardness and toughness are terms that have many, sometimes conflicting, characteristics depending on what definition you read, so take what I have here with a small grain of salt. Hardness is primarily the ability to resist deformation due to pressure. A hard surface is little affected by a sharp blow with a hammer but may be seriously scratched if rubbed by sandpaper. Some steels are good examples of this combination of characteristics. Toughness is primarily the ability to resist surface abrasion, so you could have a material that can be fairly easily deformed by pressure (and may or may not spring back to the non-deformed shape) yet which totally resists scratching. Some plastics have this combination of characteristics. In wood, toughness and hardness are fairly strongly related so it would be unusual to find a wood that is one but not the other. Durability in wood is primarily a function of toughness, but since hardness and toughness are strongly related in wood, harder woods tend to be more tough and thus more durable (in the mechanical sense; decay resistance is a separate issue). For wood, hardness is measured by the Janka scale; I am not aware of any scale for toughness in wood. Toughness also means the ability to withstand repeated blows or flexes without breaking. Leather, for example, is often quite tough but not hard at all.

hardwood --- A general term for timber of trees classified botanically as angiosperms. These are trees with broad leaves that the tree sheds each fall, and is to be contrasted with the softwood trees, which are conifers. NOTE There are exceptions to this discussion of leaves as regards hard/softwood, and these are discussed with the terms angiosperm and gymnosperm. Another sometimes misunderstood fact is that the term HARDwood has no reference to the relative hardness of the wood for any specific wood; the softest wood in the world (balsa) is a hardwood, and some softwoods are harder than some hardwoods. The name DOES derive from the fact that on average, a hardwood will be harder than a softwood, and in fact most hardwoods are harder than most softwoods but you can't count on it just based on the classification as a hard/softwood.

Hardwoods have traditionally been used in making such products as furniture, strip flooring, interior trim, cutting boards, novelties, and so forth, as opposed to general construction, which is performed with softwoods. Wood used in making these products is typically in the form of relatively small and defect-free pieces which are subsequently glued together. Hardwood is also generally more costly than wood from softwood species. Because of these factors, hardwood lumber is manufactured to non-standardized length and width dimensions which will minimize trim waste and such lumber is measured relatively accurately, with rounding of measurements in small increments. This is contrasted with softwoods, which are usually cut as dimension lumber.

hardwood dimension lumber --- Unlike dimension lumber which specifically indicates softwood lumber precut to a standard set of dimensions, this term refers to hardwood lumber processed to a user-specified thickness, width, and length.

harmonic chatter --- When what amounts to being chatter work occurs by accident, it is just called harmonic chatter, although that term is also sometimes used for deliberate chatter work.

hatchet --- A type of short axe used for chopping wood; the hatchet has a much shorter handle and a lighter head than an axe. Typically the size of a hatchet is about the same as a hammer. There are many styles available, with different length and style handles and grips and different shaped blades, with some having a straight cutting edge and some having a curved cutting edge. The back side of the head may or may not be suitable for use as a maul. Examples:



haunch --- An extra piece added to a tenon to give additional support against twisting forces. The haunch is normally added above the tenon but there's no rule saying it can't be added below the tenon if that's what makes sense structurally. See haunched mortise and tenon for an illustration.

haunched --- Has a haunch.

haunched mortise and tenon --- Sometimes, tenons that are not too big are in danger of pulling out if there is excessive twisting force applied to the piece of wood of which they are an extension. One way of alleviating this problem is to add a section that projects out above (or below) the tenon and also fits into a mating slot in the same piece that the tenon fits into; this extra piece, called a haunch, greatly increases the ability of the joint to withstand twisting forces. When such an extension is added the tenon is called a "haunched tenon" and the joint is called a haunched mortise and tenon. The haunch can be rectangular or sloped (see sloped haunch mortise and tenon) and if it goes all the way to the top of the piece the mortise is in, then it is an "open" haunch (see bridle joint). Examples of some tenons for haunched mortise and tenon joints:



haunched tenon --- see haunched mortise and tenon

HDO --- High Density Overlay

head --- (1) The top portion of a nail, screw, bolt, and many other items. The design of the head often distinguishes between and among such items and is specific to particular uses and tools.
head --- (2) The area at the top of a window or door in a building. See also header.

headboard --- A construction at the end of a bed (the end where your head goes); such constructions may or may not have elaborate designs and/or built-in cabinetry.

head bolt --- A bolt that is to be screwed into a threaded piece of metal, as opposed to being put THROUGH a piece and fastened on the other side with a nut. A head bolt in practice is identical to other bolts; the name is based on the USE, not the design. The head bolt IS likely to be threaded all the way up the shank whereas some bolts have an unthreaded section near the head.

header --- A horizontal framing member over a window or door opening. Often the header is a double thickness of "2x" lumber (2x6 or 2x8 or 2x10) sandwiching a 1/2" sheet of plywood to fill out the 3 1/2" depth of the studs. Headers are there to provide extra strength because the studs over the door or window, going up to the top plate are cripple studs instead of kingstuds. Example:



heading --- As regards woodworking, this refers to the lumber from which keg or barrel heads are made. Compare/contrast to barrel stave.

head jamb --- Depending on the exact construction technique used at the top of a door, this term can be either of two different constructs. First, it may be synonymous with header. Second, it can also refer to a 2x (usually 2x6) mounted with the wide dimension horizontal, at the top of a door frame, in which case the header is often just another single 2x also mounted with the wide dimension horizontal and placed above the head jamb with spacing blocks between them. The thicknesses of the spacing blocks can be adjusted if needed to make the head jamb be perfectly level. Example:



head lean --- A logging term referring to one of the two natural leaning forces found in most trees, the other being side lean; head lean is the greater of the two. It is the most prominent lean of a tree away from its base. See also back lean.

head rig --- [also headrig] The principle saw in a sawmill on which logs are first cut into cants. Depending on the type of mill, this might be a circular saw or a band saw. Generally, the term head rig includes the mechanism that moves the log into the main saw.

headside --- The piece of wood in a joint through which a screw or nail passes on its way into the receiving piece, which is known as the pointside.

headstock --- On a lathe, this is the part that holds the material to be turned (or hold it on one end in the case of spindle turnings) and attaches to a motor that powers the rotation. The headstock may incorporate the motor directly but more often the motor is below or to the side and attaches to the headstock arbor via a V belt. Illustrated with wood lathe.

headstock spindle --- The rotating center in the headstock of a lathe. The spindle is encased in bearings that allow it to turn freely. It is threaded on the outside to accept a faceplate or a chuck and has a hollow, tapered, inside that accepts fittings such as a spur drive. Illustrated at wood lathe

heart --- The very center of a tree, where the pith is. The wood called heartwood extends from the heart out to where the sapwood starts.

heart face --- The face grain surface of a plank that is all heartwood (that is, that face contains no sapwood, although the other side of the plank might).

heart shake --- A form of shake in which the wood develops cracks that radiate out from the center of the tree. Synonymous with star shake. Example in white mulberry:



heartwood --- The central, woody core of a tree consisting of inactive tissue that has support as its only function. It no longer carries sap up the tree and instead of water or reserved nutrients, heartwood cells contain substances such as resins, tannic acid, dyes, oils, rubber, or other organic compounds that provide commercial use to the timber and chemical industries and which also make the heartwood more durable and less susceptible to biodegrade than the sapwood. As a tree ages, the heartwood increases in diameter and becomes denser / harder and darker in color while the sapwood remains about the same thickness and color at the outer shell of the tree. Typically, some conifers such as spruce and pine and some flowering trees such as willows and poplars, do not contain heartwood and there are some species where the two both exist but are very similar to each other and hard to distinguish. In some trees the boundary between heartwood and sapwood is razor-sharp and in others it can be quite vague. See the term demarcation for examples. In many species it is only the heartwood that is valuable / usable, and the sapwood is discarded in woodworking.

heat gun --- A device very similar to an electric hair dryer; used to blow hot air over paint to soften it for removing, melt plastic for shaping, cause shrink-tubing to shrink, etc. They sometimes come with different shaped nozzles to direct the flow of air in particular ways. The one in the center of the composite image below is an old style, but I give it prominence of place because it is what I personally think of as a heat gun, since it is the style I was introduced to in the 1960's.



heat gun nozzle --- a shaped metal tube used at the end of a heat gun to direct the flow of hot air over a particularly shaped surface. For example, nozzles used to shink shrink-tubing often have a half-cylinder at the end to flow the air around all sides of the tubing, and nozzles used in paint removal often have a wide, narrow opening to flow the hot air over a large surface area without concentrating it at one small spot. Examples:



heat shield --- a noncombustible protector used around appliances, smoke pipes or chimneys to protect combustibles from heat sources.

heat treated lumber --- An ASLS term that means lumber that has been heated in a closed chamber, with or without moisture content reduction, until it has had a minimum core temperature of 56 degrees Celcius for a minimum of 30 minutes.

heavy timber --- In standard English usage this just has the obvious meaning of timber that weighs a lot, but there is a specialized meaning where the phrase refers to a particular type of construction with a good ability to resist the spread of fire in the structure.

heel cut --- The vertical cut in a bird's mouth joint (rafter notch). NOTE: I have found definitions that use the term "heel cut" as being synonymous with "bird's mouth notch", but I believe that this is incorrect. I have also found definitions that say that the heel cut is synonymous with "seat cut" but I am REALLY sure that this is not correct. Compare/contrast to seat cut. Example:



helve --- synonymous with haft --- I think this term is obsolete or at least obsolescent.

hemi-cellulose --- Cross-linked cellulose (somewhat more complex chemically than cellulose) that adds structural strength to the cellulose. Wood is nominally about 50% cellulose, 20% hemi-cellulose, 25% lignin (glue that holds it all together, and gives it compressive strength), and 5% "other stuff" such as gum, resin, sand-like crystals, and extractives (the chemicals that cause the difference between heartwood and sapwood).

herbaceous vegetation --- Low growing, non-woody plants, in a the understory portion of a forest.

herringbone --- A pattern produced by matching straight grained boards or veneer sheets so that their grain lines form the pattern shown in the sample figure below. This is a pattern widely used in cloth and brickwork and the name comes from the pattern of the bones of the herring (a fish) where they join the backbone. I have seen this incorrectly used in the phrase "herringbone figure" with wood. It is not possible that wood figure could result in a herringbone pattern (in a single piece of wood), it is only achievable by joining separate pieces of wood, and thus it is not a "figure" but a pattern. Below is a composite pic showing the classic herringbone pattern done in brick and then some examples of the pattern in wood flooring:



hewn timber --- Timber with or without wane, finished to size with hand tools such as an axe or adze.

hexagonal --- (commonly abbreviated as "hex") Having 6 sides. although it is not inherent in the definition of the term, it is normally assumed that the term refers to something with 6 sides of equal length.

hexagon hinge --- Supposedly, this is a type of butt hinge used with a cabinet that is set at a 45 degree angle in a corner, which makes the door and the two areas to each side of it three parts of a hexagon, thus the name. The panels of the door are beveled on the backside to 135 degrees and this hinge is designed to work with that. These types of doors are common in kitchens. NOTE: I have seen VERY few references to this type of hinge, I found one pic of it and forgot to save it and could not find it again (it was a butt hinge with an angle in one leaf) and I am doubtful about the need for this type of hinge since for the intended application, depending on the desired mounting technique and the specifics of the door/cabinet arrangement, one could use a simple butt hinge or a half cranked hinge or a full wrap around hinge or a partial wrap around hinge.

hex cap screw --- A cap screw with a hexagonal head

hex coupling nut --- see coupling nut

hex head bolt --- A bolt with a 6-sided head that can be easily turned with a crescent wrench. Such bolts may be threaded all the way along the shank or not. Examples:



hex head nut --- (also "hex nut") A machine nut with a hexagonal-shaped outer rim.

HF --- Hollow Form

H hinge --- Basically, a butt hinge with an "H" shape for use on inset doors. Although some versions could be edge mounted hinges, that does not seem to be at all the norm and most of them are face mounted hinges. Some are specifically designed for use on doors that are a bit thin for edge-mounted butt hinges. In any case, the "H" shape means the (hinge) leaves are taller than the (hinge) barrel which is a bit like on a parlimenthinge but more extreme. The short barrel is OK because this type of hinge is designed for only modest load-bearing requirements and the long leaves are both for decorative effect and to provide a longer surface in which to put mounting holes. Some that are use mostly for decorative purposes have mounting hole only at the top and bottom of each leaf. Small H hinges tend to be used for cabinet hinges, while larger ones are for passage doors or closet doors. A very similar hinge is the HL hinge. Examples:



hidden hinge --- synonymous with fully concealed hinge

hide glue --- A glue made from boiling animal (usually cow or horse) connective tissue. Horses that are put down are often said to have been "sent to the glue factory". This glue is applied hot and one of its primary characteristics, which can be an advantage or a disadvantage, is that it is water soluble. A place where it is an advantage is that glued joints can be un-glued later if desired. Musical instruments are sometimes made with hide glue for ease of repair. Hide glue has been in use for thousands of years. Bottled hide glue is available, but purists use a dry form that has to be mixed and boiled. The mixing and cooking and use of hide glue is a very involved topic and more than I want to get into here, so suffice it to say that there are numerous articles on the internet that will tell you more than you probably want to know.

hiding power --- The ability of paint or other finishing agent to mask the surface over which it has been applied. Hiding power is provided by a paint’s pigment (quality pigments cost more and work better), and is affected by how thickly the paint is applied and how many coats are applied.

high build --- A term referring to a finishingagent for which each coat produces a thick layer.

high collar lock washer --- An extra high split ring lock washer. Split ring lock washers are essentially just normal flat washers with a split in them but the high collar version isn't flat at all. Rather, it is more of a high cylinder than a flat cylinder. This makes it a much stronger locking mechanism than a normal split ring lock washer. Examples:



high density overlay --- [HDO] Exterior type plywood finished with a resin impregnated fiber overlay to provide extremely smooth hard surfaces that need no additional finishing and have high resistance to chemicals and abrasion. Some of the uses of HDO are concrete forms, highway signs, countertops, and other applications where strength and/or durability are needed.

high gloss --- see finish rating

high relief --- see relief carving

high speed steel --- [HSS] High speed steel; a grade of steel about 6 times harder than carbon steel and able to retain a cutting edge 5 to 10 times longer than carbon steel. HSS tools should be ground on a 'white' (aluminum oxide) grinding wheel.

hi lo thread --- A type of screw thread where there are actually two courses of thread, one higher than the other. These offer low driving torque and fairly high holding power in material that is somewhat curmbly such as masonry, wallboard, particle board, hardboard, etc. It is also fairly effective in very soft woods. The design traps material between the higher threads without causing it to crumble. Examples:



hinge --- Usually a three-part mechanism, normally but not necessarily made of metal, that holds two pieces of wood (or other material) together in a way that allows them to rotate, to a limited degree, relative to each other, around the axis of the hinge. The parts of the common types of hinges are the (hinge) pin and two (hinge) leaves but there are more types of hinges than you can shake a stick at and not every one of them is of the basic (butt hinge) type or even a variation on it. They are most commonly used for doors but have other uses (e.g. ships rudders, drop leaf tables). Types of hinges, and hinge-related terms, include: NOTE: INCOMPLETE SECTION --- some of the terms below are not yet defined and there are others not yet listed. Please note that some of the "definitions" given here are overly simplistic for brevity and the full definitions should be examined for a full understanding of the term. Also, while this list is reasonably comprehensive, it is not exhaustive. There are some hinge types that are so rarely seen/used that little information is available on them and it is also possible that some of them are only available from one manufacturer. I figure that if they are that obscure, I don't really need to have them here. An example of this is the "pivot reinforced (butt) hinge".

hinge barrel --- The portion of the (hinge) leaves that contains the (hinge) knuckles that accept the (hinge) pin. When talking about this item in relation to hinges, it is never called the "hinge barrel", it is just called the "barrel". For an illustration, see hinge parts.

hinge cup --- part of a European hinge

hinge dimensions --- The graphic below describes the various dimensions that apply to "standard" hinges such as the butt hinge (but not to some other types such as the European hinge).

need to add hinge dimensions pics


hinge finial --- A finial that is put on the top or bottom of a hinge pin to give the hinge a more decorative appearance. Examples:

need to add hinge finialpics


hinge handedness --- add definition

hinge jamb --- The door jamb on the side where the door hinge is mounted. Compare/contrast to strike jamb.

hinge knuckle --- The parts of a hinge that make up the (hinge) barrel through which the (hinge) pin goes. For an illustrations, see hinge parts and hinge dimensions.

hinge leaf --- the flat part of a hinge that attaches to a frame or the object being hinged. When talking about this item in relation to hinges, it is never called the "hinge leaf", it is just called the "leaf", although sometimes the one that attaches to a door is called the "door leaf" and the one that attaches to a frame is called the "frame leaf". For an illustration, see hinge parts.

hinge length --- The length of the leaves of a hinge parallel to the pin. See hinge dimensions.

hinge mounting positions and styles --- A graphic showing various ways that hinges can be mounted on the edge and face of a door or frame, with and without mortises.



hinge parts --- A simple illustration of the (hinge) barrel, the (hinge) leaf, the (hinge) knuckle, and the (hinge) pin sections of a common style hinge. I put "(hinge)" in front of these terms because technically, that's the right name, but it is overly formal and not normally used in the context of talking about a hinge. Sometimes, depending on what is being hinged and how it is being hinged, the two leaves may be referred to as the door leaf and the frame leaf (for example, this would apply when hanging a house door. The knuckles of the two leaves mate up to form a hollow cylinder called the barrel, into which is slipped the pin. This is the simple, or "standard" hinge style, but there are many others, some of which do not look anything like this. The illustration shown below is a butt hinge but it is illustrative in general of many styles.



hinge pin --- the solid cylinder central part of a hinge that slips into the (hinge) knuckles to keep the two (hinge) leaves from separating. When talking about this item in relation to hinges, it is rarely called the "hinge pin", it is normally just called the "pin". For an illustration, see hinge parts.

hinge pitch --- On a hinge, this is the length from one point on a knuckle to the same point on the next knuckle up, taken parallel to the (hinge) barrel. See hinge dimensions. It is interesting to note that even if the knuckles on the leaves are different heights, the pitch will be the same on both leaves (assuming there is not an unusual amount of end play due to one set of knuckles being shorter than the opening left by the other set).

hinge stile --- A door stile to which a hinge is affixed.

hinge width --- The distance from the outer edge of one leaf to the outer edge of the other leaf when the hinge is lying flat. See hinge dimensions.

hip --- The line where two roof planes meet.

hip leg --- One of The downward angled ridges on hip roofs. See hip roof for illustration.

hip roof --- A gable roof but with the top ends sliced off at an angle and covered with another roof plane, so that the roof has four roof planes and four separate hip legs. Example:



hit and miss --- When a planing operation on a plank results in only some of a plank's surface being planed and some of it having skip, that is called hit and miss skip. Compare/contrast to hit or miss.

hit or miss --- Refers to lumber that may have been planed or may have be rough sawn but which in either case has a surface depth variation of no more than 1/16th of an inch. Compare/contrast to hit and miss.

HL hinge --- Similar to an H hinge except that there is a long horizontal tab on one leaf which means it HAS to be face mounted rather than edge mounted. Large HL hinges were common for passage doors, room doors and closet doors in the 17th, 18th and even 19th centuries. On taller doors H hinges were occasionally used in the middle along with HL hinges at the top and bottom. I noticed that every example I found of this type hinge had plain bore screw holes, never countersunk. I hypothesize that this is because back when these were in common use, cleanly countersinking the screw holes was not as trivial as it is today and countersunk screws were likely not as readily available. Since these are used at both the top and the bottom of a door there is a handedness to them. They are always positioned so that the top hinge has the long leaf portion at the top and the bottom one has it at the bottom. Examples:



hobnail --- a short nail with a thick head used to protect the soles of some boots. I have seen another definition saying that the term refers to pattern of pin-holes left by insect attack but I have seen that definition in only one place and have no confidence in it.

hog --- see hogging

hogging --- Removing a large amount of wood. There is an implication that this is done in an inelegant way as a rough early step towards reducing a workpiece to its final shape, and the term is mostly used in woodturning and woodcarving.

hold down clamp --- A type of bench clamp; it fits into a hole in the top of the bench, is shaped somewhat like and upside down letter "L", and is tightened by tapping it down with a hammer, and it is loosened by tapping the side with a hammer. It is also called a bench holdfast. It uses the bench top as one of the clamping jaws. Toggle clamps are also sometimes referred to as hold down clamps. Examples:



holdfast --- synonymous with holddown clamp

hold fast --- synonymous with hold down clamp

holding wood --- In felling trees, this is a section of wood located between the face and the felling cut. It is also called the stump shot. Its purpose is to prevent the tree from separating from the stump until it is falling towards the face. It also helps direct where the tree will fall. The holding wood must never be completely sawn off but rather in proper felling it breaks off as the tree falls over.

hole punch --- see leather punch (the office-supply tool for punching holes in paper is not a woodworking tool and is not considered here)

hole saw --- A metallic cylinder with saw teeth on one rim and with the other end curving over into a plate with a usually hexagonal cutout that fits into a special arbor. The arbor generally contains a twist drill bit and the whole thing is used for cutting out holes, usually in fairly thin material. Some are very heavy duty with carbide cutting edges and some are sold in very cheap sets of simple metal cylinders that fit into a multi-holder. They are used with a power drills, stationary or hand held. Examples:



holiday --- A finishing term referring to any bare or thin spot (you missed a spot!).

hollow core --- a type of door or panel that is made by adhering outer plys of wood veneer sheets to a wooden frame but leaving the inner part empty except for the frame. Such doors are lightweight, inexpensive, and can be readily identified by simply knocking on them to detect the hollow sound and feel. They are commonly used for interior doors in low-end residences.Compare/contrast to solid core.

hollow form --- A term wood turners use to describe a turned container that has only a small opening through which the turning tools can be inserted while the turning the inside. It is difficult to turn such items, and particularly difficult to get the wall thickness consistent, because the turner is working blind. There are elaborate (and sometimes expensive) mechanical contraptions (see captive hollowing tool) that assist in the turning of the inside of such items. The term "hollow form" is somewhat vague and you might see identical forms referred to by one turner as a hollow form and by another as a vessel, a vase, or an urn. I have attempted to clarify the distinctions with a description of the various lathe turnings. Examples:



hollow grind --- synonymous with hollow ground

hollow ground --- (1) A concave bevel on the cutting edge of a knife, chisel or other edged tool. Compare/contrast to flat grind.
hollow ground --- (2) When referring to circular saw blades, this means that they are reduced in thickness from the rim in toward their centers, usually only for an inch or two. This is most commonly done on veneer blades because some veneer is so fragile that the pressure from the flat edge of the saw blade can cause splintering at the edge of a cut as the flat edge rises up into the edge that has already been cut by the teeth as the teeth move further along the surface of the veneer.

Example of knife blade:



hollowing tool --- A lathe tool; this is a somewhat generic name for any number of different lathe tools that all have the same purpose, namely that of hollowing out the inside of a turned vessel (e.g. a vase). There are versions that have replaceable tips and numerous differently shaped solid tip versions. When the shank has a bend in it to facilitate reaching behind the inside of the lip of the vessel, the tool is sometimes called a swan neck hollowing tool. For very elaborate versions with articulated arms, see captive hollowing tool. Here are some examples:



hone --- [noun] A sharpening stone with a very fine grit, used to put the final touch on a sharp edge, or to remove very fine burrs from such an edge.
hone --- [verb] To make the final step in sharpening a knife or chisel or other thin cutting edge, by rubbing it repeatedly at a sharp angle against a very fine grit stone or a leather strop. This removes any burr created in the grinding and brings the blade to a final degree of sharpness. See also grind / hone / polish.

honed --- see hone (verb form)

honeycomb --- Internal splitting or collapse, often not visible at the wood surface, that develops as a drying defect. It is caused by internal stresses or by the closing of surface checks during drying. In extreme form, it can produce an internal structure, seen when crosscutting a plank, that somewhat resembles an actual honeycomb (the geometric hexagonal kind made by made by honeybees) and it is sometimes evidenced by a surface depression (in the case of collapse) on the face of a plank.

honing --- see hone [verb]

hook --- A metal rod, threaded on one end and bent on the other end into a shape that depends on the use. Common types:

hook and eye --- synonymous with gate hook

hook gate --- synonymous with sizing tool

horizontal face cut --- The first of the two cuts of a facing cut when felling a tree. This is, as the name implies, a horizontal cut, and its depth is at least 1/3 the diameter of the tree.

horizontally laminated timber --- Laminated timber designed to resist bending loads applied perpendicular to the wide face of the laminations. For vertical loads, this means that the wide face runs horizontally.

horizontally wedged mortise and tenon --- This is a tusked mortise and tenon but with the wedge going sideways instead of up and down, due to the grain orientation of the piece that accepts the wedge. Wedges should always be placed such that they exert force in a longitudinal direction relative to the grain of the piece of wood accepting them, otherwise they may well cause a split in that piece. Note that the cutout for the wedge is angled at the outer edge at the same angle as the angle on the wedge, so that the wedge force is distributed evenly. Note also that the inner edge of the cutout is recessed from the face that the wedge pressure is on because otherwise the wedge would not exert any pulling force on the piece that is receiving it. Examples:



horizontal shear --- The measure of the resistance of the shearing stress along the longitudinal axis of a piece of wood. For example, when a load is applied in the middle of a plank that is supported at each end, the plank tends to bend downward in the middle and there is a stress over each support that tends to slide the fibers across each other horizontally inside the plank. The internal force that resists this action is the horizontal shear strength of the wood.

horn --- waste wood left on a workpiece to support the end of a mortise or spindle turning while it is being cut or turned. The horn acts as a support while the piece is being cut or turned and possibly also while it is being put into use, but which is ultimately removed from the final piece by cutting/sanding. I have also seen the term used to describe extended door or window stiles designed to protect the corners from being damaged prior to final use.

horned dado --- On a stacked head dado cutter for a circular saw, the outside blades on some sets cut just a little deeper than the inside blades (the chippers) and this results in what can, with a great deal of imagination, be looked at as a flat-topped head with little bitty horns sticking up at the sides, thus it is called a horned dado cut. Here is a greatly exaggerated example, to show it clearly:



horsepower --- [also HP] A measurement of power, nominally equal to the pulling strength of one horse, or more technically, the power needed to lift 550 pounds one foot off the ground in one second. Horsepower is rarely used in scientific measurements of power but is widely used for cars and tools. One horsepower is equivalent to 746 Watts which means that a 110 volt house circuit has to deliver 6.7 amps to provide one HP and a 15 amp circuit breaker will trip at 2.2HP so if you have a 3 HP motor in one of your tools, you can't use a standard house line with the standard 15 amp breaker. Common shop tools use anything from a small fraction of one HP for a small hand-held tool, up to several HP for stationary tools.

hospital tip hinge --- A butt hinge with a (hinge) barrel that is beveled on both the top and the bottom towards the door when the door is closed. This is for use in detention centers and hospitals and is to prevent the barrel from being used to hang things (most particularly self-hanging of suicidal people). Examples:

need to add hospital tip hinge pics


housed joint --- A joint where one piece is notched or grooved to receive the other piece, such as in a dado joint. The groove is called the "housing" and the ungrooved piece is said to be "housed" in the groove, thus the name. The groove can be through, blind, or half blind and the joint is still called a housed joint.

housed mortise and tenon --- A mortise and tenon joint in which the piece that has the mortise also has a slight recess into which the piece with the tenon fits. This provides considerable extra support in two directions, and is normally done to provide extra strength in the downward direction (hey, we all have to fight gravity). Examples:



housing --- (1) The external, protective casing shell of a machine.
housing --- (2) A groove, such as a dado, that accepts a shelf, stair tread, dovetail, etc. See housed joint.

HP --- An abbreviation for horsepower

HSS --- High Speed Steel

hue --- see color terms

humidity --- see relative humidity

hung sash window --- synonymous with sash window, although it is apparently sometimes used to mean that only one of the sashes has a sash weight instead of both of them.

hung tree --- A tree leaning against another tree or object which prevents it from falling over to the ground when cut off at the base.

HVLP --- High Volume Low Pressure (a type of spray-gun mechanism). See also LVLP.

hybrid table saw --- A somewhat ill-defined term, but basically it describes a contractor saw but with the motor inside an enclosure (like a cabinet saw) instead of hanging out the back. Moving the motor inside a steel housing offers several advantages over the contractor saw including smaller footprint, improved dust collection, more mass, no lifting hazard when tilting the blade, and the shorter drive belt has less vibration and more efficient power transfer. This is a good option if you want a bit more saw than a contractor saw but aren't ready for the large footprint and hefty price of a cabinet saw. A hybrid saw can generally support larger fences than a contractor saw. The hybrid saw does NOT move the trunnion mount from the table (where it is on a contractor saw) to the cabinet (where it is on a cabinet saw, which is better for several reasons) and the motor is still in line with the blade's arbor as in a contractor saw. Compare/contrast to cabinet saw, contractor saw and bench top table saw. Examples:



hydrocarbon --- Extracts from petroleum; includes such common items as gasoline, lubricating oils, solvents, etc.

hydrophilic --- A substance which absorbs, or has an affinity for, water.

hydrophobic --- A substance which neither absorbs, nor exhibits an affinity for, water.

hygrometer --- An instrument for measuring the relative humidity of air.

hygroscopic --- The characteristic of being able to both absorb and release moisture with changes in the surrounding atmosphere. Wood is hygroscopic and tends to swell when it absorbs moisture and shrink when it gives off moisture. This results in movement in service which can be a serious problem if not accounted for with such things as rail and stile construction.

hyperbolic paraboloid --- a complex 3D conic form which has the very useful attribute that there is one place where the apparently always-curved surface contains a straight line and if you rotate the hyperbolic paraboloid around its axis the place where the line is stays right there. This means that you can nest two of these things made of metal in a particular way with their "line places" together (this requires skewing the axis of one to the other) and rotate both of them in synchronization (but opposite directions) and what you then have is a pair of rotating surfaces that exactly contain a straight cylindrical object such as a broom-handle. Such devices are used to create perfectly straight metal bars from otherwise bent stock. For example, heavy wire can be fed from a roll into such a device and what comes out is a straight bar which can then be cut off in lengths to make, for example, wire nails. Examples:



hypsometer --- Any of several tools or instruments, using different techniques but all designed to measure the height of trees. The clinometer is such a tool.


for images of wood itself, go here: wood id site
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