Halved pattern to Hardening

Halved pattern. (Patmkg.) A foundry pattern made in two parts to per­
mit withdrawal from the sand when molding. .
Halving. The making of a joint by cutting away half of the thickness from the face of one piece and the other half from the back of the piece to be fitted to it, so that when the two are put together the outer sur­faces will be flush.
Hammer. An instrument or tool used for striking blows in metalworking, driving, nails, etc. Hammers are of various kinds, each bearing a name according to the purpose it is to serve. The name is applied to ma­chines, such as are used in forging, as well as to hand "hammers."
Handbill. (Print.) A small printed ad­vertisement for distribution by hand. (See Dodger.)
Hand blocking. (Furn.) A process of dyeing a design in upholstery ma­terial.
Handbook. A book of reference to be carried in the hand. A manual or guide, usually containing a compi­lation of data and formulas, as an engineering handbook. and brake. (Auto.) A brake oper­ated by hand, used principally as a parking brake. When applied. it remains set until released by hand
HanddoUy. (Sheet-Met. Wk.)A5fed block, rectangular in section, and fitted with handle on the under­side. The usual size is about 5 by 6 in., with a thickness of I in. The working face is curved to fit Ibe inside -of fenders, tanks, etc. Par­ticularly useful as a support inside of tanks when seaming by h~Or for use as a stake. (See BoDy bloc:ks.)
Hand drill. (Shopwk.) A machine operated by hand.
Handed. (Meeh) When two similar pieces are to be used on to Ibe right and the other to the left. or are so attached to som other pari. they are said to be right-handc:dor left-handed. Workmen's tools are also so designated, depending OlD whether they are to be used with the left or the right hand.
Hand feed. The feeding by hand of the cutting tools of machines of various kinds.
Hand file. (Shopwk.) This filehaspar­allel sides but is tapered in thict­ness. It is double cut with various degrees offineness. Its principal use is in finishing flat surfaces.
Hand hook or hook wrench. (MedL) A long bar with a hook end to be used in straightening bent pieces. such as axles.
Handiwork. Work done by baad. . Usually refers to work which ~ quires some skill.
Hand-made finish. (Papermkg.) A term descriptive of the handmade appearance of certain papers. 11

Hand miller to Hardening does not mark them as being, in reality, handmade.
Hand miller. (Mach.) A small mill­ing machine with the feed oper­ated by hand. It is adapted only to light work.
Handrail. (Arch.) A rail, as on a stair or at the edge of a gallery, placed for convenient grasping by the hand.
Handrail wreath. (Arch. and Bldg.) Curved ser.tion of a stair rail.
Hand rule. (Elec.) If a conductor, car­rying current, is grasped in the right hand with the extended thumb point­ing in the direction of the flow of current, the fingers will indicate the direction of the resulting lines of force.
Handsaw. (Shopwk.)An ordinary one­handled saw, either rip or cross-cut. used by wood workers.
Hand screw. A woodworkers' clamp consisting of two par!lllel jaws and two screws. Clamping action is ob­tained by means of the screws, one operating through each jaw.
Hand tools. (Shopwk.) Tools that are guided and operated by hand.
Hand turning. (Shopwk.) Turning accomplished by tools held in the hand. .
Hand vise. (Shopwk.) A small vise held in the hand, used for clamp­ing small, light work.
Handwheel. (Mach.) Any wheel op­erated by hand, usually for adjust­ment. , Hangar. A building or structure for housing airplanes.
Hanger. (Arch.) A strap of iron or steel used as a drop support, at­tached to one beam or joist and used to support the end of another. (M ech.)A frame and bearing used in se­ries to support shafting from the floor, side wall, or overhead.
Hanger bearing. (Mach.) A shaft bearing supported by a hanger.
Hanger bolt. (Mach.) Consists of a lag screw at one end and a ma­chine-bolt thread and nut at the other. It is used for attaching hang­ers to woodwork.
Hanging core. (Fdry.) Core sup­ported by a wire hanger that is imbedded in the core. Hanging cores are used to avoid a deep lift for the core.
Hanging indention. (Print.) First line of a paragraph extending to the left of text.
Hanging stile. (Bldg.) That vertical part of a door or of a casement window to which the hinges are fastened.
Hard. (Ceram.) Material which can­ not be used or melted.
Hard brass. Brass which has not been annealed after drawing or rolling; used for springs, etc.
Hard-drawn copper wire. (Elec.) Copper, when drawn through sev­eral dies to size, becomes hard. This hard wire is used on tele­phone- and telegraph-pole lines where its greater tensile strength is desired.
Hardener (Pfast.) See Catalyst.
Hardening. Hardening of steel is brought about by heating it to a high temperature and then suddenly cooling it in oils, water, or other suitable solutions. Special steel may require differen methods of hardening.