JOINERY. 



f n fomc cafes, vrhtte a grtat number of pieces are required 

 to be wrought to the fame angle, a llationary bevel, called a 

 joint hook, is ufed. 



When it is required to reduce a piece of ftulF to a parallel 

 breadth, an inftrumeiit called a gage is ufcd for the purpofe. 

 The gage confills generally of a iqiiare piece with a fquare 

 mortifc, through which a bar at riglit angles thereto is Htted 

 and made to Hide. The bar, which is called the (Icm. lias 

 a (harp point, cutter, or tooth at one extremity, projecting a 

 little from the furface, fo that when the lidc of the gage, 

 next to the end which has the point, is applied upon the 

 vertical furface of tlie wood, with the flat tide of the ftem 

 which has the tooth upon the horizontal furface, and puftied 

 and drawn alternately by the workman from and towards 

 hira, the cutter will make an incilion from the furface into 

 the wood, at a parallel diftance from the upper edge of 

 the vertical fide on the right hand. This line, fo drawn, 

 will mark out with precifion, and (hew the fuperfluous (luff 

 to be taken away. 



When a mortife is required to be cut in a piece of wood, 



a gage with two teeth is ufed. The condruCtion of this 



inftrument is the fame as the common gage ; but in addition 



thereto, the ftcm has a longitudinal (lider with a tooth pro. 



jecting from the end of the Aider, fo that tlie two teeth 



, may be brought nearer, or to any remote diftance from 



4 each other, at pleafure ; and alfo to any diftance, from the 



j5 face of the head or guide within the reach of the ftem. 



^ When wood has been planed, and required to he fawn 



J. acrofs the fibres, and as it is necclTary to be kept ftationary 



j while fawing, in order to prevent the fides or the edges 



#/ from being bruifed, joiners ufe a flat piece of wood with 



two projeeting knobs on the oppofite fides, one at each end, 



called a fide hook. The vertical lide of the interior angle 



of one of the knobs is placed clofc to the vertical fide, and 



the under fide upon the top of the bench ; then the wood is 



prefTed againft the knob which projeifts from the upper 



furface while it is cutting with the faw ; but the ufe of 



two fide hooks is better, as they keep the piece of wood to 



be fawn more fteady. 



When it is required to cut a piece of wood to a mitre 

 with one (idi ; that is, to half a right angle, joiners ufe a 

 trunk of wood with three fides, like a box without ends, or 

 a top, the fides and bottom being parallel pieces, and the 

 fides of equal heights : through each of the oppofite fides 

 is cut a kerf in a plane, perpendicular to the bottom, at 

 oblique angles of 45 and 1 35 degrees, with the planes of the 

 fides ; and another kerf is made in the fame manjier, fo as 

 to have its plane at right angles to the former. The trunk 

 thus ccmttructed is called a mitre-liox. When the wood is 

 to be cut, the mitre-box is fixed (leady againft two fide 

 hooks, and the piece, which is always lefs than the interior 

 breadth of the mitre-box, is laid within, and prefTed againft 

 the farther interior angle of the mitre-box with the fide 

 downwards, to which the faw-kerf is intended to be per- 

 pendicular, and in this pofition it is to be cut. Tlie two 

 kerfs ill the fides of the mitre-box are requifite, in order to 

 form the acute angle on the right or left-hand fide of the 

 piece, as may be required. 



When it is required to make a piece of wood ftraight in 

 one direftion, joiners ufe a (lip of wood llraightened on one 

 edge, from which the flip of wood itfelf is called a (Iraight 

 ^dge. Its ufe is obvious ; by its application it will be 

 feen whether there is a coincidence between the ftraight edge 

 and the furface. 



When it is required to know whether the furface of a 

 piece of wood is in the fame plane, joiners ufe two flijis of 

 «-ood ftraiglitened each on one ed 'c with the oppofite edge 

 Vol XfX. 



parallel, and both pieces of the fame breadth between the 

 parallel edges : each piece has therefore two ftraight edges. 

 Stippofe it wore required to know whether a board it 

 twilled or its furface in a plane, tlie workman lays one of 

 the Hips acrofs the one end, and the other acrofs the other 

 end of the board, with one of the ftraight edges of each 

 upon the furface ; then he looks in the longitudinal dircttion 

 of the board, over the upper edges of tlic two flips, until his 

 eye and the two upper edges of the (lips arc in one plane ; 

 orotherwife, the interfeftion of the plane, p-ifGng through 

 the eye and the upper edge of the neareft flip, interfeft the 

 upper edge of the farther (lip. If it happen as in the f rn er 

 cafe, the ends of the wood under the (lips are in the fame 

 plane; but (hould it happen as in the latter, they are net. In 

 this laft cafe the furface is faid to wind ; and when the fur- 

 face is fo reduced that every two lines are in one plane, it 

 is faid to be out of winding, which implies its being an en- 

 tire plane : from the ufe of thcfe (lips they are denominated 

 winding flicks. 



Before we can proceed to the method of bringing a rough 

 furface to a plane, it will Grft be neceffary to (hew how to 

 make a ftraight edge or ruller. 



Here the joiner nuift not lofe fight of the definition of 

 a (Iraight line, viz.. a ftraight line is that which will always 

 coincide with another (Iraight line, however applied to- 

 gether. 



The operation of making the edge of a board ftraight is 

 called by joiners (hooting, and the edge fo made is faid to 

 be (hot. 



Straight edges may be thus formed ^ plane the edges of 

 two boards and apply them togetlier, fo that the fuperficie* 

 or faces of the boards be in the fame plane, and if there 

 be no cavity between the joint the edges will be ftraight ; 

 but it not, the faces mutt be applied to each other, the 

 edges brought together, and planed and tried as before, until 

 they are found to coincide. 



Another mode it by having a plane furface given ; plane 

 the edges of a board as llraight as the eye will admit of, 

 and apply the face of it to tiiat of the plane, and by the 

 edge of the board draw a line, turn the board over with 

 the other fide upon the plane, and bring the planed edge 

 to the line drawn before, and the extremities of the edg-« 

 to their former places, and draw another line ; then if all 

 the parts of this line coincide with the former line, the edge 

 it already (Iraight, but if not, repeat the operation at oftea 

 as may be found neceflary- 



Another mode is to plane the edge of a board as ftraight 

 as the eye will admit of; then plane the edge of another 

 board until it ii made to coincide with the former ; take a 

 third board and plane the edge of thii in like manner, by- 

 making it coincide with the edge of the firft board ; apply 

 the edges of the two lall boards together, tlieri if they 

 coincide the operation ii at an end, but if not, repeat it at 

 often as may be found nece(rary. 



By any of the methods now (hewn, the fuperficies of the 

 boards, to be fliot, are fuppofed to be parallel planes not 

 very- diftant from each other ; for if the faces be not parallel, 

 or if the thicknefs be confiderable, the operation wiU be the 

 more liable to error. 



To reduce the rough Jvrface (f a body to o plane. — TIii« 

 will not be very diflicult, when it is known that a plane it 

 that which will every where coincide with a ftraight line. 



The moft practical metliods are the following : Let the 

 workman provide two winding (licks, and apply them at 

 before dircdled, making the cods out of winding if they 

 are not found to be fo ; then if all the parts of the furfice 

 are ftraight on which the edges of the windiinj ^^'<^^' "■^'''' 

 V J- placed, 



