PlansNow - Dovetail Jig

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Plans N O W page 1 © 1999, August Home Publishing Co. Dovetail Jig MAGAZINE W oodsmith from hen I first started to build this dove- tail jig, I thought the advantage was going to be the low cost. Dovetail jigs are priced from $50 up, but you can make the one shown here for about $30. All you need is some standard off-the-shelf hardware, five board feet of hardwood, and a piece of 1 / 4" Masonite to make your own “comb” template. SOLVING DESIGN PROBLEMS As I worked on the design, I began to think about what I didn’t like about the dovetail jigs I’ve used before. The main problem I’ve had with other jigs is the system for holding the workpieces tight to the jig. (If the wood shifts even slightly, the joint won’t fit together correctly.) On most jigs the workpieces are held with metal bars. The bars are tightened down with wing nuts or knobs. But you just can’t tighten them enough to keep the wood from moving around as you rout. And, on some of the jigs, the metal bar bends as the wing nuts are tightened. CAMS. To solve these problems, the jig shown here uses cams. They’re much eas- ier on the fingers and work faster than wing nuts. And you can apply considerably more pressure down against the work- pieces. (We’ve cut well over 100 joints with this jig, and I haven’t seen a workpiece shift out of position yet.) It’s also easier to quickly change the pieces if you’re doing a number of joints. PRESSURE BARS. However, with all that pressure building up from the cams, you need strong bars that won’t bend. (I used 1 5 / 8"-thick hard maple to make the bars.) BASE The first step in making the jig is to build the base. It’s built up from three pieces of 4/4 hardwood ( 3 / 4" to 13 / 16" actual thickness). (Note: You could also use one piece of 8/4 stock and one piece of 4/4 stock.) It’s impor- tant to use a tight-grained hardwood such as maple so the threaded inserts won’t pull out. CUT AND GLUE BASE PIECES. I began by cutting two base top pieces (A) to rough dimensions of 6 1 / 2" wide and 19" long and laminating the pieces together face-to-face. After this blank is dry, cut it to a finished length of 18", see Fig. 1. Next, I cut a base bottom piece (B) from 4/4 stock to a rough width of 6 1 / 2" and fin- ished length of 22". Then screw and glue this piece onto the bottom of the top blank so there are 2" wings overhanging on each end. (The wings are used for clamping the jig down to a bench or table, see photo.) CUT TO WIDTH. Once the base is assem- bled, trim it down to a finished width of 6", see Fig. 1. When trimming the front edge, make sure it’s exactly 90° to the top. DRILL HOLES. After the base block was trimmed, I drilled six holes in it. First, drill two 1 / 8"-dia. pilot holes in the top, 1 / 2" from the front edge (see Fig. 1), to hold stop blocks that are added later (refer to Fig. 19 on page 4). The other four holes are for the 5 / 16" threaded inserts that will accept eye bolts for the cams, refer to Fig. 7. However, before drilling the holes for the inserts, I Shop-Made Jig for Cutting Half-Blind Dovetails W counterbored 9 / 16"-dia. holes 1 / 4" deep to make a space for the springs that hold the pressure bars away from the jig, see Detail in Fig. 1. After counterboring, I drilled a 1 / 2"-dia hole to accept the threaded insert. This hole has to be 2" deep so the eye bolt can be screwed all the way through the thread- ed insert, refer to Fig. 2. Shop Note: Most 5 / 16" (inside diameter) threaded inserts tighten into a 1 / 2"-dia. hole, but some require a smaller diameter hole. Drill the holes to match the specific inserts you have. MOUNT INSERTS. After the holes are drilled, tighten the inserts down so they’re set 1 / 4" below the surface, see Detail in Fig. 2. To do this I tightened two nuts against A B FIGURE 1 FIRST: GLUE TOP PIECES TOGETHER, THEN CUT TO FINISHED LENGTH %/16” I.D. THREADED INSERT SEE DETAIL SECOND: GLUE BOTTOM TO TOP PIECES BASE TOPS 18” 1” 2 !/2 2” 2” !/26” BASE BOTTOM ROUND ALL CORNERS THIRD: TRIM TO FINAL WIDTH 22” DETAIL FIRST DRILL COUNTERBORE (/16 SECOND, DRILL ” HOLE !/2 !/41 #/4 2” DRILL ” HOLES FOR STOP BLOCKS, ” DEEP !/8 #/8

Transcript of PlansNow - Dovetail Jig

Page 1: PlansNow - Dovetail Jig

Plans N O W page 1 © 1999, August Home Publishing Co.

Dovetail JigMAGAZINE

Woodsmithfrom

hen I first started to build this dove-tail jig, I thought the advantage was

going to be the low cost. Dovetail jigs arepriced from $50 up, but you can make theone shown here for about $30. All you needis some standard off-the-shelf hardware,five board feet of hardwood, and a piece of1/4" Masonite to make your own “comb”template.

SOLVING DESIGN PROBLEMSAs I worked on the design, I began to thinkabout what I didn’t like about the dovetailjigs I’ve used before. The main problemI’ve had with other jigs is the system forholding the workpieces tight to the jig. (Ifthe wood shifts even slightly, the joint won’tfit together correctly.)

On most jigs the workpieces are heldwith metal bars. The bars are tighteneddown with wing nuts or knobs. But youjust can’t tighten them enough to keep thewood from moving around as you rout. And,on some of the jigs, the metal bar bends asthe wing nuts are tightened.

CAMS. To solve these problems, the jigshown here uses cams. They’re much eas-ier on the fingers and work faster thanwing nuts. And you can apply considerablymore pressure down against the work-pieces. (We’ve cut well over 100 joints withthis jig, and I haven’t seen a workpieceshift out of position yet.) It’s also easier toquickly change the pieces if you’re doing anumber of joints.

PRESSURE BARS. However, with all thatpressure building up from the cams, youneed strong bars that won’t bend. (I used15/8"-thick hard maple to make the bars.)

BASEThe first step in making the jig is to buildthe base. It’s built up from three pieces of4/4 hardwood (3/4" to 13/16" actual thickness).(Note: You could also use one piece of 8/4stock and one piece of 4/4 stock.) It’s impor-tant to use a tight-grained hardwood suchas maple so the threaded inserts won’t pullout.

CUT AND GLUE BASE PIECES. I began bycutting two base top pieces (A) to roughdimensions of 61/2" wide and 19" long andlaminating the pieces together face-to-face.After this blank is dry, cut it to a finishedlength of 18", see Fig. 1.

Next, I cut a base bottom piece (B) from4/4 stock to a rough width of 61/2" and fin-ished length of 22". Then screw and glue

this piece onto the bottom of the top blankso there are 2" wings overhanging on eachend. (The wings are used for clamping thejig down to a bench or table, see photo.)

CUT TO WIDTH. Once the base is assem-bled, trim it down to a finished width of 6",see Fig. 1. When trimming the front edge,make sure it’s exactly 90° to the top.

DRILL HOLES. After the base block wastrimmed, I drilled six holes in it. First, drilltwo 1/8"-dia. pilot holes in the top, 1/2" fromthe front edge (see Fig. 1), to hold stopblocks that are added later (refer to Fig. 19on page 4).

The other four holes are for the 5/16"threaded inserts that will accept eye boltsfor the cams, refer to Fig. 7. However,before drilling the holes for the inserts, I

Shop-Made Jig for Cutting Half-Blind Dovetails

W

counterbored 9/16"-dia. holes 1/4" deep tomake a space for the springs that hold thepressure bars away from the jig, see Detailin Fig. 1.

After counterboring, I drilled a 1/2"-diahole to accept the threaded insert. Thishole has to be 2" deep so the eye bolt canbe screwed all the way through the thread-ed insert, refer to Fig. 2.

Shop Note: Most 5/16" (inside diameter)threaded inserts tighten into a 1/2"-dia. hole,but some require a smaller diameter hole.Drill the holes to match the specific insertsyou have.

MOUNT INSERTS. After the holes aredrilled, tighten the inserts down so they’reset 1/4" below the surface, see Detail in Fig.2. To do this I tightened two nuts against

A

B

FIGURE 1

FIRST:GLUE TOP PIECESTOGETHER,THEN CUT TOFINISHED LENGTH

%/16” I.D.THREADED INSERT SEE DETAIL

SECOND:GLUE BOTTOMTO TOP PIECES

BASETOPS

18”

1”

2 ”!/2

2”2”

!/2”

6”

BASEBOTTOM ROUND

ALL CORNERS

THIRD:TRIM TOFINAL WIDTH

22”

DETAIL

FIRSTDRILL ”

COUNTERBORE(/16

SECOND,DRILL ” HOLE!/2

!/4”

1 ”#/4

2”

DRILL ” HOLESFOR STOP BLOCKS,

” DEEP

!/8

#/8

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FIGURE 2DRIVE ” I.D. INSERTBELOW SURFACE ”

%/16!/4

TWO”

NUTS%/16

%/16” BOLT

APPLY WAXTO REDUCEFRICTION

DETAIL

!/4”

%/16” I.D.THREADED

INSERT

each other on a 5/16" bolt and then screwedon an insert. To help the insert cut into themaple, I rubbed some candle wax on thethreads of the insert and tightened downthe bolt with a socket wrench, see Fig. 2.

PRESSURE BARS AND CAMSWhen all four of the threaded inserts werescrewed in place, I began work on the pres-sure bars and cams. These pieces are cutfrom three blanks that measure 2" wideand 17" long, see Fig. 3. (Note: These blankscan be built up from two pieces of 4/4 stockor one piece of 8/4 stock — just so they’reabout 11/2" to 13/4" thick.)

PRESSURE BARS. To make the two pres-sure bars (C), cut two of the blanks square(15/8" x 15/8") and to a finished length of 15".Then drill 3/8"-dia. holes 1" from each end toaccept the eye bolts, see Fig. 3.

CAMS. The four whistle-shaped cams (D)can be cut from the other blank. I startedby squaring up one edge of the blank andthen cut it in half lengthwise, see Fig. 4.

LAY OUT CAMS. Next, I made a posterboard pattern of a cam. To achieve the grad-ual tightening action of the cam, the round-ed bottom of each cam is made from two dif-ferent radii (7/8" and 1"). These radii startat two different center points (1/8" apart),and intersect at the bottom. (These tworadii create the cam action that exerts grad-ually increasing pressure on the bar.)

After transferring the patterns to eachworkpiece, I drilled a 1/2"-diameter hole(centered on the 1" radius centerpoint) ineach cam to accept axle pins, see Fig. 4.

CUT SLOT. Before cutting the cams to finalshape, cut a 5/16"-wide slot through eachend of the cam blanks to accept the eyebolts. I did this by standing the piece up onend on the table saw and backing it with a2x4 block, see Fig. 5.

Cut a 13/4"-deep slot centered on eachend, see Step 1 in Fig. 5. To widen the slotto 5/16", move the rip fence slightly awayfrom the blade and repeat the cut. Thenturn the piece around so the opposite faceis against the fence and make another cut.Continue moving the fence slightly andcutting on opposite sides (Step 2) until the5/16" eye bolt slides into the slot.

CUT TO SHAPE. Once the eye bolt fits theslot, cut and sand each cam to final shape.Also, slightly soften all of the sharp edges,see Fig. 6.

CUT AXLE PIN. Next, I cut a piece of 1/2"rod to act as an axle pin through the eyebolt, see Fig. 7. (Shop Note: You can cutthis from a long rod, or from the unthread-ed section of a 1/2" bolt.)

EYE BOLT. The eye bolt is just a standard5/16" x 5" eye bolt purchased from a hard-ware store. After using the jig for a while,I discovered that the eye section started touncurl when extreme pressure was appliedto the cam. To prevent this, I had it weld-ed shut, see Fig. 7.

C

D

FIGURE 3CUT THREE BLANKSTO ROUGHDIMENSIONS 17”

1 ”%/8

1 ”%/8

1 ”%/8

1 ”%/8

1 ”%/8

2”16 ”!/2

CAMS

(ONEPIECE)

13”

1”

1”

PRESSUREBARS

(TWO PIECES)

DRILL ”DIA. HOLES

#/8

FIGURE 6

CUT CAMTO SHAPE

SLIGHTLY SANDALL SHARP

EDGES

FIGURE 7

WELDEYE BOLTSHUT FORSTRENGTH

!/2 %/8” x 1 ”ROD ACTS

AS AXLE PIN

%/16” x 5”EYE BOLT

FIGURE 5

RIPFENCE

USE WOODBLOCK TOPUSH WITH

SET SAW BLADE1 ” HIGH#/4

CENTERFIRST CUT

RIPFENCE

DETAIL

WIDEN SLOTTO ”%/16

21

1 ”#/4

WASTE

D

FIGURE 4 FULL SIZE CAM PATTERN

3” &/8”

CAM!/2”

DRILL ”DIA. HOLE

!/2

!/2”

!/8”

1”

1”RADIUS

&/8”RADIUS

MARK CENTER OF1” RADIUS AND

DRILL ” DIA. HOLE!/2

8”

8”

CUT CAM BLANK IN HALF.THEN DRAW TWO CAMS ON EACH PIECE

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FIGURE 15

1” 1 ”!/2

!/2”

#/4”

CUT OFF 3” LONGMACHINE SCREW,

LEAVE A 1 ”LONG STUD

!/2

SCREW ON STOPNUTS FIRST

STUDDETAIL

POSITIONTEMPLATE FLUSH

WITH ENDS OF BASE

SCREW BRACKETS FLUSHWITH ENDS OF

TEMPLATE

COUNTERSINK HOLESIN TEMPLATE FOR ” x ”

Fh MACHINE SCREWS!/4 !/2

MARK STUD POSITIONTHROUGH SLOT ”DOWN FROM TOP

EDGE OF BASE

!/2 !/4”

BRACKETDETAIL

Plans N O W page 3 © 1999,August Home Publishing Co.

FIGURE 8“COMB” TEMPLATE

4”

NOTE: MAKE TEMPLATE FROM ” MASONITE!/4

FOURTEEN NOTCHES

6” 11 ”!#/16

24” ROUGH LENGTH

FIGURE 11AUXILIARY FENCE

BACK UP WORKPIECEWITH MASONITETO PREVENTCHIPOUT

CUT FOURTEENNOTCHES

INDEXING KEY

TEMPLATEAfter the jig base block and cams werecomplete, I began work on the “comb” tem-plate that guides the router.

This template must be extremely accu-rate or the dovetail joint won’t fit togeth-er correctly. I found that the most accu-rate method of cutting the notches in thecomb was to use a box joint jig. (A box jointjig plan is shown in Woodsmith No. 42.)

CUT NOTCHES. Start by cutting a piece ofMasonite 4" wide and 24" long, see Fig. 8.The next step is cutting the notches. Sincea 1/2" dovetail bit uses a 7/16" (outside diam-eter) router guide bushing, the notcheshave to be exactly 7/16" wide. (Check thewidth cut by your dado blade by making anotch in a test piece and see if your guidebushing fits.)

When the notch width is correct, raisethe blade 1" high and then screw a tall aux-iliary fence to the miter gauge. Now, standthe Masonite on edge and cut a notch 6"from one end, see Fig. 9.

INDEXING KEY. After the first notch iscut, cut a 7/16" indexing key and glue it intothe notch in the fence, see Fig. 10. Oncethe glue dries, trim the top of the key slight-ly and chamfer the edges so the workpiecewill slip over it easily.

Then, move the fence over and screw itto the miter gauge so the key is exactly7/16" from the dado blade. (Note: This dis-tance has to be extremely accurate andmay take some “fine tuning.” The box jointjig shown in Woodsmith No. 42 has anadjustable fence that makes this adjust-ment easier.)

CUT REMAINING NOTCHES. Once the jig isset up, place the first notch over the keyand cut a second notch in the template.(Note: I backed up the workpiece withanother piece of 1/4" Masonite to preventchipout.) Then continue this process untilfourteen notches are cut, see Fig. 11.

To check for accuracy, measure the dis-tance from the first notch to the last. Sincethere are fourteen 7/16"-wide notches andthirteen 7/16"-wide pins, it should measure1113/16", see Fig. 8.

ROUND THE PINS. Once all the notches arecut, I filed the front end of each pin round,see Fig. 12. (Note: The back end of thenotches on most commercial templates arealso rounded, but they don’t have to be tocut dovetails.)

CUT TO LENGTH. To cut the template tolength, place it on the base block with themiddle pin centered on the length, see Fig.13. Then mark and cut the template thesame length as the top of the base.

BRACKETS. The template is attached tothe block with angle brackets. These can bemade from 4" x 4" steel corner brackets.

FIGURE 9AUXILIARY FENCE

6”

&/16” WIDEDADO BLADE

SET BLADE1” HIGH

MASONITE TEMPLATE

FIGURE10

&/16”

CHAMFERTOP

EDGES

NOTE:MOVE FENCE SO KEY ISEXACTLY ” FROMDADO BLADE

&/16

GLUE A ”INDEXING KEY INTO

FIRST NOTCH IN FENCE

&/16

FIGURE 13

WASTE

CENTER MIDDLE PINON BASE BLOCK

CUT TEMPLATEFLUSH WITH ENDS

OF BASE

FIGURE 14ANGLE BRACKET

4”

2”CUT OFFWASTE

1 ”!/4

WIDTH OF SLOTSHOULD MATCH

DIAMETER OFHOLE IN BRACKET

FIGURE 12

FILE THEFRONTENDS

ROUND DETAILWASTE

&/16”DIA.

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Plans N O W page 4 © 1999,August Home Publishing Co.

FIGURE 18

DRILL ASERIES OF

” HOLESTO CREATE

SLOT

#/16

SCRAPSUPPORT BLOCK

DETAIL CUT STOP BLOCKOFF EACH END!/2”

#/16”

!/2”1”

1 ”#/4

#/8”

WASTE

FIGURE 17NOTCH

” OFFBOTH ENDS

&/16

SET SAW BLADEHEIGHT TO ALIGN

WITH RABBET

RIP FENCEDETAIL

&/16” &/16”

#/8”

MAKE MULTIPLEPASSES

TO REMOVEREMAINING

WASTE1 2

FIGURE 16

RIPFENCE

2 ”!/2 8”

SET SAWBLADE” HIGH,#/8

RIP FENCE

1”

1”#/8”

#/8”

DETAIL

1 ”#/8

RABBET

21 3

Start by hacksawing one “leg” on eachbracket to 2" long, see Fig. 14.

Then cut a 11/4"-long slot up from the cut-off end. Depending on the brand of cornerbracket you buy, you will probably be cut-ting up through a mounting hole. Cut theslot to width to match the diameter of thehole. On some brackets these holes are offcenter and the slot should be cut off centerto match.

After the slots are cut, position thebrackets on the ends of the template andcountersink holes in the template formachine screws, see Detail in Fig. 15.

STUDS. Once the template is screwed tothe brackets, two studs are mounted in thebase block to position the brackets. To dothis, position the template flush with theends of the block and mark the slot posi-tions on the front of the block, see Fig. 15.

The studs are created by tightening twomachine screws into the block and thencutting off their heads, see Detail in Fig. 15.(The diameter of the studs should matchthe width of the slots in the brackets.)

Shop Note: Before tightening the screwinto the block, thread two nuts onto thescrew to act as stops for the template, seeDetail in Fig. 15.

STOP BLOCKSThe only thing left to make are the stopblocks. These position the workpieces inrelation to each other and to the template.

CUT THE RABBET. Start by cutting a pieceof stock to a width of 21/2" and length of 8".Then cut a 3/8"-deep by 1"-wide rabbet alongone edge, see Steps 1 and 2 in Fig. 16. Nextcut the piece to a finished width of 13/8", seeStep 3.

END NOTCH. When cutting dovetails, thetwo workpieces have to be offset 7/16" fromeach other. To allow for this offset, cut a7/16"-wide notch at both ends of the stopblock to produce a 7/16"-long finger, see Fig.17. After cutting the notches, check thelength against the comb template - the “fin-ger” should be exactly as long as the widthof a pin on the comb.

Shop Note: It may be easiest to cut thefingers just a hair longer than 7/16" and filethem down to exact size.

ADJUSTMENT SLOT. To make the blocksadjustable, I cut 1"-long screw slots bydrilling a series of 3/16" holes, see Fig. 18.Then cut a stop block off each end.

FINAL ASSEMBLYAfter the stop blocks are made, you canassemble all the pieces, see Fig. 19. To start,screw the stop blocks down with sheetmetal screws into the pre-drilled holes sothe shoulder of each stop block is 61/8" fromthe center of the jig. (This may have to beadjusted later, see page 5.)

Then add the springs, bars, and cams.And finally, the template is held tightly tothe studs with washers and wing nuts.

FIGURE 19FENDER WASHERS

FINAL ASSEMBLY

SCREW DOWN SOSHOULDER OF STOPBLOCK IS 6 ” FROM

CENTER OF BASE!/8

#/8” I.D. x 2”LONG

COMPRESSIONSPRING #10 x ”

PAN HEADSCREW

#/46 ”!/8

6 ”!/8

COMPRESSIONSPRINGS

FLAT WASHER

WING NUT TO FIT STUD

%/16 %/8” I.D. x 1 ” O.D.FENDER WASHERSTO PREVENT WEAR

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Plans N O W page 5 © 1999,August Home Publishing Co.

ALL PIECES AREINSIDE FACING UP

DETAIL

FRONT

JIGBASE

SIDE

DRAWERFRONT

STOPBLOCK

DRAWERSIDE

DETAIL

FRONT

JIGBASE

SIDE

MAKEENDS LEVEL

Cutting tight dovetail joints with arouter and template is easy - but itrequires a little planning ahead. It’sbest to plan the dimensions of thecabinet opening ahead of time toaccommodate drawers that are joinedwith router-cut dovetails. That is, thewidth (height) of the drawer fronthas to be a multiple of 7/8". (This pro-duces a joint that’s symmetrical bothon the top and bottom edges, see thephoto.)

Once the width of the drawer fronts isdetermined, cut the drawer’s side and backpieces to the same width. (Note: All of thisassumes that the drawers are flush frontdrawers. See page 7 for information onmaking rabbeted front drawers.)

LENGTH. As for length, cut the pieces tofit the cabinet openings (taking into con-sideration any clearance). Also, to makesure the corners are square, check that thedrawer front and back are equal lengths,and the drawer sides are equal lengths.

LABEL PIECES. Once all of the pieces arecut to finished size, lay them out and labelthe bottom edge of each piece. Also, num-ber matching corners, see Step 1.

ALIGNMENTSetting up the jig takes some trial anderror, so don’t start with the finished pieces.I work with scrap that’s the same thick-ness and width as the drawer pieces.

MOUNT PIECES. Start by mounting a testdrawer side under the front pressure barand a test drawer top under the top pres-sure bar with the bottom edges tightagainst the left-hand stop block and theinsides facing out, see Step 2. (This can beconfusing since it’s opposite the way thepieces will be in the drawer.)

After the drawer front is clamped down,reposition the drawer side so its end is levelwith the drawer front, see Step 3.

ADD TEMPLATE. Next, mount the“comb” template on the jig.Everything is okay if the bottomedge of the drawer side is centeredon the first notch of the template,see Step 4. Now hold the templatedown (flat) on the drawer front andtighten the wing nuts, see Step 5.(The location of the stop nuts on thestuds may take some adjustment,see box on page 6.)

ROUTER SET-UPThe router is guided in and out of the tem-plate with the aid of a guide bushing, seeStep 6. This is a metal “collar” that mountsto the router base.

Next, mount a 1/2" dovetail bit in therouter, making sure the bit is centered inthe collar of the guide bushing. If it’s not,adjust the router’s plastic base slightly. Asfor the depth of the bit, I start with it 1/2"deep (from the base), but this may varydepending on the bit, see box.

ROUTING THE PIECESNow the pieces can be routed. To preventchipout, start by making a light scoring

Dovetails: Step-By-Step

BOTTOMEDGE

ADJUSTABLESTOP BLOCK

TEMPLATE

TOP VIEW DRAWERSIDE

!/2”

&/16” GUIDEBUSHING

!/2” DOVETAILBIT BUSHINGSTOP NUTS

Start by laying out the drawer pieceson a bench with the insides facing up.

To avoid confusion, label all pieces andnumber the matching corners.

Clamp a drawer side under front bar.Then clamp a drawer front on top of

jig tight to the drawer side. Insides faceout and bottoms to the left.

Next, loosen the front pressure barand reposition the drawer side so the

top end is perfectly level with the top of thedrawer front.

1 2 3

Mount 7/16” guide bushing onto therouter. Then raise bit 1/2” from router

base as a starting point. It may have to beadjusted slightly later.

6End of drawer front should start outcentered between front and back of

notch at both ends of jig. To adjust, changeposition of the stop nuts.

5Place template over studs and checkthat the bottom edge of the drawer side

is centered on the first notch. If it’s not,adjust the stop block.

4

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pass from right to left, see Step 7.Then gently move the router in and out

of the fingers, moving from left to right,see Step 8. You should be able to feel theguide bushing stop at the back of eachnotch. After routing, but before removingthe pieces from the jig, check that you’verouted each socket evenly, see Step 9.

ROUTING REMAINING JOINTS. At thispoint, you’ve routed the joint at the leftfront corner of the drawer. (It’s markedNo. 1 in Step 1.) Next rout the right rearcorner joint (marked No. 3) using the sameprocedure. Mount the drawer side on thefront of jig, the drawer back on the top ofjig - with the bottom edges against the stopon the left and the insides facing out.

The other two joints (No. 2 and 4) arerouted with the pieces tight against thestop block on the right side of the jig. Again,always clamp the drawer side to the frontof the jig, the inside of the pieces facingout, and the bottom edges against the stops(this time on the right).

When routing on the right side, followthe same procedure. Make a light pass fromright to left and then move the router in andout of the notches from left to right.

BOTTOM GROOVE. When all the joints arerouted, all that’s left is to cut the groovesfor the drawer bottom, see Step 10. Cutthe groove so it’s centered on the bottomsocket of the drawer front. Then it will behidden by a pin on the drawer side.

MOVE ROUTERIN AND OUT

BIT!/2” DOVETAIL BIT

MAKE LIGHT PASSTO PREVENT CHIPOUT

SOCKETS

PINS

DETAIL

BOTTOMSOCKET

RIPFENCE

SIDE

TABLESAW

FRONT

BOTTOMGROOVE

TROUBLE SHOOTINGSetting up to make router-cut dovetails isalways a trial and error effort. There’s usu-ally lots of fiddling around with trial piecesand readjusting to get a perfect fit.

TOO LOOSE. If the joint is so loose thatthe pieces wiggle around when they’re puttogether, the depth of cut is too shallow,see first photo below. Increase the depth ofcut about 1/32" and try again.

TOO TIGHT. If a trial cut is so tight that thepieces can’t be tapped together, the routerbit is extended out too far from the routerbase. Decrease the depth of cut about 1/32"and try again.

TOO DEEP. If the pins on the drawer sidesgo too far into the sockets on the drawerfront, the sockets are too deep, see middlephoto on right. To correct this, move thetemplate out (toward you) by turning thestop nuts on the studs counter-clockwise.(Be sure to adjust the nuts on both ends ofthe jig.)

Note: You may want the pins to berecessed from the ends of the sockets about1/32". This helps when sanding the jointsflush later. (See Tips, page 8.)

TOO SHALLOW. If the pins don’t go farenough into the sockets, move the tem-plate in (away from you) by turning thestop nuts clockwise.

OFFSET. After the joints are cut andtapped together, sometimes the top edge ofthe drawer front doesn’t align with the topedge of the side, see third photo.

If both the top and bottom edges are off-set equal amounts, there could be a coupleof things wrong. First, the edges of bothpieces have to be tight against the stopblock. There might be some sawdustbetween the workpiece and the stop block.

Second, the offset on the stop block maynot be exactly 7/16". If it’s a little more thanthat, you might try adding a layer or two

of masking tape to the “finger” on the stopblock.

Note: The end of the stop block should becentered on the first notch of the template,see Step 4 on page 5. If it’s not, the topedges of the two pieces will be aligned, butthe joint won’t be symmetrical on the topand bottom edges.

OTHER PROBLEMS. Most other problemsare usually caused by the pieces not beingclamped down in the jig so they are flushacross the top, or because they move out ofposition as they’re being routed.

TOO LOOSE. If joint is tooloose, increase bit depth.TOO TIGHT. If the joint is tootight, decrease depth.

TOO DEEP. If pins go deep,move template toward you.TOO SHALLOW. If not deepenough, move toward jig.

OFFSET. If the pieces don’talign, they may not havebeen tight against stops. Orstop offset may not be 7/16”.

To prevent chipout on drawer side,start by making a light pass from right

to left. This “V” groove establishes a cleanshoulder line.

Next, move the router from left to rightworking in and out of the notches.

Push the router into each notch until thebushing hits the bottom of notch.

Finally remove the template andcheck that all of the sockets and pins

are uniform. Opposite joints are cut on theright side of the jig.

After all joints are routed, cut bot-tom groove on saw in two passes to

match drawer bottom thickness. Center thegroove on the bottom socket.

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Page 7: PlansNow - Dovetail Jig

Plans N O W page 7 © 1999,August Home Publishing Co.

RABBETED DRAWERSMaking the dovetail joints for a drawerwith a rabbeted front is a little differentfrom routing a flush front drawer. You haveto take into consideration the lip aroundthe outside of the drawer front.

LAYING OUT. When you lay out the pieces,the width of the drawer’s back and sides hasto equal the shoulder-to-shoulder width ofthe drawer front instead of the overallwidth, see Step 1. And the length of theback equals the shoulder-to-shoulder lengthof the front, not the overall length. (I cutthe rabbets before routing.)

Note: Once again, it’s best if the cabinetis designed so the width of the drawer backand sides is a multiple of 7/8".

SPACER. When clamping the drawer frontto the jig, you also have to take into con-sideration the rabbet. To correctly positionthe shoulder in relation to the template, Iput a spacer between the drawer front andthe stop block, see Step 2.

To determine the thickness of this spac-er, subtract the width of the rabbet from 7/8"(since a pin plus a notch = 7/8"). For a 3/8"rabbet then, you will need a 1/2" spacer, seeStep 2.

END ALIGNMENT. On the end of the draw-er front, the shoulder of the rabbet (notthe end) has to be aligned with the front ofthe jig. To set this up, cut a matching rab-bet in a piece of scrap and clamp it underthe front pressure bar. Then bring thedrawer front up tight against the rabbet inthe scrap, see Step 3.

ROUTING SIDES. After routing the draw-er front (Step 4), remove the front fromthe top of the jig and replace it with a pieceof scrap, see Step 5. Then bring the draw-er side up tight against the front of the jigand the scrap. Since the side piece doesn’thave a rabbet in it, you can rout it withouta spacer.

BACK CORNERS. The back corners (wherethe drawer back meets the sides) are cutwith the flush dovetail technique, see page5.

BOTTOM GROOVEThe rabbet also has to be considered whenlocating the groove for the bottom in allthe pieces. To do this, I just avoid the rab-bet by making a little fence for the tablesaw that fits under the rabbet, see Step 6.Then the groove will be cut the same dis-tance from the shoulder on the drawer frontas it is from the bottom on the back andsides, see Step 7.

When cutting a groove for a 1/4" plywoodbottom, I do it in two steps. First, adjustthe fence so the cut will be slightly off-cen-ter on the bottom socket. After making apass with all the pieces, move the fenceslightly until the groove is centered on thesocket and wide enough to accept the 1/4"bottom. Then make another pass.

RABBETEDFRONT

BACK SIDE

SHOULDER

DETAIL

FRONT

JIGBASE

DRAWERFRONT

!/2”SPACER

DRAWERFRONT

SPACER

DETAIL

FRONTSCRAP

JIGBASE

SCRAPPIECE WITH

” RABBET#/8

#/8”

MOVE ROUTERIN AND OUT

!/2”DOVETAIL

BIT

SCRAP

SCRAPPIECE

ROUT PINS ONDRAWER SIDES

C-CLAMP

!/4”MASONITE

BLOCK

RIPFENCE

LEAVE FENCEAND BLOCK INSAME POSITION

AS STEP #6

SHOULDER

RABBETEDDRAWER FRONT

TAP PINSINTO SOCKETS

UNTIL SIDE IS FLUSH

When laying out for a rabbeted draw-er, the width of the sides and back

should equal the shoulder-to-shoulderdimension of the front.

Cut the rabbet on the drawer frontfirst. Then, for a 3/8” rabbet, slip a 1/2”

spacer between the bottom edge of the draw-er front and the stop block.

To keep the shoulder of rabbet alignedwith front of jig, clamp temporary rab-

beted piece under front bar and bring endof drawer front up tight.

Cut the sockets in the drawer front bymoving router from left to right. Work

in and out so the guide bushing bottomsout in all of the notches.

Remove the drawer front and replacewith a piece of scrap. Then rout the

pins on the ends of the drawer side the sameas on a flush front drawer.

To cut groove for bottom, nail a stripof Masonite to the bottom of a block

and clamp to fence. Then run the rabbetshoulder against the Masonite.

To cut the bottom groove on the insideof the drawer sides and back, leave the

rip fence and Masonite spacer in the sameposition.

Tap drawer sides into drawer frontuntil the pins fit flush with the shoul-

der. The back joint is cut the same as for aflush front drawer.

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6

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Page 8: PlansNow - Dovetail Jig

Tips for Dovetailing

Plans N O W page 8 © 1999,August Home Publishing Co.

DEPTH-SETTING GAUGEOne of the most difficult things about set-ting up a router to cut dovetails is adjust-ing the bit to the correct height. If the bitis just a hair too high, the joint will be tootight; just a hair too low, and it’s too loose.

BUILD A GAUGE. Once the bit is set to thecorrect level, it’s worth taking a few min-utes to build a simple depth-setting gauge.Then, whenever you use that bit, you caneasily set it to the correct height.

When the router was set up and readyto go, before cutting the dovetails, I firstmade a gauge (for future use) by cutting anotch in a long scrap of hardwood. (Startwith a long block and cut it shorter later.)

But there’s a problem here. You can’trun the router over the block because theguide bushing around the router bit blocksthe bit from cutting. (It’s not a problemwhen using a template since the templatekeeps the bushing up off the workpiece.)

DADO FIRST. To get around this problem,start by cutting a 3/4"-wide dado across theblock. Cut it a little deeper than the heightof the bushing, see Step 1.

ROUT DOVETAIL NOTCH. After cutting thedado for the bushing, rout a wide dovetail-shaped notch across the block. To do this,I clamped the block in a vise and ran thebushing against the left shoulder of thedado, and the back out against the rightshoulder, see Step 2.

USING THE GAUGE. Now, whenever youwant to set up to rout dovetails, put theblock on the router base and raise the bituntil it’s even with the top of the notch.

FITTING DOVETAIL JOINTSHow tight should a dovetail joint be? Agood fit shouldn’t be so loose that you canpush the pieces together with your hands.It should take some light tapping to getthem together.

However, even with light tapping, it’sbest to apply even pressure across thewhole joint to prevent the pins from split-ting out. I place a block of hardwood overall the pins on the drawer side and thentap until the pins are seated in the bottomof the sockets.

STANLEY HAMMER. Instead of using asteel hammer or wooden mallet, I’ve foundthat a Stanley “Dead Blow” hammer worksnicely for most joint assembly tasks. Thesehammers are made of black plastic and thehead is filled with oil and shot. They can beused with quite some force and still notdent the wood. They’re available at mosthardware stores and home centers.

NO CLAMPS. One advantage of havingtight fitting joints is that you won’t needclamps to hold the drawer together whilethe glue dries. (Clamps can sometimes havethe negative effect of pulling the drawer outof square.) If the joints are cut with a tightfit, just check the drawer for square as soonas the joints are tapped home. Then allowthe drawer to dry on a flat surface.

GLUING DOVETAIL JOINTSHow much glue should be applied to a dove-tail joint? And where should you put it —on the pins or in the sockets?

TIGHT JOINT. If the joint fits tightly, youdon’t need much glue. I usually squirt onedot of yellow glue on the back side of eachpin. Then when the pin seats in the sock-et, the glue sort of squishes its way aroundthe pin and the socket.

LOOSE JOINT. If the joint is a little looseyou may need to brush the glue all the way

around the pins and also in the sockets. Iusually use a small artist’s brush to do this.The problem is that there are a lot of sur-faces to cover and the glue can start settingup before you can get the drawer assem-bled. It’s a good idea to have some help tospread the glue quickly.

SANDING THE JOINT SMOOTHThe perfect dovetail joint should fit togeth-er tight, flush, and there shouldn’t be a lotof excess glue squeeze-out. That’s the ideal.But in reality, there may be some finishingwork to do on a dovetail joint after assem-bly.

In fact, since I know the joint won’t beperfect, I plan the fit of the joint so it hasto be sanded down exactly smooth. Theonly question here is: Should the joint becut so the pins stick up a little from thesurface, or so the ends of the sockets stickup a little?

SANDING PINS. If the joint is cut so thepins stick up, you have to sand the wholedrawer side to keep it a uniform thickness.If you only sand down the face of the pins(near the joint), the middle section of thedrawer side will be thick and cause prob-lems when it’s time to fit the drawer in thecabinet.

SANDING DRAWER ENDS. If the joint is cutso the pins are deep, then you only have tosand the ends of the sockets (the ends of thedrawer front and back). But this createsanother problem. The front and back areusually cut to length to fit the opening inthe cabinet so there will be a small gap oneither end. If you sand after the drawer isassembled, the gaps can easily get too large.

However, I usually follow this secondmethod and cut the joint so the pins areabout 1/32" too deep. But I take this intoconsideration when measuring and cuttingthe drawer front and back to length. If thepins are set 1/32" too deep, the length of thedrawer front and back will be shortened1/16" when both ends are sanded.

1

2

#/4”!/4”

&/16”GUIDE BUSHING

DOVETAILBIT

ROUTDOVETAILNOTCH IN

TWO PASSESCUT OFF

WASTE AFTERROUTING

WHENRESETTING

RAISE BIT UNTILEVEN WITH TOP

OF NOTCH

NOTE:UNPLUG ROUTER

WHEN SETTINGDEPTH OF BIT

DRAWERSIDE

DRAWERFRONT

PLACE HARDWOODBLOCK OVER ENTIRE

JOINT WHEN TAPPINGPIECES TOGETHER

SIDE

FRONT

SETPINS

”INTOSOCKETSANDSANDFLUSH

!/32

BELT SANDUNTIL FLUSHWITH SIDE