How to Build a Barristers Bookcase.pdf

How to Build a Barrister's Bookcase

Stackable cases with retractable overhead doors

by Jeff Greef

Jeff Greef's walnut lawyer's cabinet resembles a garage for books, complete with

overhead doors. A pair of carcase modules capped with a top unit (left) waits to be

stacked onto another pair resting on a base unit (right). Greef waxes the back side of

one of the retractable doors, which is guided by a simple pulley mechanism that's pat-

terned after the guide system used in the 1906 cabinet in the photo below.

mong the victims of California's 1989 Loma Prieta earth-

quake was a sectional bookcase (also known as a lawyer's

or barrister's bookcase) belonging to a friend of mine.

When she asked me to rebuild it, I inspected the parts she had laid

in her garage. Damage was minimal, mostly disassembled joints

rather than broken wood, so repairs would be easy. The bookcase

was composed of separate cases stacked together and aligned by

tongues, grooves, dowels and holes. There were also pedestal and

crown units that attached to the bottom and top of the assembled

cases. Each shelf module had a glazed door,

which pivoted at its top, then slid into a pock-

et above the opening.

I also saw something that mystified me—a

curious system of metal bands, wooden chan-

nels, and small wooden pulleys, around which

the bands were wrapped. Closer investigation

revealed that the purpose of the mechanism

was to guide the doors, so they would slide

parallel to the case sides and not turn askew

and bind with the carcase when opened. I was

so intrigued by the guide system on this 80-

year-old set, I resolved to build a stacking

bookcase with a similar wood and metal

mechanism for myself (see the photo above).

The refurbished bookcase, labeled "The

Viking," was patented and built by Skandia

Furniture Co. of Rockford, Ill (see the photo below). Patent dates

on the label, and the owner's recollection, put the time of the case's

manufacture around 1906.1 was disappointed at first to see the ba-

sic construction for the carcase modules was rabbets and nails. But

practical experience contradicted my negative judgment—all the

nailed joints survived the thrashing of the earthquake, whereas half

the hide-glued joints broke. After reconsidering, I decided to use

the same construction as Skandia with only minor changes. I broke

the project down into four assemblies: top and bottom units, car-

cases, doors and parallel mechanisms.

Materials and case construction

All visible wood on the Skandia cabinet was

darkly stained oak, and all the unexposed

parts were made from either poplar or alder.

For my case, I used air-dried California black

walnut for the primary wood and poplar for

the secondary wood. I edge-glued walnut to

poplar for the cabinet bottoms (bookshelves)

and for the rear rail of the top unit. Instead of

gluing up the carcase sides, which had

cupped on the oak original, I used single

pieces of quartersawn walnut. I grain matched

the sides to create a continuous pattern from

top to bottom and did the same for the walnut

end caps and door stiles. I used poplar for the

stretcher and back rail of the bottom unit

and also for the carcase tops, which serve

as the base for the door guides. I also used

poplar for the pivot-post guide channels

and all the wooden pieces needed to

make the parallel mechanism.

drilled a mating hole in their bottoms to

keep the stacked components aligned.

Doors— Although the Skandia door-frame

moldings -were probably shaper cut, I cut

the sticking on my router table. To make

the recess for the glass, I rabbeted the back

of my door frames with a set of reversible

cope-and-stick router cutters. Because I

don't like to rely on a stub tenon alone, I

dadoed out the mating frame parts and in-

serted solid loose tenons (see the top pho-

to). I sized the door's width, leaving about

in. clearance on each side and rabbeted

the back of the door stiles to mate with the

rabbet on the end caps. Just before instal-

lation, I trimmed the door's top and bot-

tom to fit the case opening. To retain the

glass, I nailed a -in. darkly stained poplar

molding around the inside of the frame.

One of the two pivot posts on each door

must be retractable to install the doors in

their guide channels. On one side of each

door, I bored a -in. hole for the fixed

post, which fits tightly with no adhesive.

For the spring-loaded post, I bored a

in. hole 2 in. deep and then bored two

-in. holes right next to each other in the

rear face of the door frame directly over

the long hole. I then chiseled the two

holes to form a beveled slot (see the bot-

tom photo at left). Next, I inserted a spring

in the pivot-post hole, followed by a 2 in. length of -in.-dia.

brass rod. I pushed the rod in until the spring was fully com-

pressed, and then I scribed a mark on the rod through the beveled

slot. I removed the brass rod, bored a hole at the scribe and

tapped threads to accept a brass machine screw, which acts as a

stop to retain the spring-loaded pin.

Top and bottom units — The shaped

front rail (fascia) of the top and bottom

units adds a nice profile to an otherwise

rectilinear construction (see the drawing

on the facing page) I cut the coves on the

rails by clamping an angled fence on my

tablesaw and running the workpiece over

the blade several times taking a -in.-

deep cut with each pass. To make way for

the tops of doors as they are swung open,

I also coved the bottom of each walnut

shelf front and the underside of the cap

edge of the top unit. Using my miter

gauge on the tablesaw, I crosscut the an-

gled groove that receives the front rails in

both the top and bottom units' sides. The

inside grooves for the rails on the bottom

unit's sides can go right across the piece

and not be seen, but not so on the top

unit's sides. I stopped the top's grooves

for the front and rear rails and likewise for

the grooves that hold the raised panel top.

Next, I cut the tenons on the ends of the

rails in two passes on the tablesaw: one

with the piece flat to define the shoulder;

and the other with the piece upright to cut the tenons' cheeks.

Then I fitted the rails' tenons into the grooves and scribed the rail

profile onto the sides, I found that it was much easier to match the

leading edge of the sides to the contour of the rails than vice ver-

sa. After bandsawing the front edges of the sides, I scraped

and sanded them smooth. To complete the joinery for the top

unit, I cut shallow, stopped rabbets in the sides to receive the cap

edge. To hide this joint from the front, I cut -in.-long tongues on

the ends of the cap edge to overlap the joint (see the drawing on

the facing page).

To make the bookcase door frames, the

author used his router table and a set of

reversible cope-and-stick cutters, and then

he strengthened the joints with solid loose

tenons. The stiles and the rails are also

rabbeted for the glass.

By spring-loading one of the -in.-dia.

brass pivot posts in each door, the

author can install or remove the doors

with ease. A brass setscrew, which threads

into each spring-loaded post, retains the

post in the frame. To avoid weakening

the door's stiles, he chiseled the setscrew's

beveled access slots in the top rail.

Making the parallel mechanism

As shown in the drawing on p. 54, the parallel mechanism consists

of three pans: guide channels along the carcase sides, a pulley and

a track at the back, and two steel bands. Both pivot posts protrude

through holes in the front end of the bands. Each band follows its

own guide channel, wraps around a pulley, and meets in a com-

mon track in the rear where the ends of the two bands are con-

nected. When one band moves, the other moves an equal amount,

thus the door stays parallel. And since the bands slide inside the

guide channels and the rear track, they can't buckle.

Carcases— Though the basic construction of the carcases is sim-

ple rabbet joints (which I screwed together rather than nailed), the

alignment of the numerous rabbets is involved. I scrutinized the

Skandia cabinets and dimensioned my carcase to make assembly

as easy as possible (see the drawing). The solid-wood sides have

face-frame-like front end caps that have a rabbet onto which the

doors overlap. This overlap inhibits dust intrusion, hides the door

guides and stops the door from swinging inward. Another rabbet

crosses the top of the end caps to make way for the doors to slide

by. The end caps run the full height on the front of the sides, mi-

nus in. at the top. This in. equals the length of the tongue at the

top of the sides that joins each carcase module to the case above

it or to the top unit. The bottom of the top unit's and cases' sides

must, therefore, have a corresponding groove.

The carcase bottoms fit into rabbets in the sides and are notched to

fit around the front caps, as shown in the drawing. The -in. tongue

at the front of each bottom (edge-glued walnut piece) overhangs the

end cap much like the cap edge on the top unit. I also rabbeted the in-

side of the carcase sides for the poplar tops and for the -in. plywood

backs. Finally, I installed a dowel in the top of each front end cap and

Guide channels —The channels along the carcase sides serve two

functions, as shown in the drawing detail on p. 54. They support

the pivot posts as the door slides as well as guide the bands. Al-

though each Skandia channel was made from one solid piece, I

made mine in two parts, as shown in the detail. I routed track for

the bands with the thinnest (0.050-in.) slot cutter my tool man

could find. To use his three-winged cutter, I needed a special ar-

bor as well. (Arbors and cutters are available from Steve Cash, San-

ta Cruz Saw and Tool, 1115 No. 9 Thompson Ave., Santa Cruz, Calif.

95062; 408-462-6936.) I crosscut the channels just shorter than the

side width (to allow for shrinkage of the case's sides) and bored

and countersunk oversized screw holes within the guide channels.

I set the channels in place and used the holes to guide pilot holes

into the sides before I screwed the channels

to the case, as shown in the photo at right.

the band between two blocks of wood and

taping the end of the band over a guide

hole bored in one of the blocks, I was able

to clamp the pieces in my vise and bore

through the guide hole. Once the bands

were bored and back in place, I trimmed

the ends with tin snips, so they would not

protrude beyond the closed doors.

Pulleys, corner block and rear track—

At the rear of the guide channels, there are

two different blocks to guide the bands. In

the left corner, there's a wooden pulley

block; in the right corner, a curved guide

block. For the curved guide, I just band-

sawed a quarter of a l-in.-radius circle in a

2x2 block. I cut the pulley from a 2x2

block using a standard hole saw. I found

that the plug from a -in. hole saw fit

snugly within the hole cut by a -in. hole

saw. To trim the pulley down for a looser

fit, I put a bolt through the pulley's center

hole, chucked the bolt in the drill press,

and on low speed, took a file to the

perimeter of the pulley. For the rear track piece, I first tapered the

leading edge on the jointer from 2 in. wide at one end to in. wide

at the other. Next, I set up the slot cutter in my router table and cut

slots to house the bands. I carefully adjusted the height of the cut-

ter to make the slots tangent to the pulley hole. Then I cut the

tracks in the pulley corner block. To center the pulley in its hole, I

used the hole-saw arbor bit and a pulley as a center punch. Final-

ly, I screwed a pulley block, curved guide block and track piece to

each case top.

To allow for wood movement in the

side of his case, Greef fastens a guide

channel by first drilling oversized holes

in the guide. Then he installs three screws

within the channel using needle-nose

pliers and a tiny screwdriver. To complete

the door-guide system, he glues a pair of

walnut skids at the front of the case and a

pair of cork bumpers at the rear.

Installation— After chiseling slots in the

back of the end caps in line with the side

channels to allow clearance for the pivot

posts, I trimmed the posts to length and fit-

ted the door in place. Then I inserted the

fixed post in a band hole, retracted the oth-

er spring post and released it into its hole.

The door slid smoothly, quietly and paral-

lel along the guides. Out of the corner of

my eye, I saw the Viking smiling from the Skandia cabinet's label.

Final assembly

After installing all the doors, I applied finish to the individual

bookcase sections. To mount the bottom edge of the lowest case's

sides to the bottom unit, the Skandia cabinets had used separate

tongues and arc-shaped slots, which resembled biscuits. In keep-

ing with the original construction, I used my plate joiner to install

two biscuits in each bottom side to align the carcase above. I then

stacked all the shelf cases on the base unit and placed the crown

unit on top. With the bookcase put together, I noticed that when

each door was opened, the rabbet on the door's edges bore down

on the front end of the guide channel. The channel is about in.

thick at this point, and I recalled several of the originals had

cracked there. To avoid this, I installed rubbing skids on the case

top where the back sides of the door stiles contact the guide chan-

nels. I also added cork door bumpers at the rear of each case. Be-

fore placing any books on the shelves, I waxed the guide chan-

nels, pulleys, door edges and pivot posts. Because the original

Viking bookcase survived this long, I figured that earthquakes not

withstanding, my bookcase should outlive me.

Bands— After experimenting with a variety of banding materials, I

ended up using -in.-wide spring banding from an old Stanley -

in. by 12-ft. measuring tape (not the tape measure itself, but the

spring steel at the end of the tape). The springs are thin and strong,

and their cupped cross section keeps them rigid when straight. I

cut two bands slightly longer than needed for each mechanism.

Then, after I scuffed the paint off the ends and cleaned the mating

surfaces with solvent, I epoxied the band ends together. Next, I fed

the band assembly into the guide systems and extended the two

bands beyond the front of the channels to mark the pivot-post hole

locations. Then I removed the bands to drill the holes.

Boring holes through brittle spring steel is difficult. My first at-

tempts using the drill press yielded shattered metal. But, by placing

Jeff Greef of Santa Cruz, Calif, is a woodworker and journalist.

Simple guides align overhead doors

by Alec Waters

Retractable overhead doors used in tradi-

tional lawyer's bookcases are a handsome

way to keep your books dust free. But many

woodworkers are reluctant to make book-

cases like this because they are intimidated

by complex door-alignment mechanisms.

Over the years, several guide systems have

evolved for keeping doors straight and par-

allel to their tracks. And fortunately, for

those who don't want to build exotic rack-

and-gear or pulley-actuated retractors, a

couple of these guides are very simple.

Jeff Greef of Santa Cruz, Calif., discovered

a fairly common scissor-guide system in

many antique barrister's bookcases. The

scissors are amazingly simple; they are at-

tached to the back side of the top of each

door, crisscross to form an "X" and then

connect again to the rear of the case (see

the drawing at right). The curve at the ends

of the bars is critical because the ends must

slip easily through the eyescrews when the

door is opened and closed. A pair of pivot

posts and guides enable the doors to swing

open and support the top of the door,

when it's retracted. Of course, the bottom

of the opened doors must be held up by

guides or cleats on the case sides.

For his bookcase, Greg Moore of Comox,

B.C. Canada, made a single carcase with

shelves rather than individual stacking shelf

units. Instead of using dowel, biscuit or

mortise-and-tenon joinery for the case,

Moore cut finger-like ends in the shelves,

bottom and top to penetrate the laminated

sides of the case. To create the spaces in

the case sides for the fingers, he staggered

the lengths of adjacent oak strips before

gluing and splining them with plywood.

Moore chose a basic pin-and-slot arrange-

ment to hang his doors. He routed stopped

grooves along both edges of each door to

receive brass pins that project from the

case sides. When the doors are closed, they

hang on the pins, and when open, the end

of the groove functions as a stop, so the

doors can't be pushed all the way into the

cabinet. Tight clearances keep the door

from jamming (see the drawing at right).

So the door can be removed or installed

on the case pins, Moore chiseled an escape

slot in each groove. He located the pins so

the distance from the top of each pin to the

bottom of the shelf above it equals the

thickness of the door frame plus in. He

also fastened a pair of horizontal cleats to

the case sides to help suspend each door

when opened. A screw-head slot superim-

posed over a groove in one end of each

cleat lets the case sides move freely during

seasonal moisture changes. Moore also left

clearance between the rear end of the

cleats and the back of the case to accom-

modate side shrinkage. Although Moore

first feared that without stops, the doors

would swing in and out of the cabinet like

saloon doors when closed, he discovered

that when released from a horizontal posi-

tion, each door automatically comes to rest

when it reaches a vertical state. A cushion

of air that gets trapped inside the cabinet

provides the braking action.

With both the scissor guides and the

pin-and-slot system (when the components

are precisely aligned and properly waxed)

the doors slide smoothly and remain paral-

lel. I suppose that there is one drawback,

though; now that I know about these sim-

ple guide systems, there's no excuse for

omitting retractable doors in the next book-

case I build.

Alec Waters is an assistant editor for FWW.

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