THE SLED SUPPORTS WARPED BOARDSA jointer is the proper tool for flattening a single face of a board. But many woodworkers lack a jointer that canhandle wide boards. This sled supports a cupped or bowedboard so the planer can act like a jointer, producing a flatand straight surface. The board then can be flipped overand planed conventionally to mill it to final thickness.

58 F I N E W O O D W O R K I N G Photos: Mark Schofield

orking with wide lumber is a joy:The figure and color are seamless,

just as it came off the log. But manywoodworkers face a problem when itcomes to flattening one side of a wideboard. We can rip the board into narrowerpieces, use a 6-in. or 8-in. jointer, and thenrejoin the parts, but a perfect match is not al-ways possible. The alternative is to hand-plane one side flat, a laborious process.

Now, I like handplaning as much as thenext guy, but I prefer to save my energyand let machines dimension lumber. To thisend, I designed an adjustable sled that al-lows me to face-joint lumber with a thick-ness planer. The sled is reliable and quick toset up and adjust without using any tools.To make it, you first need to determine themaximum width the bed of your planer

Flatten BoardsWithout a Jointer

A sled lets you use just your planer to mill lumber to any thickness

B Y K E I T H R U S T

Bowed orcupped board

Adjustablesupport block

W

J A N U A R Y / F E B R U A R Y 2 0 0 5 59Drawings: John Hartman

will accept and how long a sled you want.My 121⁄2-in. portable planer could handle asled of the same width, but to avoid havingtoo tight a fit, I opted for a 12-in.-wide sled.

The sled’s body must be flat and rigidI had a sheet of 5-ft.-square, 1⁄2-in.-thickBaltic-birch plywood, so I ripped two 12-in.-wide pieces the full length to create theupper and lower bed sections. If you workalone, resist the temptation to make the sledtoo long and unwieldy. Build it on a flat sur-

face, such as a workbench or outfeed table,to ensure the sled also will be flat.

The frame pieces, 3⁄4 in. thick by 1 in. wide,were cut from a couple of dry 2x4 studs. I re-cessed the pieces 1⁄2 in. on the sides and 3 in.on each end so I could grip the sled easily.The frame pieces are glued and screwed tothe upper and lower bed sections.

The top of the sled has a series of stocksupports made of hardwood milled to 1 in.square. To determine their length, measureyour planer’s inside clearance, keeping in

J O I N T E R S L E D F O R T H E P L A N E R

The body of the sled must berigid, dead flat, and not tooheavy, which makes a torsion-box design the best choice. Therough board that needsflattening rests on a series ofsupports that are adjusted to fitthe board using sliding wedges. WEDGE DETAIL

Cut supportwedges. Asimple jigwith a notchin it allowsRust to band-saw multiple15° wedges.

MAKING THE WEDGES AND SUPPORT BLOCKS

Cut angled slots in the support blocks.Use a sled angled at 15° to cut a slot in theunderside of the support block.

Support blocks,1 in. square

Alternate-facinghooks guide thebungee cord.

Stair-tread materialapplied to top ofsupport blocks andbottom of wedges

Dowel secureseach end of thebungee cord.

1⁄2-in.-thickplywood

Underside issurfaced withplastic laminate.

15°

15° angleddado

3 1⁄4 in.

7⁄8 in.

3⁄4 in.

Wedges

Tighten screw tosecure wedges.

Frame pieces, 3⁄4 in. thick by 1 in.wide, are glued and screwed toboth pieces of plywood.

1⁄2-in. recess for handling

3-in. recess for handling

Bungee cordhelps to securesupport blocks.

mind that the supports will have about 1⁄2 in.of a drywall screw sticking out each end.My planer allowed for 111⁄2-in.-long sup-ports with no danger of a screw headtouching anything on the way through.

In use, the supports are raised or loweredusing 15° wedges made from 1⁄4-in.-thickmedium-density fiberboard (MDF). To keepthe supports parallel to the sled’s surface asthe wedges are inserted, cut a slot 3⁄4 in. fromeach end of the support blocks, also with a

15° slope. This is done on the tablesaw witha dado set, using a sled that carries the sup-port block at a 15° angle. While the dado setis on the saw, cut a square dado in the top ofeach support for a bungee cord. The cordsecures the supports when the sled is in use and when it is stored vertically. I stretchthe cord through the notches in the sup-ports and through small hooks on top of thesled, securing it at each end with a dowel.

60 F I N E W O O D W O R K I N G

To hold the wedges in place, drill a holein each end of the support blocks for a11⁄4-in. drywall screw. Just tightening thescrews by hand keeps the wedges frommoving once they are in position.

When I first built the sled, I had problemswith the planer pulling boards out of posi-tion as the sled went through. To solve that,I put self-stick plastic stair-tread material ontop of the supports. I avoided sandpaperbecause of the likelihood of grit breakingoff and getting in the planer. I also put acoarser stair-tread material on the bottomsof the wedges to keep them from slipping.Last, I put plastic laminate on the bottom ofthe sled to reduce drag through the planer.

Setting up the sled for useLoosen the support screws by hand andslide the wedges back so that the supportsall rest on the sled. Orientation of the boardis important: If the board is cupped, placethe concave side down so that the edgesrest on the supports. Do this regardless ofthe fact that you may now have a boardthat bows up at each end. Space the sup-

ports to have one at each end and two orthree along the rest of the board.

Find the high corners of the board byputting pressure on opposite corners androcking it. Use the wedges to raise the sup-ports that need it, trying to raise each onean equal amount, and tighten the screws byhand. It takes only a little pressure for thefine point of the drywall screw to bite intothe MDF and secure the wedge. Test to seeif the rocking is gone. Now go down thelength of the board and find loose supports.Use the wedges to raise the ones that needadjusting, but avoid coming up too high.Doing so can cause other gaps to appear.

Roller stands at each end of the planerand a removable support arm attached tothe box my planer sits on help support thesled. The arm has a top of heavy plastic(available from Woodcraft) that reduces thefriction of sliding the sled across from theoutfeed end of the planer to the infeed side.

Using the planer as a jointerOnce the board is stable, raise the cutter-head high enough to accept the entire

Place the board on the sled. Ifit is cupped, rest it with the con-cave side facing down. Rock theboard to locate high spots.

Adjust the support blocks.Slide the wedge until the blockjust touches the board. Thentighten the drywall screw byhand to lock the wedge in place.

S L E D S E T U P

Visit our Web site to see Rust demon-strate his planer sled.

finewoodworking.com

J A N U A R Y / F E B R U A R Y 2 0 0 5 61

package and, without turning on the power,slide everything into the planer to find thehighest point. Pull it back out, crank downa bit, and you’re ready to joint the board.This is one of those cases where describ-ing the process takes far more time thandoing it. It’s easy to put a board on thesled, adjust the supports, and be planing in30 to 45 seconds. It helps to know thecombined thickness of the sled and sup-ports so that you can have the planer open-ing set to the approximate thickness.

After the first pass, check to see if any-thing has shifted and adjust the wedges asnecessary. Send the sled over the fixed armand back to the input roller, lower thehead, and make another cut. I recently builta chest of drawers with bent-laminateddrawer fronts and had no trouble using thissled to flatten 11-in.-wide hard maple tomake drawer-front plies. This is a jig (un-like some I’ve attempted) that has provento be worth far more than the original timeinvested in designing and building it. �

Keith Rust lives in Arlington, Texas.

U S I N G T H E S L E DWith the planer turned off,slide the sled through to checkfor obstructions and to deter-mine the highest point on theboard (above). After the firstpass, check and adjust thewedges (left), if necessary.Once you have flattened onesurface of the board (below),you can dispense with thesled and run the other side ofthe board through the planerto thickness it.