Number of Supports for 4-Foot Planing Sled?

[Steve H Graham]

I have no jointer, so I made a planing sled for my planer. The sled is four feet long. Following Keith Rust's design, I used one support per foot of total length, or four supports. I have seen people on the web suggesting that this may not be enough. Can someone tell me how many supports I need, or, more generally, what the best distance between supports should be?

Guess I'll upload a photo. I haven't added the hooks, stair tread material, or bungee yet.

[Mike Cutler]

Nice sled Steve!

I don't think there is a hard and fast rule on the number of supports. I would put as many as you can.

The thickness and the density of an individual board, along with how much material you're trying to remove in a single pass, will have a lot to do with how much support it need to resist the force of the feed rollers. A 4/4 pine board would need more support than a 8/4 board of maple for example.

I think that I personally would put in additional supports between the 4 you already have, a total of 7, then stick a pine board on it and see if it washboard between supports, If not you're good.
Who knows? maybe 4 is already enough. Try it.

[John Schreiber]

Be sure to show us pictures and let us know how it works for you. I tried something similar using wedges and screws and tape to hold the wood in place, but I found it easier to use a hand plane.

[Matt Benton]

I just used screws for supports...

[Anthony Whitesell]

Same here. My sled is 4' long and 12" wide made 3/4" MDF sheet with 2 2" wide 1/2" runners and 1/4" threaded inserts on 6" centers down the length and varying 1-4" apart acress the width to account for various width stocks. Just remember to have a support at the very leading and trailing ends.

[Rob Diz]

I have had good luck just using shims, even on 4/4 walnut and cherry.

I have used my basic sled - mdf with a lip on the leading edge to keep the stock on the board - to face joint a large number of boards wider than my jointer. I recently face jointed a significant number of wide boards, some almost 5 feet long using shims, and the boards turned out straight.

I spent a few minutes with a hand plane to knock down the high points, but overall I have yet to find the need to make a dedicated planer sled. I use the mdf for these sleds for jigs etc, and when I need more mdf, I'll stop by the BORG and get a discount on their damaged sheets. I have a small shop and just keep jigs around that aren't really needed.

Just my .02.

[glenn bradley]

I also followed the Rust design (http://www.sawmillcreek.org/showthread.php?t=58735) which has 5 spread across a little over 4' of length. The remaining few inches on each end hold the dowel and bungee. I often left one cleat off (http://www.sawmillcreek.org/attachment.php?attachmentid=65391&d=1180368402) unless doing a full 5' piece of material.

This sled carried me for about a year and a half while I saved up for an 8" jointer. I still use it for extra wide stock. It replaced the piece of MDF with a stop and a bed of screws which worked fine but was a bit of a pain to setup on thinner stock. The sled only took a day to make, is much faster to set up but heavier. HTH.

[Steve H Graham]

Someone asked me to stick a board on this thing and report on my results. I plan to do that, but this will be the first time I've run a planer, so you can't really judge the sled based on things like whether the planer explodes or I electrocute myself.

[John Schreiber]

. . .this will be the first time I've run a planer . . .
Make sure you've got ear protection. Mine's so loud I can't really think with it on, unless I've got ear muffs on.

[Alan DuBoff]

I have been wanting to build one of these for a while, and just mentioned it in another thread, which somehow was mis-interpreted by the OP...but your sled looks great!

How is the bottom of the sled constructed? I'll have to search and see if Keith Rust's design is somewhere online.

[Russ Sears]

Alan: it's here (http://www.taunton.com/finewoodworking/SkillsAndTechniques/SkillsAndTechniquesArticle.aspx?id=5245).

[Steve H Graham]

I didn't do exactly what Rust did, because I had no jointer to face joint the inner bits of wood, and I had MDF lying around instead of plywood. The top and bottom are the same. Both are 1/2" MDF. I was considering spraying dry lube all over the bottom to make it slide on the planer ramps, but then it occurred to me that if it didn't work, I would have a hard time applying a sheet of laminate to it for the same purpose. The lube might keep it from adhering.

[Jules Dominguez]

The sled works as claimed in the FWW article in which it was presented. I made one 13" wide and to handle up to a 54" long board. It has six supports. I don't use all of them for shorter boards. Don't sweat it. Make as many as you think you might need and use as many as you think you actually need for any given board.

All of my stock is rough white oak and cherry - some of it twisted, cupped, bowed , warped and/or dog-legged, and occasionally one or more of the sled supports can't be raised high enough with it's wedge to support the board. When that occurs, which isn't often, I use an extra (typically very thin) wedge between the top of the support and the workpiece.

The sled plus workpiece is of course heavier than the workpiece alone and you do have to horse it from the outfeed end of the planer back to the infeed for multiple passes, but that shouldn't be an issue for most folks.

Except for boards which are very straight in the rough, I usually break the rough stock down to somewhere near finished size before starting to flatten it.

My rough stock is about 1 1/8" and I can get it flat and straight with most boards around 7/8", some a little over 1" and some I have to take all the way down to 3/4".

I also use a sled to get the first edge straight on the tablesaw, but that's another subject.

To flatten very short pieces - up to about 18 or so inches I use a simple sled of 1/2" MDF with a cleat on the lead end, and wedges to support the workpiece where needed. I keep a tin can full of wedges of various sizes.

I don't have a jointer, and I use handplanes and/or the sleds as part of the prep for all of my wood. It's slow at times, but I'm not in a hurry.