surfacing thin pieces?

[Charlie Self]

mel asks:

The sled is much longer. You can actually make it any length you want, but with most tables under 2' in length, I wouldn't bother with a sled under 6' long.

Obviously, as above, the upward pressure on the last few inches of the piece are going to be less, so there's less chance of snipe.

A sled does limit the capacity of the planer, but by a whole 3/4". When was the last time you actually used the 6" capacity of your planer.

The sled material won't lift into the knives because the material being planed is on top of it, holding it in position. There is also a cleat to keep it from sliding through. On exceptionally long sleds, the cleat can be made to overlap the underside of the infeed table so that it can't rise after the material being planed goes through.

Charlie Self "All you need in this life is ignorance and confidence, and then success is sure." Mark Twain

[Joe Willmann]

"mel" wrote in news:FAyTb.397$ [e-mail]:

It gives you something to attach the thin material to. What I use is a spray 3M adhesive. Spay a light coat on the sled. Spary a light coat on the thin veneer. Put the veneer on the sled. Now you can run the sled throgh the planer without the thin veneer causing problems. Use a light tack glue and the veneer will peel off. Then wipe it down with the correct solvent for the glue and you are good to go.

Disclaimer. I only needed to do this once. I needed some 1/16 inch balsa. I had some 1/8th and the hobby shop was closed. It worked great.

[A Dubya]

Hey Mel,

It ultimately, eliminates the flex in your material. This is especialy significant, in thin stock. Your rollers on your planer table might be a few of thou above the table itself. As the knives come in contact with your stock, the stock is thin enough to flex slightly, your more likely to get tearout, etc,etc. The rollers usually do not present a problem in thicker stock (the stock won't flex).

Carriage/sled, potato, patato, all you need is something to give you a reliable/repeatable process. "A jig for planing thin stock".

The longer the better, but even a few feet will do, especially if you don't plan on using it very often, and your tolerances aren't exceptional.

Cheers,

Andy

[jev]

I don't believe adding an auxiliary table e.g., melamine covered board, can guarantee great accuracy across its face

Many of us are working with 13" variety portable planers where the knives are not adjustable. In addition, I don't believe the parallelism of knives to feed table is guaranteed within a thou or so.

The carrier board should just be run close to same position each time.

I assumed that one face had been jointed.

Actually, I use this procedure for laminations where I may have to laminate 20 or 30 slats of 1/16 each. If each is off parallel by say

2 thou then over 30 pieces the opposing faces are out of paralle by 60/1000 or roughly 1/16" !!

[A Dubya]

Hey Jev,

I stand corrected, non adjustable planer knives are more of a challenge.

I'm fortunate enough to have 16" wide to play with. If need be, I can dial my knives to a thou across the 16" in less than 5 min (on the table, or a carriage).

Cheers,

Andy

[CW]

I wouldn't worry about compression. I've taped aluminum blocks to milling machine tables to surface them. Will get it within a .0001 or so every time. Use the paper or Mylar based tape, not the cloth carpet tape.