Producing Quarter-Inch Thickness Lumber

Here are several different approaches to the challenge of producing very thin board lumber. January 17, 2011

I'm in need of a lot of 1/4" thick wood. I need it to be 12" wide. Glue up is fine. How would you guys do this? One way would be to slice 1/2" thick boards off the log, dry them, and then plane/sand to 1/4" but I think I'll be getting a lot of warping that way. If I dry narrower boards, and then re-saw the dry stock to a little over 1/4", glue up, plane, and sand would that be better? Or is it too hard to glue up 1/4" thick boards? This has to be solid wood. No plywood.

Forum Responses
(Sawing and Drying Forum)
From contributor M:
What species are you using? What quantity? We used to manufacture 1/4 x 12" glued maple for piano rims. We skip dressed 4/4 stock to 1", ripped to 5 sizes using "glue line" quality blades, edge glued to 12-1/4", re-planed to 7/8", re-saw center , rip to 12", plane to 1/4".

From contributor T:
Starting with 4/4 and ending up with 1/4 like Contributor M describes seems like a lot of waste but I have never manufactured panels at a production level. The thing I want to share is if you try it with 1/2" or 5/8" boards - you need to sticker them no further than 12" apart if not closer and put plenty of weight on them. You may find you need to sticker at 10" or even 8" depending on your species.

I cut thins routinely for the luthier market and also have quite a few DIY veneer woodworkers buying the thins from me. I shave a cant 1/8" to 3/16" (I aim for 1/8" but a big mill is not real accurate for this) at a time and sticker them 6" apart and stack several hundred pounds on them. They dry to EMC pronto. It doesn't take as much time to sticker at 6" as it might sound. You'd think "twice as long" as 12" but it doesn't once you are proficient laying them out.

I know you aren't cutting thins but I wanted to briefly describe how I do it because if you sticker 1/2" ~ boards you need to follow the same process for stickering close and adding weight or they will tend to dry wavy and go nuts on you.

From the original questioner:

I really would prefer doing all the slicing right from the log, rather than going the resaw route. If I slice this wood (maple, cherry, and walnut) right off the log, at 1/2"then sticker it every 10 or 12 inches, let it dry, and then put in the kiln you feel I should be successful without a lot of warping and twisting (as long as I put several hundred pounds on top)? After dry, I'll plan on planing to just a tad over 1/4" with my helical planer, and then finish sand them thru my wide belt. Does that sound like a formula for success?

From contributor H:
All I've ever had cut 1/2'' was walnut and I didn't sticker it. The boards were about 12'' wide and they might of been a 1'4'' gap when the boards dried on the floor. I first put polyurethane after I laid them, and after they dried I just put on a coat of polyurethane to fill the gaps and another coat on the boards.The boards had the round circle marks from the sawmill blade.

From contributor T:
If you have an industrial grade planer your feed rollers will theoretically lay the lumber flat as it goes across the knives/cutters. In reality they will not flatten them 100% but depending on a lot of variables, species/thickness/roller pressure adjustment ad infinitum you can get most of it out as they pass beneath/over the cutters. After they come out the cup is still in the board because the wood flexes back to what the wood fibers tell it to do.

If you use the opposite strategy and cut the wood thicker off the mill in order to plane the cup out of the board, you have to have very little roller pressure in the planer so that the cupped board will not be flattened very much by the rollers and the knives can take the cup out. Obviously always send the board through with the cup up using this technique.

From contributor A:
I saw 7/8 and dry on 12 inch spacing. Then resaw into 3/8 thick boards then plane to 1/4. Thin boards will cup some due to moisture in the room but will lay flat when used. I have dried SYP up to 18 inches wide and then split them for thin stock. Scroll sawers really like wide walnut about 1/4 thick.