Removing "twist" from an end-grain cutting board?

[Marty Tippin]

I've made quite a few end-grain cutting boards, but ran into a problem on my most recent one that I'm not sure how to fix. After my final glue up and running it through the planer to clean up both sides, I find that there's a bit of twist - maybe 1/16" to 3/32" where one corner is high (i.e., if I were to put rubber feet on it now, one of the 4 feet wouldn't touch). I've checked all 4 corners and they're the same thickness, so I don't think it's an issue with how it went through the planer.

So I'm looking for ideas on how I might be able to get rid of the twist or hide it in the finished product.

I've considered running it through the planer again with a shim under the high corner, which *should* produce a flat surface on the top, then flip it and run through a second time to bring the second side parallel to the first. Not sure if that would work or how I'd shim it. I could also try using the drum sander with a shim to produce the same result, but it takes just short of forever to sand any significant amount of end grain.

The board is about 14"x20" so I can't (and wouldn't if I could) run it over the 8" jointer.

I might be able to shim one of the rubber feet (or trim the other 3) enough to get them to sit squarely but that feels like a lot of work.

Any other suggestions?

[John Schweikert]

What about setting the rubber feet to compensate. I've done that for a board which was left with more of live edge style and not completely flat. The rubber feet were recessed as needed depth wise. Not too hard.

Otherwise, if you have access to a drum sander, then run it through with a planer sled style board underneath to shim. Once the one face is sanded then run the other through. A well tuned drum sander can work great as a thicknesser. The sled will aid in the initial twist.

[Matt Radtke]

Low angle jack plane. Get the twist handled on one face and get the opposite parallel however you normally do it.

[Marty Tippin]

if you have access to a drum sander, then run it through with a planer sled style board underneath to shim. Once the one face is sanded then run the other through. A well tuned drum sander can work great as a thicknesser. The sled will aid in the initial twist.

I whipped up a sled from the flattest piece of plywood I could find. Double-stick tape and a veneer shim under one corner of the cutting board, and a dozen passes through the drum sander and it's close enough to flat for me...

Thanks for the suggestion - I really didn't expect to be able to take off enough material with the sander but it went quicker than I thought it would.

I could have tried the same trick using the planet except I had already cut off the sacrificial strip that I use to prevent tear-out at the back of the board and it would have been a hassle to re-glue a piece...

[Doug Garson]

Glad you were able to resolve the twist problem safely but before you consider using your thickness planer again I suggest you Google " running end grain cutting board thru thickness planer" and look at the results.

[Marty Tippin]

Glad you were able to resolve the twist problem safely but before you consider using your thickness planer again I suggest you Google " running end grain cutting board thru thickness planer" and look at the results.

Thanks but I run end grain cutting boards through my planer all the time without issue. It just requires care and very light cuts.

[Doug Garson]

OK I haven't tried it myself for the reasons given in the search results. I assume you understand the risks so if you're able to due it without issues then so be it.

[John K Jordan]

I have seen a router used for this, for flattening large slabs but it should work very well for cutting boards. Basically you make two rails that are straight and flat on top and fasten them securely to a workbench or frame, aligned with winding sticks. Then make a simple sliding jig from two pieces that reach across the rail, with a gap between. A router rests and slides on the top of the jig. Slide the jig down the rails while moving the router back and forth on the jig, cutting through the gap. This will flatten anything on one side, even a stump.

[eugene thomas]

Just cures what drum sander you have marty. I use to have woodmaster and if made endgrain cutting board would use the sander for all end grain work..

[Marty Tippin]

Just cures what drum sander you have marty. I use to have woodmaster and if made endgrain cutting board would use the sander for all end grain work..

I've got an older Performax 16-32. I normally use it on end grain cutting boards to clean up the surface after passing through the planer; never tried it for thicknessing before. It worked surprisingly well but I won't be using it for that purpose regularly. Would really like to have a dual-drum sander so I could use two grits at once and have less ROS work, but it's not in the cards...

[John K Jordan]

dual-drum sander

That would be so nice! When I worked at the Berea College woodworking in the 60's they had a huge triple drum sander. It was amazing. Put a glued up chess board in one end and come out so smooth in one pass. I remember it was a big job to change the sandpaper...

I use a 22-44 and get a lot of use out of it, even for (relatively thick) veneer for woodturning glueups.

JKJ

[john bateman]

A while back I made a board and was very careful to get it flat. Then I put it on the countertop where it would reside, and it rocked. Moving the board around the counter, it was obvious some parts of the counter were flat, while others weren't. I told the wife to just use it for awhile in the place she preferred to cut things. After about 2 weeks, the board had conformed to the less than flat counter, and no longer wobbled. FWIW, I used cork discs for "feet", about 1/4" thick and 1-1/4" diameter.

[Erik Christensen]

i tried a number of ways to flatten my end-grain boards - router sled, hand planes, etc. for the tools at my disposal the fastest & best results was a 4x24 belt sander with 36 grit and a pair of winding sticks