Sever Cupping - Any ideas?

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Forum topic by KnowNothing posted 05-30-2016 02:19 PM 537 views 0 times favorited 12 replies Add to Favorites Watch
View KnowNothing's profile


3 posts in 149 days

05-30-2016 02:19 PM

Topic tags/keywords: cupped warped scrap question tip

Hey y’all,
I know nothing about wood. I know I like it and want to work more with it. I found this really cool piece in a scrap pile at my university and decided to take it, it was around 5 inches thick. (no idea what kind of wood it is)

A month later I got it cut in half (~2 inch slabs), it had spent some time drying at a sawmill before it was cut

5 days after it got cut, it started to bow a lot. It might have been just laying like that for those days, but i dont 100% remember

It almost a year later, and these pieces have been in my bedroom against the wall and I assume drying.

So is there anything I can do to fix the wood? I would love to make these two into a table/coffee table. Planning them would only work for one of the pieces because it isnt as bowed/cupped. There would be nothing left of the other piece. In case this is important, I am in Utah, so its kinda dry.

12 replies so far

View jonmakesthings's profile


68 posts in 240 days

#1 posted 05-30-2016 02:29 PM

Other guys may know more and say different but yea….that one piece looks like it’s toast. That’s some serious cupping. If you cut off the maybe 6” or 8” side where it starts to bow back up it’ll give you a new plane to start with and you can save it, but I doubt you could salvage the whole length of the piece.

But I don’t know! Maybe someone here know how to save it :)

-- How can you have any pudding if you don't eat your meat?

View MadMark's profile


970 posts in 875 days

#2 posted 05-30-2016 03:33 PM

It was stored flat, not vertically. It is all end grain so it transpires quickly. The end grain was left unsealed. The warp is most likely set. Try wetting cupped side while on edge and see. Keep it in the shower a few weeks and see if it helps.


-- Madmark -

View Nubsnstubs's profile


811 posts in 1152 days

#3 posted 05-30-2016 03:36 PM

Just break it in the middle, lay it as flat as possible, and fill the crack with epoxy. To make it look a little better when both pieces are glued together, chisel out a continuation of the crack onto the flat piece and fill it with epoxy. Sand and finish your good looking table top.

Just remember, there is never bad wood. There are many ways to salvage what looks like unusable wood.

BTW, that second picture looks like a headless butterfly with a hawk in the middle. .............. Jerry (in Tucson)

-- Jerry (in Tucson)

View stefang's profile


15512 posts in 2756 days

#4 posted 05-30-2016 03:59 PM

Jerry had maybe the best solution, but you could also just cut both pieces in half while removing enough of the center to get two flat pieces, plane or saw the cut edges to 90 deg. and just glue them back together. The disadvantage is that you would then have visible glue joints, but that isn’t always a bad thing.

-- Mike, an American living in Norway.

View CharlesNeil's profile


1602 posts in 3292 days

#5 posted 05-30-2016 04:05 PM


Might take numerous cuts, just a thought

View rhett's profile


734 posts in 3089 days

#6 posted 05-30-2016 04:31 PM

I’ve had good luck with this method.

Take a circular saw and set it to a depth 1/8-3/16 shy of the slabs thickness.

On the bottom, take the saw and make a series of cuts along the apex of the curve, spaced about 1/8-1/4 ” apart. This is much like the method of kerf bending.

This should relieve the stress and bring the board back to “flat”.

Clamp a known straight edge to the front,, flip it back over and then fill the kerfs with epoxy.

This keeps the integrity of the grain pattern on the top and you only see the “fix” on the end grain. A little creativity can make the repair almost invisible.

-- Doubt kills more dreams than failure.

View KnowNothing's profile


3 posts in 149 days

#7 posted 06-02-2016 11:56 PM

Thank you all!

Jerry, I like your idea a lot but will try to preserve the wood as much as I can.

I think so far I’ll kerf the wood. I like that the most so far.

I got a follow up question to y’all: So cupping happens because of inconsistent drying, would that mean that when the wood is “completly” dry it will be flat again?

View MadMark's profile


970 posts in 875 days

#8 posted 06-03-2016 02:27 AM

Theoretically, yes. But it should be rehydrated to a uniform moisture and then dried evenly. Might take a year or two.


-- Madmark -

View KnowNothing's profile


3 posts in 149 days

#9 posted 06-03-2016 05:26 AM

Thanks Mark! I’ll make sure to show what i end up doing.

View Aj2's profile


632 posts in 1220 days

#10 posted 06-03-2016 01:31 PM

Those are weird looking but they look like they would make a nice pair of sandals for a big foot.:)

View BinghamtonEd's profile


2263 posts in 1791 days

#11 posted 06-03-2016 03:03 PM

Just out of curiosity, what would be the proper way to dry two pieces like that?

-- - The mightiest oak in the forest is just a little nut that held its ground.

View HokieKen's profile


1534 posts in 560 days

#12 posted 06-03-2016 07:22 PM

In my limited experience with drying end-grain slabs like that, coat the crap out of it with Anchorseal (or similar), put it in a cool, dark corner and pretend it isn’t there except for to flip it over every few months. Keep ‘em stickered so you get air flow on both sides. Figure a year per inch thickness to dry. Of course you can speed the process up with a makeshift kiln but I’ve never given that a try.

-- Kenny, SW VA, Go Hokies!!!

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