Warped Board

[NYHump]

Hi All,

I have a problem. I have a piece of Cocobolo 1/2 thick that is wraped. I need some ideas on how to get it flat without losing the 1/2 thickness. The board is roughly 10" x 18" x 1/2"

Help, I need to save this beauty. The piece is book matched 2 5" pieces wide gluded up

Thanks,

NYHump

[Larry Marshall]

If you have thoughts of somehow straightening the board by twisting/clamping it, put those ideas out of your mind. It won't happen.

You didn't say how the board is warped. If it's cupped, you can often rip it in half, flatten the two sides, and glue up the results. If it's warped end-to-end, using it in a project where you need shorter boards might be a solution. If it's twisted, how much thickness you'd lose by flattening it depends upon how you do the flattening. Machines will remove a lot of stock but you can sometimes save quite a bit by strategically using handplanes to flatten it.

I suspect these aren't the answers you're after but they're the ones I know.

Cheers --- Larry

[Frank Speyerer]

Larry, since the board is only 1/2" thick, I was going to suggest soaking the board to make it more pliable then clamping it to reverse the warp. But, from what you said, this won't work?

[SawDuster]

I have a piece of Cocobolo 1/2 thick that is warped ...

Hi NYHump,

Is this board bowed, twisted, cupped, or a combination of these? Depending on the nature of the deformation, there 'may' be a way to make this board usable again without cutting it in to smaller pieces.

I agree with Larry Marshall about twisting/clamping - that's likely wasted effort. You must find a way to relieve the internal pressures that are causing it to deform.

[Larry Marshall]

Larry, since the board is only 1/2" thick, I was going to suggest soaking the board to make it more pliable then clamping it to reverse the warp. But, from what you said, this won't work?

Only one old guy's opinion but I don't think this will have the desired effect. The wood warped, most likely, as its moisture content equilibrated with shop conditions (presuming it wasn't warped when purchased). Thus, you can soak it til it won't float but the warp will return when it dries out.

Cheers --- Larry "aka Woodnbits"

http://www.woodnbits.com/blog

[Timberwerks]

Hi All,

I have a problem. I have a piece of Cocobolo 1/2 thick that is wraped. I need some ideas on how to get it flat without losing the 1/2 thickness. The board is roughly 10" x 18" x 1/2"

Help, I need to save this beauty. The piece is book matched 2 5" pieces wide gluded up

Thanks,

NYHump

The only thing I can think of will leave you with one side suitable for show. You make multiple kerf cuts on the non show side about 2/3 total thickness. Dampen face side and clamp flat, fill kerfs with epoxy. I have done this myself, it does work great but you are left with one show side.

[DeanJackson]

Only one old guy's opinion but I don't think this will have the desired effect. The wood warped, most likely, as its moisture content equilibrated with shop conditions (presuming it wasn't warped when purchased). Thus, you can soak it til it won't float but the warp will return when it dries out.

Cheers --- Larry "aka Woodnbits"

http://www.woodnbits.com/blog

If whatever you're going to use if for only has one side for show, you could wet it, clamp and force it straight, and then reinforce it, either with battens or another piece of wood behind it.

There's also a possiblity of planing it flat, less than 1/2" thickness, then using it as veneer, right?

[PaulMarcel]

The only thing I can think of will leave you with one side suitable for show. You make multiple kerf cuts on the non show side about 2/3 total thickness. Dampen face side and clamp flat, fill kerfs with epoxy. I have done this myself, it does work great but you are left with one show side.

haha, I did exactly that on a project awhile ago, except I used Bondo as the filler (sands very nicely, btw). I kept telling myself "okay, don't tell anybody, hide the Bondo, they'll never know". Can't deny it worked great!

[NYHump]

The only thing I can think of will leave you with one side suitable for show. You make multiple kerf cuts on the non show side about 2/3 total thickness. Dampen face side and clamp flat, fill kerfs with epoxy. I have done this myself, it does work great but you are left with one show side.

Thanks DJO, I think this will work since only one side shows. Also, both sides are really nice so it doesn't matter to me which side I chose to be the good side. The board is cupped and a little twisted, which side would be better to cut the kerfs the convex or the concave. I'll have to pick up some epoxy, any suggestions on what to buy for this?

[Timberwerks]

Thanks DJO, I think this will work since only one side shows. Also, both sides are really nice so it doesn't matter to me which side I chose to be the good side. The board is cupped and a little twisted, which side would be better to cut the kerfs the convex or the concave. I'll have to pick up some epoxy, any suggestions on what to buy for this?

Any good brand 60 minute will do. Kerf the least attractive side, that would be first choice. If both sides are the same looks wise I would kerf the concave side.

[klousiajp@gmail.com]

Any good brand 60 minute will do. Kerf the least attractive side, that would be first choice. If both sides are the same looks wise I would kerf the concave side.

Interesting, why the concave side? I would have thought the exact opposite.

[SawDuster]

Interesting, why the concave side? I would have thought the exact opposite.

Well let's think about that for a second. If you cut kerfs in the convex side, when you turn it over and clamp it flat your kerfs will close, making it difficult to apply epoxy. By cutting kerfs in the concave side, just the opposite will happen - which doesn't matter - they'll be filled with epoxy anyway.

It is likely the concave side caused the cup in the first place. You can verify this by looking at the end grain. The outer growth rings will likely be on the concave side of the board if it was flat sawn.

Good luck and keep us informed.

[Timberwerks]

Hi Len

You got the idea, getting the kerfs to open. I also do it this way because you can fill the kerfs with wood strips as well. If you fill the kerfs with wood strips it could add visual interest if you opt to also show the correction side. Strips died black wouldn't look to bad against the Cocobolo. Brass strips could also be a possibility. It really all depends on the project. If the cup is severe I would kerf every 1/4". It's really a simple trick actually, I tried it after looking at bendable plywood used in veneering curved pieces.

[NYHump]

Any good brand 60 minute will do. Kerf the least attractive side, that would be first choice. If both sides are the same looks wise I would kerf the concave side.

DJO,

I'm kinda new at this so please be a little more speific on the filler. 60 minute? I feel so clueless but I guess this is where you can educate me on stuff like this. If you can give me a brand that you have used that gave you good results for this. Also, how would you cut the kerfs in, I'm thinking a circular saw set to depth.

Thanks again,

NYHump

[PaulMarcel]

Just means an epoxy that will set in 60 minutes. You wouldn't want to try filling those kerfs with 5-minute epoxy... it would be a rock before you got far enough along.

I think the Bondo would be much easier; it spreads very nicely. If you want a little more working time than the 20 minutes (or so) before it gets hard, pop it in the fridge to cool it down before you mix and start. I have to do that here (Arizona) or it, and any epoxy, sets right away. (So, yes, the West System epoxy is right next to Kilt Lifter and Coronas; don't get them mixed up ).

With epoxy, you'd really want a filler in it to thicken it up anyway. For West System epoxy, the 404 filler would work well. Otherwise, you're using a ton of epoxy. Bondo is essentially epoxy with filler.

[Timberwerks]

DJO,

I'm kinda new at this so please be a little more speific on the filler. 60 minute? I feel so clueless but I guess this is where you can educate me on stuff like this. If you can give me a brand that you have used that gave you good results for this. Also, how would you cut the kerfs in, I'm thinking a circular saw set to depth.

Thanks again,

NYHump

Yes, a circular saw for cutting the kerfs or a router and an edge guide. I agree with what Paul said about epoxy and bondo. The reason I use epoxy is for the color.

[PaulMarcel]

ooh, sorry... didn't see part deux of the question. Good point, I was assuming the kerf side was going to be completely hidden. Though I liked the other idea presented earlier of using brass bar.