Warped Rosewood

[John Reid]

I just got some Indian Rosewood that quickly warped as shown in the picture. Trying to figure out what to do.

In the dead of winter, I struggle to keep the humidity in my shop above 30%.

I looked around a bit in the forum and also found a nice YouTube from StewMac about this. I’m hoping to get some input now as well.

One thing I tried was placing the pieces in a box for a couple days where I got the humidity up to 70%. This did absolutely nothing to the shape.

The StewMac video shows a similarly warped piece and they simply force it flat to glue the pieces together. So, I guess I can do that. But how do I go about thicknessing them? The pieces are 0.150” thick now. I don’t have a sanding planer. What I have been doing for thickness pieces is planing. Don’t know how a small block plane will deal with the curves. Should I just go at them with sandpaper on a block or an orbital sander?

Any thoughts and suggestions are most welcome!

[Kevin Sjostrand]

Yikes John. Potato chips!

I've had that with some walnut in the past.

I suggest this:

Clamp them flat (easier said then done right) so you have access to the gluing edge and plane the edges best you can. Then I'd force them flat again on some nice flat 3/4 MDF using some wide strips of double sided tape at the same time gluing the plates together. IF they stay down flat, then you can hand plane and sand to dimension.
If your joint isn't perfect you can route in for a decorative center strip while they are still forced flat.

When you glue on back braces it will probably conform and work out okay.

I think what I did with the walnut was soak them, and then weighted them down flat and left them to totally dry.
I remember they were not perfect but much improved. That was many years ago.
Good luck how ever you move forward.

[John Reid]

Thanks Kevin,

I was worried about clamping them flat and causing a split. I hadn’t thought of soaking them first. Hopefully I can get them a bit more flat so planing will be manageable. I figure thinning them will help the bracing to shape them.

[Stray Feathers]

Is it worth asking the supplier? Maybe they would rather replace the wood and have a happy customer? I've never seen wood like that from a supplier, and my shop is always between 30 and 40% in winter, sometimes as low as 30%. Or maybe they would thickness sand it for you? Bruce W.

[John Reid]

I’m pretty new to this. I don’t know how normal/common it is for such wood to warp. So, you think it might be worth and inquiry to the supplier?

[Kevin Sjostrand]

John
Was the set flat when you received it?

[John Reid]

Yes, it was perfectly flat.

[Kevin Sjostrand]

Might be difficult to return it??

[Stray Feathers]

You raise a good point Kevin. I am no expert but it looks like either the environment in John's shop caused the warping, or perhaps the wood was shipped when not properly dry - hard to prove. It might still be wise to send them an email and photo and explain what has happened, just so they know about it, not to blame them ("I am a new builder; should this be happening?") You could ask if they have any tips to correct it, i.e. you are prepared to try to use it if you can. The supplier might still offer to take it back, or might offer advice. If you end up trying to use it, I'd follow Kevin's suggestions. And when you get them flat and dry, immediately shoot the mating edges and glue them, and then you can clamp or weight the glued plate if need be until you can work on it. But it would be really good if you could find someone to thickness sand it for you quickly while it is flat. I don't know if the heat from sanding would cause more warping. I am curious - did you get sides too, and did they warp also? And do you know anyone with a wood moisture meter you could borrow to check the back and side pieces? Bruce W.

[tippie53]

get an iron and iron them flat , and keep flipping and ironing
then clamp flat this was wet and it will always cup up when dry and down when wet