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About 1 week ago I received two sets of indian rw, 2.5mm thickness.

Both sides and 1 back set look just fine, but the other back halves twisted a bit. It happened during the first day after they arrived. My storage room is always between 40 and 50%, 19-20 C.

If I put a plate on a flat surface, the upper right and lower left corners point up, the other two point down. They also can be flipped in hand to point the other way, sort of like a Rubik cube, and they stay like that.

I was going to let this set acclimatize about 2 months before joining and using it, but I am under the impression it's not going to straighten up by itself.

I assume this type of twist happened to some of you. What did you do?

I was thinking about removing the lateral excess as in cuttin them to shape plus 1 cm, and clamp them straight...

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Build log

Alex, one solution I have used for distorted boards is to put a sticker between and oversize stickers on the outside and then clamp them together using cable ties, like this. Damp, the concave areas.



Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Thanks Colin (nice MadRose there, hope it fixes nicely)

After I clamped the stickers it was still twisted and twisting in the hand so I clamped the whole stack to a piece of flat marble.

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Build log

Yes Alex it straightened out in no time and has been stable now for a couple of years. Hope yours goes OK.

The usual trick with cupped plates is to put them, cupped side down, on a concrete floor and often overnight they will have flatted.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

I am toying with cupping spruce. I like to think I am helping them age/dry better:

The next 4 spruce halves i will be using are laid on the sofa in my storage room. After about 12 h they cup a little so i am just flipping them over. 12h later they are flat again, then they cup again I flip and so on. At least in theory it seems they would shrink from classical size to uke size in the next couple of months

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Build log

I 'bend' backs and sides flat if need be ... simply wrap and spritz the wood, then onto the table saw top with the heat blanket and some wood and weights on top, then set the heat and wait 15 minutes ... then let cool .. works all the time. I have done this with braz, coco, eirw and mad rw but am pretty sure it will work with anything.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

I've used an old steam iron to literally iron them flat and then clamp flat until dry.

The old dry mount press from my photography days works really well.

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now known around here as Pat Foster
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http://www.patfosterguitars.com

I have never found a need to iron a set to flat. Cupping and warping is most always cause for difference in the environment form where they have traveled from and to. If racked or warped but will flex flat with out causing damage, I first just sticker them for a month or more and let nature take care of them. If minor cupping I do the same but if they persist I place them cup side down on the concrete floor and in a day or two they are flat. Then into the sticker they go.

Michael, the stuff was in European surface mail for nearly 2 weeks, must have sucked in some moisture. But the rest of the stuff, add some binding planks, spruce and cypress bars, and, low grade spruce tops used for packing did not move.
Anyway,
Thanks for all the suggestions!

I will keep it clamped straight for about 1 month, see what happens and if no luck I'll put it to the toaster.

We need a pyromaniac smiley.

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Build log

Did I see a request for Flamed Rosewood? Oh yeah, Flamed Redwood. Not the same.

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Waddy

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