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I've got a walnut set and a padauk set that have been sitting in my humidity-controlled basement but they are developing some warp. I plan to use these in the near future so I was wondering what you guys generally do to flatten your back sets. Thanks -Alex

Most time the braces will take that out.
If it is real bad you can heat it up with a cloths iron before gluing on the braces.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

This is the response I got from Bob at RC Tone Woods about a set I have that is cupping. I have not tried it yet.

"you can wet the concave side of the backs. Then stack with the 2 wet faces facing each other and place a board and weight on them. Leave like that for a few weeks. Then place stickers between the pieces and weight down for a few more weeks. The longer the better. This happens when kiln drying too quickly. The outside faces of the board are drier than the inside. Hope this helps."

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EddieLee

If you happen to have access to a large dry mount press, they can work well too.

Pat

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formerly known around here as burbank
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http://www.patfosterguitars.com

I use a regular clothes iron with parchment paper between it and the wood to keep the funk off the iron.. One tip is to cut the outline fairly close to shape on each half before flattening, this allows the wood to be less constrained and it seems to flattens easier..

Peter

the thing i did for a severely twisted set of madrose - after the advice from Alex Marian - was cutting it to near final shape, wetting the concave zones, facing them against each other the best i could and then stash a couple of packing grade spruce boards against each of the outer faces of the rosewood, wrap it up in plastic, placed a 1 inch board and some weight (around 30 kgs, IIRC) and let it sit for a couple of weeks. it apparently did the trick.

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Do not heat if there is any wax on it. The wax will flow into the wood and compromise glue joints long into the future.

I have set of BRW 1/4" thick that was warped and would not flatten under weight. It did not change with three days soaking in water. After a week im water, it straightened out dead flat. I stickered and weighted it to dry and it remained flat after it dried, and I keep it stickered and weighted until I may use it.