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I have a beautiful set of Bocote that I've been attempting to stabilize for over 2 months now. It seems to have a stubborn memory.... Sides are great...but I can't get the backs to flatten out. I've tried soaking them and stickering with weight/clamps etc.... and tried misting and putting on concrete with weights for a slower drying process... and each time after a couple weeks...take them out and within 2 hrs. are back to a 1/8-3/16 cup. It isn't thick enough to mill flat....so I need to retrain this stuff to be flat.

Plans are to again soak and attempt to sticker (not flat) with shims reversing the natural cupping in the opposite direction slightly and see how that goes.

Any other luthier tricks to save this set from becoming headplates, rosettes and end pieces.

Kent

Happy Thanksgiving to all.

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Wood Creations by Kent A. Bailey
EXCELLENCE IN SCULPTURE, CARVING, LUTHIER, ARCHITECTURAL MILLWORK AND DESIGN

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Kent,

Treat them like sides. Heat them up and bend them into submission. Don't forget the spring back.

Steve

I use a household iron to flatten warped back plates, damp wood, damp rag on top, and iron it out and sticker flat. It also helps if you tame the plates enough, to thin them out a bit in the thickness sander before they have a chance to wake up to what is going on.

Cheers

Kim

I've used a household flat Iron to flatten wood and steam out dents or digs. Amazing what an otherwise useless tool can do.

Jay

Actually, they also come in handy for waxing skis. But other than that, I do agree completely!

Unfortunately, my employer would NOT agree!

i don't think I would use the water , but the iron may help. It often can take care of itself with the bracing. I have used the hot iron technique many times. If you can hold the shape with 5 lbs the bracing will most likely hold the shape once glued on a guitar. I will make most backs .100 on less. Bracing of 3/8 by 3/4 will be plenty stiff and should hold the radius. 1/4 bracing on the waist and upper will also help.

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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

Wood is stiff a nails....and has a stubborn memory. 5lbs pressure barely touches the cupping. I will sneak off to the closet for the iron and see what progress I can make with this heat method.
There's not enough thickness to attempt a couple passes through the sander.

I have some 3/4 angle Iron I could use for bracing.....if it come to that.

Thanks guys.
Kent

_________________
Wood Creations by Kent A. Bailey
EXCELLENCE IN SCULPTURE, CARVING, LUTHIER, ARCHITECTURAL MILLWORK AND DESIGN

http://www.kabart.com

I think that as long as it is not turned into a real potato chip, and otherwise nice and stale, it can be happily used. I would wait for it to settle back a bit after all those stresses, then join and thin with a plane. Plane according to the cupping, thinning only the spots that stick out, the belly on one side and then the corners when flipping. This doesn't reduce the cupping by more than a few percents but it is still better than nothing. I would also make the back thinner than usual, 2mm max if a dense wood, and beef the bracing, switching from 3 to 4 braces, and perhaps increase the brace width too if a large guitar. The thinner it is the less it fights back at you and the more bracing, the better it is kept under control - simple logic. Perhaps a good opportunity for trying one of those x bracing varieties.

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