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Hello,

I'm in the process of building a new Zebrawood guitar, 00 sized. I'm having some issues with the sides. I bought and resawed the sides and took them down to 2.2mm thickness using a drum sander. I've bent several sets of sides from other wood species and haven't had a problem. Unfortunately with the Zebrawood I'm getting some cracking in the upper bout and some cupping in the upper and lower.

I read several posts on here about only spritzing or even dry bending. I tried a few test pieces and even they did the same, cracked and cupped.

I'm using an LMI bender with a silicone blanket. I'm setting the heat to 150c. I'm bending the waist to about 25%, then the lower then upper bout and lastly completing the waist. I've tried also soaking the side for 10 minutes and then wrapping in aluminum foil. Steam was rolling out the ends of the foil while bending. Same results.

I'm wondering if there is something critical I'm missing or should be doing differently. My entire bending process from plugging in the bender to completion is around 12 minutes.

Any ideas are appreciated. Thanks!

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This sounds like a job for Super-soft

Although ZW tends to ripple because of the ribbon figure it bends very easily -- if you are have problems my bet is that your material it too thick -- .078" or a little less is good, over .080" can be bad news.

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Ken Cierp

http://www.kennethmichaelguitars.com/

First test piece was taken down a little below your recommendations just to test, I bent it at 0.70 without issue. I'll bump it up on the test pieces to make sure the process is good before bending the real sides. Thanks for the tip!

Is there a recommended thickness based on species chart around? Something like the temp chart that folks have put together?

Thanks again!

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Sure would like to see a photo!

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Here are the test sides in the form. They were only 24" long but let me test the bends at the waist and upper bout and most of the lower bout. There was a fair amount of spring back, maybe because I was yanking them out of the bender after 30 minutes and slapping them in the form. The left was thicknessed to 0.078 and the right was ~0.079


Here you can (hopefully) see the cupping on the failed bend. This side was at 2.2mm.


Here is the crack in the lower bout of a failed bend. Again, this side was at 2.2mm.


Thanks for the help, folks! After 3 successful test bends I'm more confident the real deal will go well. Wish me luck!

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Thanks Brad,
Really like the look of the Zebra wood!
I hope you get the bending figured out.
Dan

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The sides bent successfully. A very small amount of cupping right out of the bender but it seems to be relaxing some this morning. I'm not sure if that is expected and if it will eventually work itself out.

Here's a couple of pics.

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