Side Bending

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Tunesmith
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Joined: Mon Dec 12, 2016 12:40 am

Side Bending

Post by Tunesmith »

If you properly bend a side (getting it to a high enough temperature to 'set the bend'), should spraying the side with water cause it to lose the bend?
tippie53
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Location: Hegins, Pa
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Re: Side Bending

Post by tippie53 »

it may much depends on the wood and how much water. for the most part it should stay bent. Spraying any wood with water can make the surface cells swell.
John Hall
Blues Creek Guitars Inc
Authorized CF Martin Repair Center
president of Association of Stringed Instrument Artisans
http://www.bluescreekguitars.com
Tunesmith
Posts: 2
Joined: Mon Dec 12, 2016 12:40 am

Re: Side Bending

Post by Tunesmith »

John, thanks for the quick response! I'm new at building acoustics, so I wanted to do some test runs on my Fox-style side bender, using some Maple sides. After I bent the sides (following your instructions in your side bending video tutorial), I thought that I had not gotten them hot enough to 'set the bend' (I was using a poor method to monitor the temperature), so I re-sprayed the sides with distilled water in preparation for another round in the bender. But after I sprayed the sides, within a minute or so they began to relax and lose the bend. Then I re-bent the sides by getting the temperature up to 350F, then setting it to 250F for 15 minutes, then cooled down to room temperature. I also ran some Maple scraps through the bender using the same technique (so I could test the bend set). I removed the scraps, sprayed them with water and they immediately lost the bend and flattened out. Is my technique wrong?
JLT
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Joined: Wed Nov 02, 2011 9:13 pm
Location: Sacramento, CA USA

Re: Side Bending

Post by JLT »

tippie53 wrote:it may much depends on the wood and how much water. for the most part it should stay bent. Spraying any wood with water can make the surface cells swell.
I agree. I usually bend the wood at least semi-wet ... spray it with water before I bend it, counting on the steam to help melt the lignum. When all the bends look right, I put the side into the mold and secure it there, so that the wood dries out in the pre-set bend condition. This works with rosewood, walnut, and maple, but I haven't tried bending other woods (at least, not for sides).
tippie53
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Joined: Fri Mar 03, 2006 7:09 pm
Location: Hegins, Pa
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Re: Side Bending

Post by tippie53 »

maple likes less water and more heat so a light spray take the heat up to 350 for 2 min let set at 250 and repeat.
what is the thickness of the side?
also you don't need to spray them once you pull them out of the machine . Also get them in the mold asap
John Hall
Blues Creek Guitars Inc
Authorized CF Martin Repair Center
president of Association of Stringed Instrument Artisans
http://www.bluescreekguitars.com
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