Official Luthiers Forum!

I'm about to start #6. I would like to try a Venetian cutaway on this one (plus a bound fretboard). I'm
using a medium priced set of Koa, not real high figure. I normally use blanket machine from Blues Creek, but
I'll probably do the cutaway on my hand bender. How tough is Koa to bend? The guitar will be Martin
OM size. Also, how thick should I make the sides. I normally use .085-.090". Should I thin the cutaway
area more than that?

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Gene

Politicians and diapers must be changed often, and for the same reason- Mark Twain

koa isn't that bad to bend. On highly figured sets I use wet paper to layer under and over the wood. I use a temp of 325 for this. Be sure to let the wood cool and dry. once you have it cycled open the lower bout and take out the papers. then reset the holdowns and do the upper . Once you get most of the paper out run a 15 minute dry cycle.
Use distilled water to lower the risk of water staining
john hall

_________________
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

I bent some flamed Koa sides in my fox style bender and in the upper bout 2 of the flames kinked.
They didn't break and I managed to scrap the kinks flat on the outside, I also added some reinforcment on the inside.


Peter

Bent some high flame at about .080" 310 degrees. No problem...

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

With high flame the runout tends to lift on sharp bends.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Gene buddy be sure to note what John said about using paper - Koa can get a greenish stain when directly in contact with metal slats. Using craft paper (brown stuff that Stew-Mac uses as packing) avoids the green stains.

What others said on heat and Howard on grain lift sharp. Bending any woods seem about same to me. I use the white bakers parchment and not the kraft paper, just what did at other shop on really flamed maple archtops,and cutaways. Probably no difference in them. Wouldn't go to much on the water though.

I used an aluminum slat next to the wood when I bent Koa. I got some serious green marks. Most of it sanded out, but I know where it didn't. So definitely use something between the wood and metal.

OK guys, Thanks... I normally use bakers paper, but I'll be sure it covers all the
wood very well. Green marks- yuck...

_________________
Gene

Politicians and diapers must be changed often, and for the same reason- Mark Twain