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Scorched my sides; HELP!
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Author:  BlueSpirit [ Sat Dec 10, 2005 5:37 pm ]
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Okay, I'll be the 1st to say it. Dumb, dumb, oh that's dumb!
I just finished bending my 1st side on my new Koa wood, and what did I do? I laid the heating blanket on the wood and the new spring steel slat I got from John at Blues Creek, on the heating blanket. I used two heating blankets and so both sides of the side got torched. The result. My wood now looks like the coils in the heating blanket. Is there any hope for this Koa. I can sand out the scorch marks, but what I need to know is if the wood can still take the stress that it will be under.
After you've stopped laughing, any help would be appreciated.
Author:  Daniel M [ Sat Dec 10, 2005 9:30 pm ]
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Well... It's sure worth a try.
I would sand it clean & leave it for a few days to absorb some moisture naturaly again before you shock it with the water spritz. If you are in a low humidity zone, you might try wafting a bit of steam over it to get it rehydrated.
At this point, what've you got to lose?
Hopefully, you're not building a really tight bend cutaway.
Good luck! (bet it works fine)
Daniel
Author:  LanceK [ Sat Dec 10, 2005 10:53 pm ]
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Doug, did you wrap your wood in either foil? Spring steel will stain you wood.
Author:  tippie53 [ Sun Dec 11, 2005 12:11 am ]
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       You can try and sand off the marks but first take 2 pieces of paper. Wet them and use that between the wood and the slats when you bend. I use Kraft paper but white trtacing papet will also work. ANy thing that can take water into it. This does 2 things, It acts as a reseviour and brings more water into the mix and that helps to avoid scorching, It also will not leave as many water marks.
      With 2 blankets you get alot of heat very fast. One of the reasons I don't use 2. Watch the temp and at 250 start bending. I think with a little creative staining you should be able to hide the scorch marks if they don't sand out.
john hall
    
Author:  Brock Poling [ Sun Dec 11, 2005 1:33 am ]
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How scorched are they. Mine get a little toasty some times and I have never had a problem with the finished guitar.

Koa is funny like that.... you have to really stay on top of the heat.
Author:  BlueSpirit [ Sun Dec 11, 2005 10:18 am ]
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Thanks for the replys, guys.
Lance: no wrap of any kind.
John: the sides are bent. I was watching the temp and started the bend at 240, But the problem was that I laid the blankets against the wood instead of the slats against the wood. I know, I know.
So Brock: They are scorched enough to get the impressions from the coils inside the blanket, imprinted into the wood. They sanded out, but what I'm wondering is if the strengh of the wood has been compromised.
Thanks again guys. Let me know your thoughts. The sides are in stasis now, just sitting in the mold hopefully absorbing moisture.
BlueSpirit38697.7643287037
Author:  Shane Neifer [ Sun Dec 11, 2005 10:26 am ]
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Doug,

You will be fine. It is all cosmetic in my opinion. If you can sand it off and still maintain some thickness in the sides then you are good to go. I would not try to rehydrate. Let that happen in your shop while the sides in your mould. These are thin bits of wood that all get sucked down pretty low in the moisture content if you bend with little water (as most do). The Acacia I bent stained with a couple of small scorches, but seems to sand out OK.

Good luck Doug.

Shane
Author:  tippie53 [ Sun Dec 11, 2005 11:42 am ]
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   I agree that the strength isn't effected and you are fine.
John
You allways learn more from a failure than you will from success
Author:  Brock Poling [ Sun Dec 11, 2005 12:11 pm ]
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Sometimes too much heat can make the wood brittle. That might be a problem, but if I were in your shoes I wouldn't worry about it.

Author:  Howard Klepper [ Sun Dec 11, 2005 12:55 pm ]
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sand or scrape until the scorch is almost gone and measure. If you aren't
under about .065" you can make them work with some side bracing.

I have heard of many variations in the wood/metal/blanket sandwich (I
personally never put the blanket against the wood), but I never heard of
using two blankets before.
Author:  BlueSpirit [ Sun Dec 11, 2005 5:15 pm ]
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Thanks Guys, I'll keep my fingers crossed.

Howard, putting the blanket againt the wood was my mistake.
Author:  TonyKarol [ Sun Dec 11, 2005 11:48 pm ]
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I use a blanket as well, and the sandwich has always been spring steel slat, foil wrapped wood, blanket, slat - bend it. Controlling the heat is the most important thing, I never leave the balnket on full tilt once the waist is down, I crank down to about 90 volts or so - I use a big variac to control it.
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