water stains remaining on wood after bending?

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BruceC

water stains remaining on wood after bending?

Post by BruceC »

Hi.
I am part way through two kits, one came with pre-bent koa, the other pre-bent myrtle. Both sets have rather nasty stains which are I am sure are from the bending process. No stains on the backs.
I have tried taking them off with rags and hot water, but there is little or no change. I noted that while the wood was wet I could still see the stains, they didn't 'blend in' with the wetness.
Should I try solvents? (I don't want to bleach the wood.)
Will it sand out? How much sanding are we talking about? I tried a bit and it didn't seem promising.
It seems that maybe this could be handled more easily before assembly is complete. I'm about to install the backs/fronts, but is there anything I should do first?
Thanks in advance!
tippie53
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Joined: Fri Mar 03, 2006 7:09 pm
Location: Hegins, Pa
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Re: water stains remaining on wood after bending?

Post by tippie53 »

a light sanding should remove the staining. To be sure try a little at the area of the tail block. Others I am sure will add to this. Try using 120 grit and see what happens.
John Hall
Blues Creek Guitars Inc
Authorized CF Martin Repair Center
president of Association of Stringed Instrument Artisans
http://www.bluescreekguitars.com
Ken C

Re: water stains remaining on wood after bending?

Post by Ken C »

Bruce, where do you place your heat blanket? I put the blanket on top (on the outside of the rim). The heat on top seems to push the moisture out through the inside of the rim, so when I get staining, it is always on the inside of the rim. I have never had staining on the outside. As John noted, what little staining I get on the inside is easily sanded off.

Ken
mjmeehan
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Location: Bethlehem, Pennsylvania

Re: water stains remaining on wood after bending?

Post by mjmeehan »

Bruce, John nailed it. I had myrtle that was stained at the waist and it sanded right out, no problems. But I understand your concern, it can look pretty nasty.
tippie53
Posts: 7019
Joined: Fri Mar 03, 2006 7:09 pm
Location: Hegins, Pa
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Re: water stains remaining on wood after bending?

Post by tippie53 »

after 136 guitars I only seen one that didn't come out . Darn Chlorine
John Hall
Blues Creek Guitars Inc
Authorized CF Martin Repair Center
president of Association of Stringed Instrument Artisans
http://www.bluescreekguitars.com
BruceC

Re: water stains remaining on wood after bending?

Post by BruceC »

Thank you all. That calmed my nerves and the 'test section' I did looks wonderful.

Just to clarify for Ken, who asked what side I put the heat on, they arrived pre-bent, so I don't know the answer. However there was staining both inside and out. I guess predominantly inside, now that I pay attention. As a production shop they might have been using the boiling waterbath method; dip for 15 seconds then drop in a heated press for 2 minutes. It is slick to see. But I really don't know.

Thanks again!
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