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Hairline Cracks in Macassar Ebony Back

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Re: Hairline Cracks in Macassar Ebony Back

Postby Philip Secrist » Tue Mar 07, 2017 1:17 pm

I think I will try that first. Thanks a bunch Barry! :)
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Re: Hairline Cracks in Macassar Ebony Back

Postby Barry Daniels » Tue Mar 07, 2017 1:21 pm

You're welcome.
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Re: Hairline Cracks in Macassar Ebony Back

Postby David King » Tue Mar 07, 2017 2:06 pm

I'll just say that CA glue can take a surprisingly long time to gas-off completely. I'd wait at least a week after a drop fill and I'll also roughen up the ca surface with 220 or 320 to get good adhesion. As it dries the CA will continue to shrink back so be prepared to drop fill with lacquer several times. This is good in a way because the CA always buffs out differently from the surrounding finish and you'll want to completely cover it up if you can.
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Re: Hairline Cracks in Macassar Ebony Back

Postby Philip Secrist » Tue Mar 07, 2017 5:20 pm

Hey Barry. Trying to sand down below the excess CA and respraying didn't work. So, I think I need to take the back down to bare wood, start over, and refinish it. Just to be clear, you don't think that using a good clear epoxy like West System or SB-112 System III to attempt to fill any pores that didn't get filled well enough the first time or more importantly to fill any other cracks that I can't see that may be starting is worth the effort? Just trying to maximize my chance for success. Thanks!
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Re: Hairline Cracks in Macassar Ebony Back

Postby Philip Secrist » Wed Mar 08, 2017 1:20 am

Sorry to ask one more question. Now that I have removed the finish down to the bare wood, is there anything more I should do to address the cracks? (I filled them with CA on the finish side before removing the finish and also from inside). I cleated the cracks on the inside. Do I need to reapply grain filler and sealer coat again just like if I were starting at the beginning or can I just spray a wash coat of Shellac (also as a barrier coat) and then go on on to the build coats? Thanks
Philip Secrist
 
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Re: Hairline Cracks in Macassar Ebony Back

Postby Barry Daniels » Wed Mar 08, 2017 12:11 pm

If you sanded the finish off and didn't use stripper then the pores will probably still be filled. However, if you sanded into the wood some then the filler may have been removed. Get a magnifying glass and look carefully at the surface to see if you have open pores. If not, then apply your shellac and finish. However, if you used epoxy fill on the original finish you should probably use it again to allow the back to better match the sides.
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