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Lacquer or Poly over Frenc Polish ??
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Author:  rich altieri [ Sat Dec 27, 2008 9:33 am ]
Post subject:  Lacquer or Poly over Frenc Polish ??

I have a couple of old builds that I did with FP and now, a couple of years later wanting to poly them. The question is, can I simply sand and refinish over the FP or do I need to strip? Wondering if the oil use for the FP will cause fish eyes as well. I did strip the soundboards to bare wood, but didnt want to do the backs and sides as they are well filled and smooth.

While I really do lik to FP, it doesnt hold up to the beatings I give these two units and not too concerned about the sound impact as I use these two with electronics most the time.

Author:  Andy Birko [ Sat Dec 27, 2008 9:42 am ]
Post subject:  Re: Lacquer or Poly over Frenc Polish ??

I always use shellac under waterborne lacquer with no problems. I've also used it under water based polyurethane as well. I would imagine that the oil is either long gone polymerized by now. A scuff sand should do the trick.

Author:  Michael Dale Payne [ Sat Dec 27, 2008 10:07 am ]
Post subject:  Re: Lacquer or Poly over Frenc Polish ??

first the oil that was used during french polishing is removed during stiffing and spiriting off so the oil is no issue. Now for the real problem you do have. Assuming you did build a full French polish film 6-8 body sessions and 4-6 glazing sessions you have a 4-5 mil film thickness. Now you want to put 4-6 mil poly film over that you will then have up to 10-11 mil of finish on these guitars. this is a lot of finish.

So the way I see it the FP finish is not, the problem, it is the thickness of the final product you will end up with that is the real problem.

Author:  Hesh [ Sat Dec 27, 2008 10:15 am ]
Post subject:  Re: Lacquer or Poly over Frenc Polish ??

Happy Holidays Rich my friend!!!

Author:  rich altieri [ Sat Dec 27, 2008 1:19 pm ]
Post subject:  Re: Lacquer or Poly over Frenc Polish ??

Thanks for quick reply guys. I know the answer I didnt want to hear is the right answer - strip all the finish !!! gaah gaah

Michael - you are right - I did strip the top and the build of FP was significant. I think if I dont strip it, the sound will be effected more than expected. So - back to the workshop to put on the gloves and get the acetone out. How I hate re-doing work. Funny thing though - This guitar had a problem with the neck angle which I then compensated by playing with bridge thickness. The fretboard had a dip from the 14th to the last fret that was significant. Not sure how I missed it then - perhaps experience, perhaps rushing it - but I now have the neck angle corrected, the finger board lies nicely on the soundboard and the bridge will be fine - will end up with a little more saddle to work with - saddle was very low and no room to go further.

So - I guess the repair process is going well and worth while. Now I have to strip the back and sides and will end up with a really nice guitar. Thanks to all of you on OLF - and happy New Year to all.

Hesh - I dont do alot of posting because everyone is so quick here, I rarely have nothing to add, but I do check it out almost daily when not traveling. Hope to see some of you guys at ASIA. I have it in my book and hoping to attend at this point. Need to start saving up some extra cash - last time I went, I got a little crazy as John Hall will probably confirm laughing6-hehe laughing6-hehe

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