Lacquer over old Shellac?? - Woodworking Talk

Safegyde · 02-14-2009, 07:37 PM

I have a piece I am working on that is fairly old and the shellac is cracked all over. Most of it is still together, but in a few spots it has starting to fall away from the wood. I want to keep the old shellac finish on it, but I want to protect it and make it look a little better. Does anyone foresee a problem with spraying on a lacquer? What about nitrocellulose vs. acrylic lacquer, either one better than the other?

thanks for the info.

BHOFM · 02-14-2009, 08:15 PM

I had some pieces that were very old with a shellac finish
that was in very good condition and I used water base poly.
The Satin finish did not change the color or look at all.

Gary Beasley · 02-14-2009, 09:02 PM

I'm not recommending this, just curious- what would happen in a case like this if you were to use some denatured alcohol to redissolve the shellac so it would readhere to the wood. Would the color change much? Would it even work and how would it be done best?

Rob · 02-14-2009, 09:14 PM

Quote:

what would happen in a case like this if you were to use some denatured alcohol to redissolve the shellac

I did this once with an old desk that was full of shellac cracks. I cleaned it first to get the dirt off and then applied alcohol pretty liberally with a brush. Came out pretty well.

johnnie52 · 02-17-2009, 10:53 PM

I have just started to refinish an antique cedar chest that my wife inherited about a year ago. The piece had been in an outside storage shed in the Florida heat for over 12 years before she got it.

Look at the first picture and you can see the kind of damage that the heat and humidity caused to the original shellac finish. The second picture shows the top after using denatured alcohol on it. One application, using #1 steel wool to rub it down and the damage is gone! I could almost get away with simply rubbing it down with more alcohol to smooth out the finish.

There is still a lot of shellac left on the piece. So it would need a lot more work to get it ready for either poly or lacquer finishing. However, its just about ready as it is to receive fresh shellac.

Think about it..... 3 good coats of shellac and waxing with a paste furniture wax and the shellac will stand up to almost anything you can throw at it. Plus there is a lot less work involved to prep the piece for finish and between coats with shellac.