Official Luthiers Forum!
http://www.luthiersforum.com/forum/

Sherwin Williams alternative?
http://www.luthiersforum.com/forum/viewtopic.php?f=10101&t=27081
Page 1 of 1

Author:  jsmith [ Tue Apr 20, 2010 7:07 pm ]
Post subject:  Sherwin Williams alternative?

I've been using Sherwin-Williams vinyl sealer as a base coat (under nictrocellulose) for over 20 years. It has 24% solids and fills nicely, but it's now gone up to nearly $56 plus tax.

How many of you--who finish with nitrocellulose--use a different brand vinyl sealer--or a sanding sealer? Also, you who use a premixed shellac, what brand do you use? And to all who reply, how many coats of your respective product do you apply before going to the nitrocellulose?

Thanks to all in advance.

Author:  bluescreek [ Wed Apr 21, 2010 5:56 am ]
Post subject:  Re: Sherwin Williams alternative?

I found that mixing the brands often tends to have issues later. I use the same brand sealers and nitro . Behlen and SW you get what you pay for

Author:  woody b [ Wed Apr 21, 2010 6:10 am ]
Post subject:  Re: Sherwin Williams alternative?

I usually use shellac. Zinsser's seal coat to be exact, but I've also had good luck just starting with a thinned coat of lacquer. To me $56 a gallon doesn't sound high for a vinyl sealer, but 24% solids sounds high for a musical instrument sealer. Do you thin it before spraying? I'm just curious.

Author:  Howard Klepper [ Wed Apr 21, 2010 9:09 am ]
Post subject:  Re: Sherwin Williams alternative?

No sealer needed for nitro. It doesn't add anything positive to the result. You shouldn't need to fill with a sanding sealer if the surface is well prepped.

Author:  bluescreek [ Wed Apr 21, 2010 11:21 am ]
Post subject:  Re: Sherwin Williams alternative?

I use CF Martin's finish schedule and use the sealer between the filling process to avoid bleeding .

Author:  Mike OMelia [ Wed Apr 21, 2010 12:28 pm ]
Post subject:  Re: Sherwin Williams alternative?

Howard Klepper wrote:
... You shouldn't need to fill with a sanding sealer if the surface is well prepped.


Are you referring to epoxy or egg whites, etc?

Author:  Howard Klepper [ Wed Apr 21, 2010 3:20 pm ]
Post subject:  Re: Sherwin Williams alternative?

I'm referring to flat. I raise grain with shellac, and then sand it back to wood before going to nitro.

Sanding sealer is designed to speed production in commercial shops by allowing for somewhat sloppy surface prep (i.e., scratches). It fills scratches and it is designed to sand better than plain lacquer (or whatever finish the sanding sealer is based on). So you spray it and then sand again to get a flatter surface. It does not improve the adhesion of lacquer to wood--on the contrary, it can hinder it. Other finishes may need a barrier coat on the wood, but nitro lacquer does not. Vinyl sanding sealer does not have the same problems with adhesion and translucency that stearated sanding sealer has, but it does nothing to improve the finish. When the manufacturers say you should use vinyl sealer with their musical instrument lacquer, they should add IF you choose to use a sanding sealer at all. But they don't mind selling you an extra product you don't really need.

Author:  jsmith [ Wed Apr 21, 2010 3:21 pm ]
Post subject:  Re: Sherwin Williams alternative?

Thanks all for the info. I actually sprayed my first fifteen or twenty guitars with straight nitro with no problems. Then, I read that lacquer didn't adhere well to bare wood, so I switched to a base coat of vinyl sealer. In retrospect, I have one of my first guitars from '79 and, other than myriad dings & scratches, the lacquer is still fine. Guess I'll go back to exclusively nitro finishes.

Thanks again, John, Woody and Howard.

Page 1 of 1 All times are UTC - 5 hours
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/