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Mohawk Piano Lacquer10/2
There are claims that this nitrocellulose lacquer product cannot be recoated even a few months later without possible wrinkling issues. I wish I had been more aware of that possibility, I'm using it for the first time on a Chickering grand. I've already stained, sealed, filled, sealed and started my many topcoats.
If any reader has any experience with this coating, please share your experiences and opinions.
Incidentally, the world of "topcoat finishing" has been dealt a real blow by Sturh (Cooper Power Tools) and National-Detroit no longer making dual-pad rubbing machines. Shoot & scoot/spray & show off-the-gun finishes have no real place in the piano world.
I don't like recoating any lacquer..it don't happen all the time...but 1 out of 10 will wrinkle. And a huge sand to recoat gegins till I build past the wrinkling...
I have never tried using any thing in nitro but lacquer thinner. mihht be something to add that helps with this issue..
I would call Mohawks tech..I talk with them about other issues and they seem pretty good at giving " we don't recommends, but I may work" kinda advice..
Is there a particular reason you chose a less durable, inferior topcoat over say CV' or ployester?
I'm not set up to do polyester. But even if I were, it's not to my liking to put polyester on a piano that's pre 1940's. Lacquer is much easier for a small shop, much less labor intensive.
Conversion varnish is totally wrong for any piano. And why? Because it's not done. It's a cabinet coating. It's an office furniture coating. It's suitable for dinette sets. For instruments (guitars, banjos, pianos, etc.) it's just not done. It might have something to do with that it's an unforgiving finish with dry mil limits, or maybe it doesn't look as amazing as other instrument-grade finishes if it's to be rubbed out. And maybe it's too easy to cut through a coating? Whatever it is, pre-cat, post-cat, and conversion varnishes aren't chosen by any instrument manufacturer as a finish.
Instrument manufacturers use lacquer, polyester, or plural-component polyurethane. Shellac, as as sealer, might be part of a finish schedule. I include it to use as my initial washcoats.
Thank you for such a concise answer, i too love the virtues of nitrocellulose lacque but times and applications change, conversion varnish is an easy to manipulate finish and i think p erfect for small shop applications.
I would like to chime in on the lacquer vs cv..
As normal lacquer can only be built at 5 mils wet
CV..far superior in look, feel and durability..can only be stacked at 4 mils
And dry I think it's 1.75 mils of build..
So nitro is really the only option.
Polyester is just to much of a pain and really hard on equipment..and tends to dry with a haze..not very clear
I use the coating that is best suited to the job
Coming soon: Pianolac waterborne lacquer. Developed for piano and high build wood finishing,
When? I remember hearing that it was coming soon last year
It's in beta testing. Should be ready for commercial use in one month.
Dan, I also found out the same thing you did. Mohawk/CCI has a resin in that formula that crosslinks in about 4-5 days. This then makes it non recoatable at that point. If I remember right once a period of time passes it then becomes recoatable again but it is a lengthy time period.