Can I Mix These Finishes?

Hi All, I have the body sprayed with Cabot's Oil Based Satin Cabothane Clear Polyurethane Timber Varnish Aerosol, but i'm not happy with the result. This was sprayed over the entire body and front of the headstock. The headstock and body front have a quilted maple finish.

The main issue is i can't get flat, so wondering if i can return to the way i've had the most success, using SCA Acrylic Paint, Clear? Can i just rub back with steel wool and then spray over the top?? With SCA Clear, i know i can get a good finish that can be sanded and polished (i didn't like the flat look on the quilted maple).

Thoughts?

The general rule (and I mean general) is you can apply lacquer over poly, but not poly over lacquer.
HOWEVER, there is no guarantee there won't be issues.

That said, there are a couple of things to consider:

How long since the polyurethane was applied? Has it completely gassed off?
A very unscientific way to tell if the poly has fully cured and gassed off, is the old sniff test. Literally place your nose close to the body and sniff... If you can still smell any solvent, it hasn't finished evaporating.

One suggestion I'd offer is applying a few coats of dewaxed shellac over the poly (presuming it's fully cured) and apply the acrylic lacquer over the shellac. Shellac is a wonderful product with so many uses, and one of the best for compatibility with other finishes.

You can buy aerosol shellac (Zinsser Bulls-Eye Shellac - distributed by Rustoleum in AUS) but it's not always easy to find and fairly expensive for what you get. The best, most economical method is buy dewaxed shellac flake and dissolve it in methylated spirits. If you have a spray gun you can spray it, if not, you can wipe it on. I recommend sourcing industrial strength 100% methylated spirit, not the 95% Diggers stuff you'll find at Bunnings or Woolies.

Hope this helps.

Its been about 4 to 5 weeks since the poly was applied, so it should have gassed off by now but can try the old sniff test :-)

I'm really worried about what might happen as i don't want to ruin the colour finish if something goes wrong and i have to fix or restart. I have a really good colour finish and its just the clear that i'm not happy with. I usually use the SCA clear but i thought i would try the cabothane product, but for some reason, even after rubbing back with steel wool to a nice flat surface, the next (and would be final) spray always leaves ripples, like waves that you can see in the light. When i try and wet sand that and polish it actually makes the clear a little cloudy.

I might see if i can try the shellac...i have metho but not the 100% stuff.