Painting Over Existing Finish

[MarkII]

Hello, I am soon to be undertaking my first guitar finishing project on an old squier strat I have.

Now, its an off-white cream colour, and I have had the suggestion from my dad that I take advantage of this, and when I repaint it I just sand it down to a matte finish without removing the paint fully, and then prime and paint and so forth over the top of that. His reasoning for suggesting it was that it would be taking advantage of the good quality finish thats already on it, so what i would be doing is really just changin the colour.

Now, he doesnt actually know that much on the subject and neither do I, so I was wondering what someone who knows about these things would say about this idea. if i used paints that wouldnt react with the pre-existing finish, would it be ok?

[Louis frickecello]

Hi, your dad its not wrong at all, you can take advantage of an existing finish but be careful with paint chips and deep scratches because new paint coats will tend to "copy" all defects from the surface, also you will have to be more conscious about lacquer/paint thickness.

First you have to make sure what is the kind of finish your guitar has...

Wheres how:

Test with a minimum amount of lacquer thinner, do it in the pickup cavities for example, if the finish dissolves then it is nitrocellulose lacquer if nothing happens or just the test area is a bit stained then you have a polyurethane finish or a polyester finish.

I highly recommend that you paint you guitar with polyurethane if you are painting a solid color, is easier to apply, is harder and dries faster than nitrocellulose lacquer.

[al heeley]

A squier Strat will most likely have a polyester paint coat on it. As long as you sand back to allow the new paint to key in, you should be able to use polyester, acrylic or PU over the top without a problem or need to reprime. Priming is really only good to seal the pores of the wood and build up a thicker surface to help cover small scratches/blemishes; neither of which should be required in your case.

Edited May 19, 2006 by al heeley

[MarkII]

Thanks for the help

There are indeed a number of dinks and scratches, including one sizable chip in the finish. I was planning on filling those with a wood filler, or similar. In which case would it be advisable to prime, to avoid the paint going on differently to the different surfaces?

Also, if I am painting over the original finish, am I right in thinking that it wont be necessarry to put on as thick a coat than if I were painting onto the bare wood?

[al heeley]

Yes and yes. If you are not putting so much paint on (and you wouldn't need to) then the filler area needs sealing/priming first or it would show thru as being more porous than the old paint.