1st time Acrylic lacquer refinish

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Koen Lemmens
Posts: 3
Joined: Tue Apr 17, 2012 7:14 am

1st time Acrylic lacquer refinish

Post by Koen Lemmens »

Hi,

I'm a first-time poster, long time visitor to this forum, which has been a great resource for me in the past months. A few years ago, I acquired a Guild S-60D that was in a worse shape than I would have guessed from the pictures on Ebay. So it needed to be refinished, but only recently I took up the courage to do it myself, although I have no prior experience with spray painting and related subjects. It has been a steep learning curve and at one point I had to start over from the base coat, but now it has a nice acrylic white pearl finish (with some faults but I try to ignore them).

The only problem is: 2 weeks after final sanding and buffing, the finish is still too soft to put the guitar in a case or leave it in a guitar stand. The case padding leaves texture marks in the finish.

How long does it normally take for an acrylic finish to harden?

FYI, I used 2K automotive rattle cans: 2xwhite basecoat, 1xpearl coat, 2x#535 clear coat

That gave me roughly 4 coats of white, 2 coats of pearl and 4 clear coats, wetsanded with 800 grit every 2 coats and finally wetsanded with 800, 1200 and 2000 grit. Hand buffed with a Turtle Wax repair polish but I'm thinking of rebuffing with a high gloss polish.

Any thoughts of what I might have done wrong are appreciated, just don't tell me I have to do it all over again ;)

Thanks,

Koen
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Barry Daniels
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Joined: Thu Jan 05, 2012 10:58 am
Location: The Woodlands, Texas

Re: 1st time Acrylic lacquer refinish

Post by Barry Daniels »

The rattle can acrylic is the problem. Sorry to tell you this, but it may never get hard.
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Michael Lewis
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Location: Northern California USA
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Re: 1st time Acrylic lacquer refinish

Post by Michael Lewis »

You can try exposing the finish to strong light for a few weeks. It may or may not help. Some folks rig up a light box to help finishes cure, and I'm sure there are discussions of such in the Library.
Koen Lemmens
Posts: 3
Joined: Tue Apr 17, 2012 7:14 am

Re: 1st time Acrylic lacquer refinish

Post by Koen Lemmens »

Thanks all

Barry, do you suspect they used a lacquer retarder in the rattle cans?

Michael, that thought occurred to me too. The finish may not be outgassed completely though it's dry to the touch. Should I hit it with UV light or infrared (heat lamp)? I could try exposing it to the sun but the weather in Belgium is too shifty to leave it out there for extended periods of time.
John Sonksen
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Joined: Sun May 20, 2012 12:16 pm
Location: Portland, OR

Re: 1st time Acrylic lacquer refinish

Post by John Sonksen »

Koen, I think the acrylic lacquer stuff is soft by nature, probably to deal with wide fluctuations in temperature. I think this is one thing that is likely an advantage for cars and a disadvantage for guitars. I'm not sure if there's much you can do at this point to change that except giving it time. Still, it's hard to say whether you'll be satisfied in the end. Too bad, it sounds like you've got a fair bit of work tied up in it.
Michael Lewis
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Joined: Thu Jan 12, 2012 1:22 am
Location: Northern California USA
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Re: 1st time Acrylic lacquer refinish

Post by Michael Lewis »

Most of the light cabinets I know of use UV (black light), the Infrared makes heat which may help. Sunlight has both. What light frequency will help is dependent on what is in your paint.
Koen Lemmens
Posts: 3
Joined: Tue Apr 17, 2012 7:14 am

Re: 1st time Acrylic lacquer refinish

Post by Koen Lemmens »

Okay, we have a little indian summer this week, so I'll give it a shot and hang it in the sun.

Thanks for the input folks!
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