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My first attempt at spraying KTM-9 today, 4 coats at 1 hour intervals, looks really nice...EXCEPT, the texture when touching is not smooth at all it feels like 220 grit sandpaper. Did I put it on too thin? There seems to be a very small line between too little and a run, does this seem like my problem? Or do you just sand and polish out the rough finish?

Thanks,
Greg

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Gwaltney Guitars

yes it sands out. The second days coats tend to go on smoother and wil hopefully require less sanding

Greg...

You can put a little denatured alcohol in the mixing cup and that will help it flow a little better, when I was using it I did 4 coats, left it overnight and then sanded back with 800 to smooth it out and then would shoot again. When I started getting close I thinned out the mix a little more, it takes a little patience to get those final coats right but it pays off in the end.

Also I don't care what anyone says, you need to wait as long as possible with KTM before buffing out, I would do nothing shorter than 3 weeks, I know this goes against some peoples advice but the best result I got from it was a guitar that sat for 4 months before I could get my hands on it. I buffed it out and it turned out the best...

Good Luck

-Paul-

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-Paul-

Patriot Guitars

Don't worry.....
Tomorrow sand a little, apply a little DA with a paper towel and shoot again.
After it cure you can level sand and it will be just fine!

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

Greg

The tips above are spot on.

Pauls advice about drying time is also. I don't know how long it takes this stuff to complete harden but the longer you wait the better results you can expect. If I can I like to give it 3 to 4 weeks.

Cecil

Thanks guys,I sprayed my 2nd coat yesterday using a different gun, it went on way too heavy, runs everywhere, I wiped it down with DA before it dried so I wouldn't have to sand as much today. Looks fine, I'll sand and re-spray this evening.

Greg

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Gwaltney Guitars

Greg, I think that's the issue with the waterborne. Getting your gun set up correctly. With my new gun it has a regulator at the gun so I have really good control of the pressure. As the compressor is out back and I'm running 50' of air line. Between coats the compressor may have pressure at the gun between 30-50 psi.I find that 40psi is ideal. I can get a good wet coat without milk or runs. Do you have a good sense of the air pressure at your gun?Tomas38894.4206018519

Not a big issue at all. In fact in my opinion it is better to go on a bit thin and over atomized on the first couple coats than to go on too wet. I do not use DA in my mix. I run a Igasol Rann 2708 HVLP gun with a regulator at both the compressor and gun. My gun output pressure is about 8lbs and my input pressure to the guns regulator is 30-35lbs. It take some practice to get the atomization just right. I like to test on cardboard be cause the cardboard is easy to see the dispersal pattern and media flow rate in any lighting.