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I need some advice on touch up solutions or refinishing solutions.

This is my first time spraying KTM9. It’s really my first time spraying anything.
It looks like I sanded/buffed through a couple of small spots. One spot on the top and another on the side. It has been about 3 weeks since I sprayed and about 1 week since I was level sanding and buffing.

Is it ok with KTM9 to spray over the existing finish and resume? In the instructions that I have it mentions that spraying anything over 24 hours may not adhere well to the previous coat so I’m wondering if I need to sand back to bare wood and go from there or if it’s ok to spray some touch up spots and then resume level sanding and buffing after letting that cure another 2 weeks.

Also, I don’t know if I sprayed too thin or what. Is there any way to gauge the amount of paint being applied? I am spraying with the Fuji HVLP unit and I take about 1 second doing a pass across an area of the guitar so the back or front of the guitar might take me 4 or 5 seconds to spray. I was trying to avoid spraying it on too thick and getting sags. I did 5 coats like that at hour intervals one day and then 5 more at hour intervals the next day. Let cure 2 weeks and then level sanded and buffed.

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Thanks,
Blain

http://www.ullrichguitar.com

"89.67% of all statistics are made up on the spot."

yes you can spray over the existing film. That said if you truly sanded and buff through all the way to wood your sealer is gone and the color of the buff through area will likly be slightly off.. now that is assuming you used a sealer. If you did not use a sealer then the match will be better. now before you re spray Clean with naptha and allow to flash completely off. lightly sand with 320p then wipe lightly with DA and allow to flash off. this will allow for better burn in on the cured film. Now you can spray.

Thank You Michael

I'll give that a try.

_________________
Thanks,
Blain

http://www.ullrichguitar.com

"89.67% of all statistics are made up on the spot."

Michael's advice is sound. The waterborn lacquers are easy to sand through -- in my experience (10 instruments) 12 coats is cutting it close, 15 gives me a better chance of avoiding sanding through.

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Kent

Facebook Page

The differences in application thickness are striking, I am going with 4 coats of KTM9 and am thinking about trying 3. I guess every gun is different......... Mikey

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The Biggest Little City, Nevada
www.hammondguitars.com
I love building guitars!

It's good to know the different spray schedules that others have. I agree. It sounds like either every gun is different or every person's technique is different.

I sprayed about 10 coats, but as I said I sprayed very quickly across each pass. I think next time I'll spray 7 coats per day instead of 5 and see where that leaves me.

The areas that I sanded through are very small and there's only 2 of them so I think just a little more tweaking and I'll be all set with a spraying technique that should work for me.

In general though, I'm really impressed with the KTM9. I was easy to spray, leveled well and buffed well, and worked great with the black dye that I used on the headstock.

_________________
Thanks,
Blain

http://www.ullrichguitar.com

"89.67% of all statistics are made up on the spot."