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Had my first problem ever with KTM-9, I am sure the issue is user induced, but I have never had this isse before. The top and sides are perfect but there appears to be pin head sized viods at a dozen or so places on the back spred out over 1/3 the length. I sanded to see if they would sand out but started to burn through just as I got to them I did not see them on the day two leveling. but I guess they were there

I am assuming I will need to sand out and re build the film.......Darn I was shooting to deliver next week

PS I was using IR lamps at 24" from the body to speed the cure. The top and sides do not have this issue. It may be the onset of overheating the film but I would have suspected that it would happen in the higher sections of the film first not the lower.

Sounds like a couple of things could have happened...

1. You laid on too thick a coat (maybe the guns not adjusted right).

2. Your not thining the KTM enough.

The only time I have seen that is when I leave it too thick, it gets air bubbles trapped and you end up with pinholes like that. I know that Doolin shoots it straight but he and I chatted at HB and I told him that I always thin it and get better results that way, he's doing a new thing with the epoxy filler now that I need to try before I can explain.

I would let it cure a bit, get some 400 and sand them out and start building again. Try some DA in your mix or if you have some a little more, KTM likes lots of thin coats...

Hope that helps...

-Paul-

_________________
-Paul-

Patriot Guitars

I put on 4 thin coats a day. I did get a one run when I got to close on the seconday shoot but when I leveled on the forth day it looked ok, I was thinking that it was heat induced by I suspect you may be right.

by the way I did a little test with KTM-9 clear vs Target I.E. Stew-Mac waterborn on glass to compair clearity.
Target is many times more blue than Ktm-9 clear. I could not see any percievible blue in the KTM.

It could be heat induced as well, I can't tell without feeling the finish to see how warm it is. What I would try is to leave it for about an hour to flash off and then put the lamps to it.

I have 5 guitars now finished in KTM and think I've gotten it down pretty good, I got lot's of comments on my finish at the show and Mike Doolin had some kind words as well. The fanned fret shows very blue on the back at in sunlight, I think that was because I was in a hurry and put the spurs to it. But the thin body had the same issue and it just went away after about 6 months. I'm going to start adding just a touch of amber to my KTM and see how that fares. I'm not sure we will ever get away from that using a water based finish....

But I'm also going to try sending out some of my work to Adam Stark to finish, I'll be sending him my experiment guitar to see how he does with it and if it's good then I might just stop doing finishes in the shop and work on just building...

Cheers

-Paul-

_________________
-Paul-

Patriot Guitars

I'd bet it's heat induced. As you heat the surface, any air trapped under the finish will expand as bubbles. It's east to trap air on raw wood, which might have happened if you sanded through your sealer in that area.

mo I did not sand through my sealer prior to the voids appearing I sand through trying to remove the viods. My guess is Paul is right I got a bit thick.

Now to sanddown the back and respray

Sorry if I offended. That wasn't my intent at all. I was trying to quess at a reason for the air being trapped. There are other things that may cause that to occur, especially under a water based finish.Jerry Hossom38587.8111111111

I was experimenting with wet samples seeing how close I should place the lamps to the surface. When I got too close I got the bubbles as you discribe. Try that with some scrap and see if it duplicates your problem then at least you could adjust for it.

Jerry, I did not take offence. I was just being sure everyone that reads this thread knew that that allwas normal when this happened.