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So I’m finishing up my 3rd instrument using KTM-9 and am very pleased with results. I had no problems with it as far as the blue tint or anything else. It goes on smooth and is clear as glass.

After looking at the last 2 (I just finished the spraying yesterday) I can see that the finish is a bit thick on the necks and sides. Generally I shoot a few more coats on the back, sides and necks than I do on the tops. I’m not real worried as I will sand it back before buffing in a few weeks. But I wanted to know how many coats you other KTMers are using? I find this stuff builds fairly fast. I will continue to experiment with it but I thought you guys who have some more experience with it could help me out.

I'm spraying the KTM with and HVLP system over epoxy filler.

Thanks
JoshJosh H38538.5828240741

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Josh House

Canadian Luthier Supply
http://www.canadianluthiersupply.com
https://www.facebook.com/canadianluthiersupply?ref=hl
House Guitars - Custom Built Acoustic Instruments.
http://www.houseguitars.com

I shoot a total of 6 some times 8 but mostly six. On the necks though I only shoot 4-5

but It would depend of corse on how thick you lay each coat. I try to get it just thick enoug to insure uniform coverage. I level sand lightly after the 3rd and total level after the 6th on bodys.MichaelP38538.5988078704

Mike is about right on if you have done your prep work good and have a nice level surface to start with. This stuff builds pretty fast and if you shoot nice wet coats, usually 3 a day leveling after the 1st day, you should be good. The important thing is the prep. Get all the pores and any gaps filled before you start spraying. If you miss any, make sure you get'em before you level sand the 1st days coats, then level sand and spray the last coats..

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Tickle your guitar daily, and it'll tickle you back.

Thanks guys

I was up around 8 coats which seems like a bit much.

This should make my life a lot easier.

Josh

_________________
Josh House

Canadian Luthier Supply
http://www.canadianluthiersupply.com
https://www.facebook.com/canadianluthiersupply?ref=hl
House Guitars - Custom Built Acoustic Instruments.
http://www.houseguitars.com

And keep in mind that the thicker the KTM, the bluer (is that a word?) the tint will be. So ideally you will want it as thin as possible. MP is right on with the 6-8 (though I would lean more toward the 6). When wet sanding, it is much more difficult to sand through than nitro so unless you are hogging material with 80 grit you should be in pretty good shape.
I've only done one neck with KTM but I've done LOTS and LOTS of test swatches. I think on the next guitar I'll go even thinner to 2 coats/wetsand/2 more coats. I think that will work fine as long as the surface is prepped well.

May be why I have never seen this bluish tint on my guitars. I took several outside the other day after John K posted his remarks and didn't see any blue in there. I did however see the blue when I tried the KTM-4 finish.

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Tickle your guitar daily, and it'll tickle you back.

This has been helpful, but I am wondering what you guys are doing with your sanding.

I am sanding between days with 600 3M no-load dry paper. I wet sand to 1500 and buff when it is cured.
What are you guys doing? Are you set up to power sand or are you doing it by hand? I have done most of the sanding by hand so far. I am starting to expirument with the 600 no-load on my palm sander.

Josh

_________________
Josh House

Canadian Luthier Supply
http://www.canadianluthiersupply.com
https://www.facebook.com/canadianluthiersupply?ref=hl
House Guitars - Custom Built Acoustic Instruments.
http://www.houseguitars.com