What Grit To Start WET Sanding with KTM-SV

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tippie53
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Re: What Grit To Start WET Sanding with KTM-SV

Post by tippie53 »

we all may do things a little different but what I can tell you what I do
600 first to start cutting through the orange peel surface bumbs
when I am about 1/2 way through them I use 800
when I am just about bottomed I go to 1000
then once leveled I do 1500 2000
then buff and polish
after that I use Maquires swirl remover and 3m Hand glaze
John Hall
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president of Association of Stringed Instrument Artisans
http://www.bluescreekguitars.com
johnnparchem
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Re: What Grit To Start WET Sanding with KTM-SV

Post by johnnparchem »

Take care with the final coat sanding. KTM-SV does not burn into the previous coat. If you sand through your final coat you will get witness lines. I found it hard to brush on KTM-SV and sand it without sanding through somewhere. Ultimately I got a spray gun and sprayed the final coat on a completely level surface. That coat took almost no sanding before I polished it out.
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Re: What Grit To Start WET Sanding with KTM-SV

Post by johnnparchem »

mike288 wrote:I was really hoping to avoid using a spray gun. Do you think it would be possible to user 400 very lightly to get the brush marks out before using 600?
I am not sure you have to wait a month with this finish it is not Nitro. I say this because then I could tell you sure try the 400, if you sand through the last coat apply another. If you are waiting a month in between though ... The witness line are visible as you are getting more to the polishing grades of paper.

Here is the writeup that I used when I used it.

http://www.newenglandluthiers.org/conte ... inish.html
Last edited by johnnparchem on Sat Mar 11, 2017 10:03 am, edited 1 time in total.
johnnparchem
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Re: What Grit To Start WET Sanding with KTM-SV

Post by johnnparchem »

mike288 wrote:Hey John, thanks for the help. The link you gave me doesn't work. Do you think you could try again, or private message me it?
whoops
http://www.newenglandluthiers.org/conte ... inish.html
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Re: What Grit To Start WET Sanding with KTM-SV

Post by johnnparchem »

i did not use water, but i usally do not with water based finishes.
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Re: What Grit To Start WET Sanding with KTM-SV

Post by ruby@magpage.com »

Johnparchem

I am a little worried about information that is 11 years old. I am sure that all of these finishes have undergone several changes in composition in this time. Have you recently used it with success? I am a month away from needing something and would like to try something new.

Ed
Ed M
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Re: What Grit To Start WET Sanding with KTM-SV

Post by johnnparchem »

ruby@magpage.com wrote:Johnparchem

I am a little worried about information that is 11 years old. I am sure that all of these finishes have undergone several changes in composition in this time. Have you recently used it with success? I am a month away from needing something and would like to try something new.

Ed
I never was able to brush and level, I would apply a coat that looked good, but I could never level without sanding through the final coat. I had to spray.

I stopped using it. As I mentioned before you really need to get a perfect last coat to avoid witness lines. They almost disappear when buffed but they still show up with the right light. Also it is really hard to repair without obvious witness lines. I switched to EM6000 when I want a water based lacquer. There are those who still like KTM-SV though so you can probably get more encouraging information from them.
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