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Well it is out the door and done but I thought I would mention a problem I had on the Nara/Carpathian SJ.

Right at the waist, on both sides of the top I had spots 1/2" wide and about 1" long that no mater what I did the finish (ktm9) would not build. The issue was as if silicon had got on the top some how. The finish kept flowing away from these areas. But I have no silicon anywhere to contaminate it. The solution I finally came up with was to seal these areas with thin CA, sand a tooth into the CA and re coat with finish. After some rework this finally took.

Has anyone ever had this issue before? This is the first time ktm9 has ever given me a problem of any sort.MichaelP39028.4421180556

The thing that gets me is that it was at exactly the same place and the same size area on both sides of the top. And the top was sealed with shellac prior to finishing.

Michael,

I haven't really got a clue as to what caused it but given the bookmatching of the top could it be something that got into the wood there before it was bookmatched sawn?

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

i worked for a large furniture manufacturer for many years and one of our worst finish contaminants was found to be a particular barnd of deodorant used by one of our operators.. it took us weeks to isolate the problem.. all to say that contaminants can be off the wall and very difficult to pinpoint.. and can be very sporadic.. and, as dave said, may have been there when you got the wood..

Can wax paper residue cause this type of problem?

I did not use any.

If you still have the offcuts you might be able to test on this in the waist area. That is, if you want to persue it.

[QUOTE=MichaelP]Right at the waist, on both sides of the top I had spots 1/2" wide and about 1" long that no mater what I did the finish (ktm9) would not build.[/QUOTE]
Michael,
What a pain! Thanks for the tip in case I have the same trouble.
The location you mention above, is that a place that you tend to hold on to the guitar with your thumb? I know I tend to grab the guitar there and it is about the size of a nice thumb print. There are so many things that could cause this.
Do you rubber gloves? Gloves often have powder or release agents that will cause this type of reaction. They also have have other additives to make them soft that can contaminate. I had a product that I was working on. The supplier changed glove manufacturers without telling us and it caused silicone to not cure. The problem was that the gloves had a small amount of sulfur that would contaminate the silicone.

I'd bet is has something to do with where your thumb was.
You do the best you can to raise them, you just never know how they'll turn out.

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"An adventure is only an inconvenience rightly considered. An inconvenience is an adventure wrongly considered." G. K. Chesterton.