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I have been using KTM 9 for some time now (2+years) I have had no issues with it at all, but last night one of my clients brought back in a guitar I finished for him and delivered about 6 months ago. On the neck directly coinciding and matching shape with grain pores the finished raised in probably 30-40 places forming raised dimples the size of the pores.

This neck was fill prior to finishing and if the dimples had recessed into the pores I would have assumed the pores did not fill. but they raised as if the neck had gassed off.

The real funny thing is I sand back to level and there is no interruption of the finish or tale tale witness circle after sanding like you would expect from trapped gas.

Anyone ever seen this?

Sorry I did not think to take pictures prior to sanding the dimples off.

By the way I don't normally put KTM9 on necks but that is what the client wanted

By the way I have finished a lot of woods with KTM 9 including Mahogany and have never had any real issues more less this one

Maohgany? Yes I did grad-ee-ate grade skool

You OK Michael?  I don't see the error of your ways in the previous post.   Looked perfect to me.

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Waddy

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Sound Clips of most of my guitars

What did you spray on before the ktm-9? Shellac? Or is this an epoxy base?

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

It was filled with Zpoxy. Sealed with a thin coat of 1# shellac then scuffed and sprayed. Same as I do on my bodies, Never had this issue there or on anywhere else.

If it was an adhesion issue I would have thought it would have shown during leveling and polishing. this developed over the last 2 months according to the client.

I does not look like I need to add finish. I will know more tonight. Right now I just cant figure it out.

Looks like an easy enough fix since after I sanded the dimples down there appears to still be finish in place.

Like I said I will know more and I start polish sanding tonight.

On what part of the neck did this appear. Is it an area where the owner's hand would be while playing or holding for long periods?
chris

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Chris Oliver
Infinity Luthiers
...in the shop.

live every minute...

[QUOTE=Chris Oliver] On what part of the neck did this appear. Is it an area where the owner's hand would be while playing or holding for long periods?chris
[/QUOTE]

Of course on the back of the neck. From short of nut all the way to radius of the heel in varying amounts of dimples. Mostly on center of the profile and worse between the 8th to heel.

Sounds to me like the client has some kind of strange disease or acidic sweat. I'll bet he took it swimming!

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Greg
http://garibaldiinstruments.com/

Well it sanded down fine through 1200p I will buff out tonight. I dont think it was caused by external influance because the dimples weredirectly above and exactly the size and shape of the pores boundrys.How knows

I wonder if the epoxy gassed off or something? Very weird Michael...you DO manage to have odd things happen to you, eh?

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

[QUOTE=Don Williams] I wonder if the epoxy gassed off or something? Very weird Michael...you DO manage to have odd things happen to you, eh?[/QUOTE]

I'm thinking that for some reason the ZPoxy did not adhere to the pores. My guess is that it was something in the way it was applied. Perhaps the wipe down prior to adding the ZPoxy created the adhesion issue. It might have forced a contaminant into the pores, or the pores shrunk with a naphtha wipe and expanded during and after the epoxy cured, causing i to release. Maybe the Naphtha or whatever solvent you used was contaminated with wax, or the rag was contaminated with wax, oil or detergent that didn't wash out. It wouldn't take much contaminant to coat the pores.
It strikes me that along with the lack of adhesion, there is a force pushing the ZPoxy out of the pores. I can't imagine what that is other than the pores contracting. Is the client controlling humidity?
Anyways, I'm not trying to point fingers or assign blame. I'm just thinking out loud, hoping that someone might be able to figure this one out. If it is not figured out, it is likely to repeat itself with you or any of us that use ZPoxy on our necks.

One more issue - How do you know it has stopped?

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

I have thought pretty much along the same lines Steve.

But the part am not understanding is if it was an adhesion issue. After I sanded the dimples down I would have expected to find voids in the finish where the dimples where, but there appears to be plenty of film still in place.

Michael,

Maybe some primeval lifeform evolved in the soup of the pores and was trying to emerge

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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

Michael,
How thin is the wood beneath your truss rod channel? Could some chemical on the rod have bled through before finishing? This may cause something as weird as this...
Good luck on the repair.
chris

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Chris Oliver
Infinity Luthiers
...in the shop.

live every minute...

Any idea if the guitar has been through extremes of temperature or humidity?

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53% of all statistics are made up on the spot
http://driftwoodguitars.blogspot.com/

[QUOTE=Chris Oliver] Michael,How thin is the wood beneath your truss rod channel? Could some chemical on the rod have bled through before finishing? This may cause something as weird as this...Good luck on the repair.chris
[/QUOTE]

It is at my standard depth of channel and standard D profile so I doubt this was an issue

[QUOTE=WayneC] Any idea if the guitar has been through extremes of temperature or humidity?[/QUOTE]

It was built here in Odessa Tx average 39-42%rh and lives in College Station Tx average 55-65%rh