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Help Needed - repairing finish SNAFU
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Author:  Corky Long [ Sat Apr 03, 2010 12:56 pm ]
Post subject:  Help Needed - repairing finish SNAFU

OK - I'm calm now, but wasn't when I discovered this little gem. Frankly I'm mystified as to how it happened, but there it is - a small chip out of the back of my neck on the guitar that I'm bringing to Newport as part of the Sonic Sitka project. Needless to say, I'm disgusted.

So, is a repair feasible? Finish is KTM-9 water-based lacquer, on top of Z poxy pore filler. The chip looks like it may have taken all the KTM9 - going down to the z poxy. Carefully brush a coat or two of KTM 9 on, let dry and buff back? Either way, I've got a problem with curing time - this guitar needs to be on a plane in 12 days.

Thanks for your help.

Author:  Andy Birko [ Sat Apr 03, 2010 1:07 pm ]
Post subject:  Re: Help Needed - repairing finish SNAFU

It's probably fixable, but not in 12 days. I'm not an expert on that sort of stuff but what I'd do is sand back a larger area so that you don't have a sharp transition at the crack point. Then use an air brush to build up coats of KTM so that it's level. Sand and buff.

(I'm assuming KTM is an infinite melt type of finish).

Author:  Jim Watts [ Sat Apr 03, 2010 4:53 pm ]
Post subject:  Re: Help Needed - repairing finish SNAFU

Corky, While I'm not familar with the KTM finish, With a nitro drop fill I can place a hair dyer about 20 inches away or so and let it blow on it for 24 hrs or so and its ready for leveling and polishing.
I place a thermometer next to the area and try to keep it around 115-120 F or so. Having warm air moving over an evaporative really helps to carry away the volitals.

Author:  Burton LeGeyt [ Sat Apr 03, 2010 5:13 pm ]
Post subject:  Re: Help Needed - repairing finish SNAFU

I am no expert Corky but you could try a quick CA repair to get it ready for the show. Afterwards you could take your time and fix it right. The CA would at least give you a level surface. I would put down a thin KTM level first so the wood is wetted the same and then CA over that before re-levelling and buffing.

Beware that I am only assuming this would work.......

Good luck either way! I am sorry that this happened.

Author:  es guitars [ Sat Apr 03, 2010 7:40 pm ]
Post subject:  Re: Help Needed - repairing finish SNAFU

Corky,

hope this picture makes you feel better. Im doing 2 guitars for the sonic project and have been cursed with nothing but problems. This guitar was for Denis. This happened tuesday. I was ready to string it up.

s**t happens just need to keep going
Brent

Author:  Burton LeGeyt [ Sat Apr 03, 2010 8:42 pm ]
Post subject:  Re: Help Needed - repairing finish SNAFU

Oh man Brent! That is painful to see! :(

Author:  coke_zero [ Sat Apr 03, 2010 8:43 pm ]
Post subject:  Re: Help Needed - repairing finish SNAFU

That's awful I'm gutted for you. I hope both of you are able to find a soultion.

Author:  Mike Lindstrom [ Sat Apr 03, 2010 10:44 pm ]
Post subject:  Re: Help Needed - repairing finish SNAFU

Brent -
What happened?
Mike

Author:  Colin North [ Sun Apr 04, 2010 2:41 am ]
Post subject:  Re: Help Needed - repairing finish SNAFU

Looks like that one failed the run-out test. Boy, that hurts!

Author:  Corky Long [ Sun Apr 04, 2010 11:11 am ]
Post subject:  Re: Help Needed - repairing finish SNAFU

Thanks, all, for the recommendations. Still deciding whether to do anything. I don't want to get into one of those vicious circles where the fix is worse than the original issue. I've certainly been there before.

Brent, I'm really sorry. That's a crushing blow.... and as you said, nothing to be done but keep going. Thanks for sharing. It does help to keep all of this in perspective.

Author:  csullivan [ Mon Apr 05, 2010 12:23 pm ]
Post subject:  Re: Help Needed - repairing finish SNAFU

Hi Corky,
I have fixed small areas on one of my guitars finished with KTM9 with very good success. If you are sure the wood is still covered with epoxy, you should be able to fix this in time for the show. Scuff sand an area with 320 grit larger than the chip so you will get a good mechanical bond between the old and new finish. Use an airbrush and lay on thin coats of KTM9, 3 or 4 coats per day for a couple of days (an hour dry time between coats). Try not to spray outside the area you scuff sanded. Wait a week (you said you have 12 days) and wet sand through the grits you would normally use. Wet sand the new area and out into the old area that is still shiny. My experience was a perfect match and no witness lines. My repair was on a back that was Malaysian blackwood. Any witness lines would have been very noticeable on the dark wood. On your neck, which is lighter, your repair should not show at all. Durability of KTM9 on a neck over time is another matter. It reacts with some people's body chemistry and gets bumpy/pebbly to the touch. I hope this helps.
Craig

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