Official Luthiers Forum!
http://www-.luthiersforum.com/forum/

Discoloration on Top, Under Finish
http://www-.luthiersforum.com/forum/viewtopic.php?f=10137&t=49253		 Page 1 of 1
Author:  Ric Hollander [ Sat Apr 15, 2017 4:53 pm ]
Post subject:  Discoloration on Top, Under Finish
Help!

I built this guitar in 2008 and it's been sitting in the case for several years. I took it out a month ago and noticed there is a discoloration (greenish cast) on the spruce top on both edges of the lower bout. Please see the photo below. The finish was perfect on this guitar for years after it was built. The pores were sealed with Z-Poxy and the top was finished with KTM-9.

As an experiment, I had it sitting on a stand in front of a window for several hours today to see if exposure to natural light might help. Maybe it's a tiny bit better, but not sure. It might be wishful thinking. Short of stripping off the hold finish does anyone have any ideas? The neck on this guitar is glued on (I do bolt on now) and I don't want to get get involved in removing it. I'm thinking if I sand off the finish in the affected areas and feather in the finish to the rest of the top there will be witness lines since KTM-9 does not burn in.

I'd really appreciate any ideas anyone might have on how best to fix it. This is the first guitar I built and it sounds and plays beautifully.

Thanks for your help!!!

Ric

Image
Author:  johnparchem [ Sat Apr 15, 2017 5:41 pm ]
Post subject:  Re: Discoloration on Top, Under Finish
Could the greenish cast be in or on top of the finish from where the case felt hit it. I wonder if over time there was some dye transfer. I only mention that as you said both lower bouts and it looks like the felt is green. No Idea with that finish how to fix it.
Author:  truckjohn [ Sat Apr 15, 2017 5:42 pm ]
Post subject:  Re: Discoloration on Top, Under Finish
Any chance the discolored areas were sapwood?
Author:  Tim Mullin [ Sat Apr 15, 2017 6:40 pm ]
Post subject:  Re: Discoloration on Top, Under Finish
Is that by chance a Cedar Creek case?


Sent from my iPad using Tapatalk
Author:  Ric Hollander [ Sat Apr 15, 2017 6:46 pm ]
Post subject:  Re: Discoloration on Top, Under Finish
John - You nailed it! It is present only on the areas where the case touches the guitar, i.e. lower bout edges and back of neck behind the first fret. Any idea how to fix it?

Tim - Yes it is a Cedar Creek case. Have you seen this before?
Author:  Tim Mullin [ Sat Apr 15, 2017 8:00 pm ]
Post subject:  Discoloration on Top, Under Finish
Ric Hollander wrote:
Tim - Yes it is a Cedar Creek case. Have you seen this before?

The green fabric looks familiar. I imported a half-dozen CC cases when I was living in New Zealand in 2009, so same vintage as your guitar. They weren't cheap, but then nothing is in the "land of the long white cloud". Most were tighter than I'd like and all of them stank with fumes that I presumed originated from the adhesive. Different guitars have reacted to contact with the fabric and/or the gassing off of the adhesive. All had the same finish (precat polyester) but the reaction (at least for the three still here) varied with the wood underneath. The fabric "sticks" to the EIR, but the marks are easily polished out. The Ancient Kauri developed a "bloom" over the finish -- again it polished out, but soon returned. I haven't actually had negative feedback from those that went to clients, and the one that's come back for service seems fine. None actually have any colour transfer as you seem to have.
The off-gassing continued for several years with a disagreeable odour, despite several afternoons airing outside with full sunlight. Not my favourite cases.


Sent from my iPad using Tapatalk
Page 1 of 1 All times are UTC - 5 hours
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/