Guild Jumbo JF55 Neck Split

dlevitan10

Junior Member
Joined
Jul 23, 2020
Messages
12
Reaction score
4
Guild Total
2
There is a split in the finish along the neck seam. Anyone else experience this?
 

gjmalcyon

Senior Member
Gold Supporting
Joined
Feb 6, 2011
Messages
4,181
Reaction score
2,419
Location
Gloucester County, NJ
Guild Total
13
Welcome. Stick around - nice bunch of folks around here. I've never seen that in any my Guilds. Have you checked the truss rod? I can imagine a scenario where an over-tightened truss rod might do that. The guitar is adequately humdified?
 

geoguy

Senior Member
Joined
Mar 1, 2009
Messages
3,519
Reaction score
1,640
Location
metrowest MA
Agreed, with all that gjmalcyon said above.

And I'm sorry that this trouble was what prompted you to join LTG!
 

dlevitan10

Junior Member
Joined
Jul 23, 2020
Messages
12
Reaction score
4
Guild Total
2
Welcome. Stick around - nice bunch of folks around here. I've never seen that in any my Guilds. Have you checked the truss rod? I can imagine a scenario where an over-tightened truss rod might do that. The guitar is adequately humdified?
Thank you for the response. The guitar is about 15-20 years old. Kept in a case but not properly humidified but is now. Does not impact the sound/playability. Seems to be just the finish
 

dlevitan10

Junior Member
Joined
Jul 23, 2020
Messages
12
Reaction score
4
Guild Total
2
Agreed, with all that gjmalcyon said above.

And I'm sorry that this trouble was what prompted you to join LTG!
I should have joined a while ago. I also have a guild D-25M from the mid seventies. Best sounding accoustic I ever played
 

dlevitan10

Junior Member
Joined
Jul 23, 2020
Messages
12
Reaction score
4
Guild Total
2
Funny I don’t see it has a vintage guitar. I guess I am showing my age!
 

gjmalcyon

Senior Member
Gold Supporting
Joined
Feb 6, 2011
Messages
4,181
Reaction score
2,419
Location
Gloucester County, NJ
Guild Total
13
I'm seen that. Don't know why It happens.

Some highly speculative answers:

1). Failure to remove glue squeeze-out at that glue joint, causing the finish adhesion to fail.

2). Differential thermal and/or humidity expansion/contraction rates between the two wood species.

3). Because cosmic rays.
 

GAD

Reverential Morlock
Über-Morlock
Joined
Feb 11, 2009
Messages
22,594
Reaction score
17,815
Location
NJ (The nice part)
Guild Total
112
I asked Hans about a guitar I have with a similar crack and his guess was truss rod over-tightening, so that's my guess.
 

GardMan

Enlightened Member
Joined
Jun 5, 2006
Messages
5,359
Reaction score
959
Location
Utah
Guild Total
5
I think it is POSSIBLE that it is caused by differential expansion/contraction of the different woods due to humidity/temp changes.

OTOH, there were a couple threads years ago regarding these sorts of cracks, particularly in dual-truss rod Guild 12 strings where you sometimes see parallel cracks down the backside of the neck (even a one piece neck) or at the neck joints. IIRC, they were said to be caused by over tightening the truss rods. My recollection of the discussions was that they could be mechanically stabilized by working epoxy into the cracks (maybe thin super glue would also work?) fairly inexpensively, but repairing the finish is would, of course, cost more.
 

chazmo

Super Moderator
Joined
Nov 7, 2007
Messages
25,472
Reaction score
7,131
Location
Central Massachusetts
That is one LOOOONG finish crack. I too suspect truss rod adjustment(s) as the cause. What I've seen before on some of the older 12-strings with dual truss rods are two cracks like that, but never the entire length of the neck like that. Wow. Still, right along the lines of the TR. Anyway, if your guitar is playing OK (playability, that is), I don't think it'd be too difficult to lacquer over this and cover it up. If it isn't, might need to have a neck reset performed on this before trying to fix the finish.
 

davismanLV

Venerated Member
Joined
Mar 24, 2011
Messages
19,201
Reaction score
11,829
Location
U.S.A. : Nevada : Las Vegas
Guild Total
2
I'm kind of stymied on this one. I have seen it before. Of the reasons listed above the one that seems closest to my thinking is the glue squeeze out on the lamination of the neck. Finish will not stick to glue like it will to wood and realize that it could be a combo thing, which the finish doesn't adhere to the glue on the neck joint and then combine that with the truss rod torquing the wood to bend causes the finish to flake off along that seam. Fixing the finish is easier than diagnosing what caused it. Be careful with using polishes or ANYTHING with silicone in it, because once that gets into the crack in the finish, getting finish or glue or anything to stick will be problematic!! That's my best guess at this point. Let's see what else anyone comes up with......

oh and p.s. - welcome to LTG!!
 
Last edited:

dreadnut

Gone But Not Forgotten
Gone But Not Forgotten
Joined
Jun 15, 2005
Messages
16,082
Reaction score
6,442
Location
Grand Rapids, MI
Guild Total
2
Welcome! Seems to me it should be fairly easy to repair, especially as you observed that the crack is not deeper than the finish.

Yeah, we love our old D25's around here. Mine is a '76.
 

dlevitan10

Junior Member
Joined
Jul 23, 2020
Messages
12
Reaction score
4
Guild Total
2
I asked Hans about a guitar I have with a similar crack and his guess was truss rod over-tightening, so that's my guess.
The trust has never needed any adjustment.
Neck is just perfect low action no buzz.
It’s been fine for a very long time.
 

dlevitan10

Junior Member
Joined
Jul 23, 2020
Messages
12
Reaction score
4
Guild Total
2
That is one LOOOONG finish crack. I too suspect truss rod adjustment(s) as the cause. What I've seen before on some of the older 12-strings with dual truss rods are two cracks like that, but never the entire length of the neck like that. Wow. Still, right along the lines of the TR. Anyway, if your guitar is playing OK (playability, that is), I don't think it'd be too difficult to lacquer over this and cover it up. If it isn't, might need to have a neck reset performed on this before trying to fix the finish.
The guitar plays fine and sounds great. To me it’s just finish. In all these years never needed to adjust the trust rod. Neck is stable and plays wells
 

GAD

Reverential Morlock
Über-Morlock
Joined
Feb 11, 2009
Messages
22,594
Reaction score
17,815
Location
NJ (The nice part)
Guild Total
112
The trust has never needed any adjustment.
Neck is just perfect low action no buzz.
It’s been fine for a very long time.


Are you the original owner? Are you saying it spontaneously cracked without any adjustment, or that the crack's been there for a very long time with no apparent ill effect?
 

dlevitan10

Junior Member
Joined
Jul 23, 2020
Messages
12
Reaction score
4
Guild Total
2
Thanks everyone for your quick reply's. To me its just a cosmetic issue. I not rushing to do anything with it. It feels fine to play and the guitar sounds just like it always has. As I mentioned previously in all this time I never needed a set up on the guitar its plays well, no buzzing on the strings, stays in tune, all stuff you want it to do. I think mistake I made is that it was kept in the case and was not humidified. My son had it for several years and never really played. The guitar is now humidified properly and all is good. I guess I will eventually take it to a tech person if I think there is something wrong with the playability but for now all is good. Thanks again to everyone for their thoughful responses.
 

dlevitan10

Junior Member
Joined
Jul 23, 2020
Messages
12
Reaction score
4
Guild Total
2
Are you the original owner? Are you saying it spontaneously cracked without any adjustment, or that the crack's been there for a very long time with no apparent ill effect?
GAD -
I am the original owner bought it new from Rudy's on 47th Street in the City when they were still located there. I am very comfortable doing trust rod adjustments on my guitars and on this one I never needed to do it. It plays fine. It cracked spontaneously.
 

chazmo

Super Moderator
Joined
Nov 7, 2007
Messages
25,472
Reaction score
7,131
Location
Central Massachusetts
Ah, well, so much for the TR adjustment theory! :) Well, very interesting, dlevitan... Glad you cleared that up for us. Well, no idea then. I would take it to a luthier to have a look at it. If you ever find out why that would happen, I would love to hear it. Is it possible that something was in your case that caused this?
 
Top