Cort Semi Hollow

[JimC]

I had a Columbus semi hollow copy back in the 80s that bent like that and kept going out of tune... Felt very guilty about selling it, but I didn't hide that there was a problem. It had no centreblock and I suspected it was the body but had no real idea how to diagnose it. I'm not sure, actually, if I have many more ideas now without a lot of very technical measuring kit. Simon's idea of clamping the neck has a lot going for it... I wonder if you could clamp the body down to a solid surface and have a reference point/scale against the end of the headstock and see how much it bent against a standard load with or without the neck joint clamped.
If it was genuine scrap it would be a good thing to take apart and try and mend because you could learn so much, but seems as if its better than that.

[Sonic Mountain]

Thanks for the replies guys.

I'd be worried about the flexing. It it's an ES-335 it should have a center block so it would not flex any more than an SG or LP...which is to say, not much. Gibson ES-330's did not have center blocks. My experience hollow thinlines is that they are pretty sensitive to temperature and moisture, and go out of tune easily, but they should not have more flex than any other acoustic guitar.

So if there is much flex, there may be some breakage or cracking internally? If the joint has not come a bit loose, then my next guess would be the wood is somehow loosing it's integrity. If that's the case, it might be less work to replace then neck than to fix it.

It definitley has a centre block which appears to be solid from what I can see of it. I am starting to wonder if it's the neck itself due to some extreme heat (as the guitar appears to have been very hot at times) so you may be right that a total replacement might be the best option.

If it's just the neck that's being referred to, then the only real remedy I can think of is to take off the fingerboard and inlay some carbon fibre strengthening either side of the truss rod. Or fit a thicker replacement neck (or maybe a maple rather than mahogany one).

But it does look like there's been movement around the front of the neck joint, so it may not be as tightly glued in as it should be. Which really means neck removal and re-gluing. It's obvious got very hot at some point to bend the plastics that much, and that could have softened the glue enough for string tension to have pulled up the front of the joint slightly.

I suppose you could remove the strings, clamp the joint area and see how bendy the neck is then. If it's a lot firmer, then the joint is to blame. If it's the same, it's just the neck. In which case it's then either living with it (like a lot of SG owners had to with their skinny SG necks), or else going for the strengthening option.

Cheers Simon, you've confirmed my thinking about possible fixes for the neck. I think the next step will be clamping and trying to isolate whether its the neck or the join itself, that's a good idea before I do anything drastic.

I had a Columbus semi hollow copy back in the 80s that bent like that and kept going out of tune... Felt very guilty about selling it, but I didn't hide that there was a problem. It had no centreblock and I suspected it was the body but had no real idea how to diagnose it. I'm not sure, actually, if I have many more ideas now without a lot of very technical measuring kit. Simon's idea of clamping the neck has a lot going for it... I wonder if you could clamp the body down to a solid surface and have a reference point/scale against the end of the headstock and see how much it bent against a standard load with or without the neck joint clamped.
If it was genuine scrap it would be a good thing to take apart and try and mend because you could learn so much, but seems as if its better than that.

Yep, worst case scenario it has good electronics and pickups, so we might be able to salvage some of it. He's coming to pickup a coupel of others I've been working on today so I'll have a chat with him then and keep you all updated.

Thanks again everyone for the input, so good to have you all to bounce this stuff off.

[fender3x]

The body looks really nice, electronics are good. It's definitely worth doing something with!

[Sonic Mountain]

Bit more messing around with the one. So the neck itself definitely flexs if I brace one hand on the heel end and push back on the headstock. I know that this is generally possible with all guitars, but this one does feel a bit softer than you'd expect. I'm not sure that's the whole story tho as if I brace the guitar body and push back on the head stock I can see the whole area here flexing:



The joint it'self looks solid, there's no cracking or anything from the inside and the cracks around the heel on the finish don't appear to move or anything. The finish where the fretboard touches the body is also in good condition with no cracking so I don't think it's moving at the join as such, rather that whole area is flexing.

I've been searching around and came across a few stories of SG's moving as Simon mentioned above, but nothing so far like this.

I think it's either always been like that, or it getting hot at some point has somehow softened the wood. It's pretty odd.

[Woltz]

If it got that hot there is another possible thing that I can think of with these guitars. When you flex the neck does it feel like the back or top shift or move in any way?

I'm wondering whether the sides, back or top are no longer properly adhered to the centre block by the original glue because of the heat exposure.

Sent from my SM-G960F using Tapatalk

[Sonic Mountain]

That was one of my first thoughts when I picked it up and played it, that maybe the centre block had come away. It's very difficult to see in through the F holes, but it looks like it's still glued solidly to the back. But the way it's moving around the neck join is also pretty weird, so if in there is damaged or loose that might make sense. Wish I had one of those little cameras on a probe I could put in and look around with.

Might try with my phone.

EDIT: Got a couple of pics, but its hard to point it in the direction of the neck join, which is the area I'm most interested in. What I can see looks fine, no evidence of it coming away.

[Sonic Mountain]

Ok, so we've had a chat and elected to keep researching options, one of which may be building up a kit using these electronics and putting the kit ones in this so it can be a complete wall hanger.

Does anyone have any idea where I'd find a suitable replacement neck? I can only seem to find them with an offset kind of joint.....

I've floated the idea of putting carbon fibre rods in as well, but obviously that's a bit of a mission and will require nearly as much mucking around finishing as just replacing the neck. I figure if I can get the neck off I can see better if there is anything amiss in the pocket and try and reinforce it as well if needed.

[JimC]

The body movement worries me. Do you have available a known good guitar you can give the same treatment to compare? But cracks in the finish must mean movement has occurred in the past, no way round that. The whole business of putting a damn great hole at the end of the neck for the pickup is structurally dubious for sure.

It seems to me that if the joint has let go on the underside but is still good on top then maybe that would match the symptoms, but I'm just guessing without the experience to make a judgement... I certainly wouldn't trust my opinion on this. You need someone who has seen 335 neck joint failures and can talk with a bit more confidence.

[Sonic Mountain]

Yeah, it's all a bit strange. Cracking at joins isn't all that unusual though and doesn't necessarily mean the joint has failed.

At that end I don't think I'll know the full story until I get go ahead to remove the neck, which may or may not happen, depending on the course of action we decide on.