Repair And Restoration
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000-28 w/ neck block shift
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000-28 w/ neck block shift
Im going to attach some photos of a 000-style guitar from Potomac(I believe an Eastman product) that has some top cracks and deformation around the neck block from what I assume to be a shift of the neck block. How do you all approach repairs like this. Im thinking that pulling the neck and somehow pushing the block back into place from the inside is about the right course of action, but if anyone has some advice, Id appreciate it!
In the Photos you can see a close-up of the crack on the treble side of the neck, and equal crack is on the bass side, In the second photo you can see the deformation, especially in the binding.
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8 Replies
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Yes, this you have the right idea. It’s all outlined in Pat’s book. We did it this way on the old Taylors as well. I just found out from Pat yesterday the first printing of the book is sold out, but there will be a second printing. Hopefully these pics will help.
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Can you email me these photos, there turned sideways here and im struggling to make a turnbuckle out of parts from the local hardware store. Does anyone wanna just sell me theirs lol?
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Ted Woodford recently had a YouTube video of a similar repair.
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Pulling the neck would probably be the best move for absolute bullet proofedness. Chances are high that this was put together with some kind of titebond variant and the joint between the top and the neck block have sledded.
If it’s a dovetail, and you pull the neck, you can break that joint and either clean it out and reglue with more titebond (a little dicey), or push everything back into place and reglue with a high grade epoxy (still good to clean it out a little bit, buy you don’t have to be as aggressive as you do with a titebond reglue).
IMO cleating a sledded joint has a chance of recidivism. We’ll everything has a chance of recidivism, but you know.
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So im thinking, heat the area of FB extension, use a putty knife to break as much of the joint between top, block, and braces as I can, then use a spreader against the tail and neck blocks to push things back into position. Once im happy with where it all is, ill get some epoxy into the glue joint previously separated in the extension area, cross my fingers and hold my butt-cheeks tight!
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Man, I’ve been dealing with a lot of this type of thing out here in the desert because of extreme low humidity. If it’s happening on both sides, I would suspect shrinkage of the top. I’m finding that the top, bottom (those areas where wood is much thiner) etc, obviously shrink and warp at a much higher rate then tail/neck blocks. What looks like happens on most of the instruments with this problem is that the top shrinks at a much greater rate then the blocks. Most of the time, not only does the top crack around the neck block, but the tail block as well causing the same type of cracking on both sides of the blocks. I bet dollars to doughnuts that the block hasn’t moved and that the top shrunk and oozed on either side of it. I just dealt with the same situation on a guitar where that area of the rosette came apart. Is the rosette affected as much on the bass side? On the guitar I worked on, the rosette separation was much worse on the treble side. I suspect this was due to the pick guard shrinking in different ways then the surrounding top (as evidenced by the typical crack that forms next to pick guards on many instruments). The rosette on the guitar I fixed was much less complex. Here was the fix: Yes on the neck removal to access that area. I had to do a neck reset anyway, so this was in conjuction to it. First, I super hydrated the body. I took four plastic containers that fit through the sound hole and used fairly damp/just this side of soaked rags rolled up and fit into the containers. I placed them in the upper half of the body and covered the sound hole and bridge pin holes to seal body. I let this sit in place for two weeks, re-dampening the rags every couple of days. This worked amazingly at re-swelling and tightening of that area. In your instance, you may want to remove the pick guard and the inlays of the rosette if possible so as to allow rosette joints to more easily swell into position and to allow for slipping in the next process. The next procedure was the introduction of heat. The idea being that hopefully the top has enlarged, moisture has been added to any glue areas and that when heat is added, any glue areas will slip back into areas we wish to re-align. So, To that end, I pulled the containers and set up cauls and clamps as to where I wanted to apply pressure to re-align and tighten cracks etc. The reason I used heat was that I wanted to hopefully heat glue joints of the braces to allow them to slip as I pulled and pushed the different areas I wanted to move. Tricky because you don’t want the whole thing falling apart! I used a combination of plates, clamps and jacks to pull it off. I put the guitar body on a flat piece of plywood (bottom) using spool clamps in areas to counter pressure where I was using jacks on the inside so as not to separate the side from the top. The plywood on the bottom acts to keep bottom flat against the pressure of the jacks pushing against the bottom. All this was important because I figured that when I applied pressure form the sides and top with clamps to pull the cracks back together, I didn’t want the top to cave or raise out of a flat plane, or the rosette to deform and stay flat. So flat blocks were placed under the bracing around rosette and areas of crack to keep those areas in a flat plane. They were held in place by jacks which were supported by a block laid across the bottom braces.
Then heat was applied to the top in the areas I wanted to push and glue back into shape. I used two heat lamps and heated the top to two hundred degrees. I heated the top for forty five minutes, constantly monitoring with a temp gun to make sure not to overheat. Then I removed heat and clamped flat boards across the top, effectively sandwiching the top into a flat plane, and hopefully pushing the swollen cracked areas back together. I let the whole contraption sit for a week so as to allow the wood to dry out and settle into a new position. I then removed all the clamps, jacks, etc. and…..it worked! All cracks, joints, etc., had tightend up and remained in place. I then used standard repair methods to glue cracks. A lot of work but the results were worth it. I don’t have picks of that guitar but I have picks of a similar repair where I used the same techniques to repair an extreme sunken top around the rosette, causing rosette cracking and shrinkage and belly bulge behind bridge. I was able to successfully flatten the top and swell back into position the shrunk areas around the rosette.
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Further. Ian nailed it with the word “recividism”! Thus the importance of releasing the brace joints. I’ve learned the hard way about this. You go through all the motions of clamping the cracks tight, glue, then put it all back together only to have the thing come apart later. The braces hold everything in position. So when you clamp something where there are braces, your working against the tension of the bracing unless you release that tension. So, I’ve found that you want to release or ease the brace glue joint, then clamp while hot, then let cool in position you want. Much like heating glue joint on a fingerboard to re-bend for relief/back bow. In the case of the Gibson shown in the pics above, the rosette was totally caved in and shrinkage/cracks galore in that area.
Summary: What I’ve found is that if brace glue joints aren’t released, then your working against that memory and tension in that joint. I don’t know the bracing on this guitars but assume there is a side to side brace at least near the end of the finger board extension. In case of the Gibson, there were two small angled cleats around rosette, , on large cleat running side to side between neck block and thick side to side brace. Really hard to pull cracks, rosette problems together and keep them there with all that holding everything in that position. So highly recommend heating to and hopefully allow slippage of bracing/cleats. Of coarse there may be the chance that the area separated from the braces/clamping. If so, great.
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