Gibson J-40 conversion

[Ben-Had]

I got this guitar for trade on a $50 repair job I did (came with original Gibson case). I counted about 40 small cracks in the top and there is one on the back and a slight back separation, the tortoise binding had all rotted out and the bridge was cracked as you see it (I removed the PG). I didn't take a pic before I removed the top and routed off the old binding.

I was going to re-top and brace it as a J-40 but after getting the top off I decided I didn't want bracing that heavy on it. Reviews of the J-40 sound are not that resounding and after seeing the bracing I can understand why. I am going to put a sitka top and conventional x-bracing on it.

The current bracing is:

x braces - 5/16 x 1/2
finger - 1/4 x 1/2
transverse - 1/2 x 3/4
top brace - 3/8 x 1/2
bridge plate - 1/8

All that equal (IMO) over-braced.

[Ben-Had]

This guitar was so dried out the back separated and about popped right off. The upper bout braces on the back popped off also. I got them glued back on and cut some new kerfing on my new kerfing jig. The top is also ready to go (post a pic tomorrow). You can also see the multiple hairline splits around the edge of the back I had to shore up.

[Ben-Had]

Got the top, back and binding on.

[Ben-Had]

Decided to remove the old finish and refinish it. I used my Carruth scraper to remove the old finish.

[tippie53]

nice process. thanks for showing. I am looking forward to the progress

[B. Howard]

Looking good.

[ruby@magpage.com]

Tim

Did the braces on the top fit into pockets in the lining/kerfing? If so, how did you get the new braces on the new top properly to fit in the old pockets?

I am faced with a similar job shortly.

Ed Minch

[Ben-Had]

Tim

Did the braces on the top fit into pockets in the lining/kerfing? If so, how did you get the new braces on the new top properly to fit in the old pockets?

I am faced with a similar job shortly.

Ed Minch

No. I cut them out by cutting through the linings in the kerf carefully to the side with a razor saw and then cleaned the new gap and glued in new kerf pieces that were the size of the gaps (each piece was only 2-4 sections long). Then I cut in the new notches like I would on a new build. I cut custom sized pieces to match the old ones.

Edit: The pic above where the kerfing clamps are on is how i did it. Some of the old kerfing was loose and I replaced that as well which is why you see so many clamps on there.

[Ben-Had]

This head stock had the typical Gibson head stock crack. It has been repair and when I am done with the finishing it will be hardly noticeable. On the front side a large piece of wood was missing so I routed the spot clean and square and grafted a new piece in (you can see it sticking out). I will spray the head stock black and it will be invisible. The crack line on the back of the head stock (just below the clamp and from side to side, is also invisible, can't see it in the pic and can't see it up close).

[phavriluk]

Any pictures of the backside of the new top?