Finished massive repairs to 1951 Martin 0-18! with video

[johnnparchem]

One of my guitar instructors had this guitar on his wall. It was his mom's guitar that he was playing in highschool when one of his buddies ran in (over) with his car. It has probably when a wall hanging for 20 years. He still is strongly attached to the guitar and would like to be able to play it again.

I offered to try and get it playable with the least amount of rework I can do. That is keeping as much of the original guitar, finish, age as possible but still have it be structurally sound.

Amazingly it is not in "that" bad of shape. The major crack on the top is repairable. THere is a small section of the x-brace that lifted cleanly over the crack. The tone bar has completely popped off. Just a thin shim of brace remains. With the large access port the repair to the top should not be difficult to do well.

I want to do a visible repair of the missing and cracked parts of the treble side. That is I would like to replace just missing wood with new wood. I still looking for any good idea to repair the wood but my I dea is to have a thin piece of bent mahogany (1 mm) backing the cracked but existing side. Then replace the missing side piece with a patched that is shaped to match the crack pattern. The patch would end up glued to the end bock, new kerfling and the backing patch under the remaining side and the top.

I will do all of the work with hot hide glue.

Here is where I am starting:

[Danl8]

I thought this should be straightforward and then I saw the second picture. Looks scary! If it were me I would bend a replacement side (partial) and 'splice' it in with long scarf joints, etc. Definitely looks to be worth doing and not overly complicated either. Good luck!

[ruby@magpage.com]

Looks like fun.

There was a recent thread on another guitar forum about making a body with 3 piece sides - in other words, two pieces came of from the neck and went past the waist, and a third piece went around the heel to meet them. The general consensus of the answers were that they all wanted a heel block (which you have) to help with setting the guitar down, but that the joints along the sides could be butt joints as long as they had a backer like the strip up the center of the back. Maybe an inlay of some sort because it might be difficult to get both ends of it to match the existing pieces.

Looks not too difficult to make a duplicate of the other side and work it in. I would glue on the lining - maybe make it bent instead of kerfed - to the top and back leaving it just a hair proud, then make some cauls that would allow clamping across the top, or maybe one of those body holders with wedges to provide pressure. Once the side is glued on, any tiny gap would be covered by the binding.

And with that big hole in the side, it won't be difficult to re-glue the braces and fix the crack.

Take pictures

Ed

[tippie53]

I have done a number of these . I use a thin backer of about .030 thick. this is used as a base strata to glue the side pieces together and inlay the missing area. It is surprisingly strong.
I have 2 guitars in the shop that are not quite this bad. One was carried in WW2 and the other was an ebay find. I will be blogging the repairs soon.
I hope you do like wise it makes a great reference and you can show what did and didn't work. Using a drying glue lite fish or hide glue makes a good glue as they are removable
I am sure you will do well

[thronson]

The buddy must have had his foot on the brake and just barley nicked it, could have been worse... luckily the back and top are okay... good luck... that guitar will get back to making music...

[johnnparchem]

Thanks all, I am starting to mix up some hide glue. I will start the repair tomorrow and I will post my progress.
John, I will repair it like you describe. Also thank you for the words of encouragement.

[ruby@magpage.com]

John helped me do one of these a couple of years ago. The first piece he had me install had the grain going up and down as opposed to in the direction of the side. That way it bends very easily, even without heat, and the final product is a form of plywood with 2 pieces with opposing grain direction - is this right John?

Ed

[Diane Kauffmds]

That's definitely a repair and a half. You learn a lot with a repair like this. It'll be fun.

[johnnparchem]

Thanks all, this is a O-15 not an 18 like I said above. I have the guitar on the bench so it looks like I will need to do a neck reset. I will do some research but I assume the 0-15 has a dovetail joint and I can find a gap a couple of frets below the body join.



The inside is really clean



I was able to get the top aligned. I glued the smallest crack working some hot hide glue in and then clamping. Luckily the the rims are pulling the top together so the joint is tight with no clamps. I am using a clamp on the top to align the two sides of the crack. Easy to get the clamps in!

[tippie53]

yes crossgrained backer to start