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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 mostly replace just missing wood with new wood. I am going to fit a 1 mm thick piece of bent mahogany (1 mm) backing the cracked but existing side extending to the endblock. I will then inlay in piece of mahogany shaped to match the crack pattern. The patch would end up glued to the end bock, new kerfling and the backing patch. Does anyone have an idea what stain was used to make the mahogany dark?

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

Here is where started:















With 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. It looks like some one set it up by shaving the bridge. At the high E the saddle was 8.7 mm above the top at the bass E the saddle was 11 over the top. I will need to consider what my target is to get 3 more mm I would need to take about .8 off the back of the heel when resetting the neck. The neck is straight, which is good as there is no truss rod.



The inside is really clean

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http://www.Harvestmoonguitars.com

Looks like a nice project. Sounds like you have a plan. Too bad that much of the original wood is missing.

Brown stain. You just have to experiment with the color on some scrap until you get it right. You could start with a brown stain that's close and adjust it from there, but you'll probably need all the primary colors and black to adjust the color to match. The order of operations at the Martin factory is: stain, grain filler, sanding sealer, lacquer.

Was not a stain. What you see is mostly the product of time and age on both the wood and the nitro. Any color imparted to the wood at Martin would have come from the brown paste pore fill that was used but it was typically applied over a sealer coat to minimize that effect.

The wood has darkened some in reaction to light and the nitro has turned amber. My course of action is typically a bit of Nutmeg Solar-Lux to slightly darken the wood and a medium dark amber toner coat over sealer only on the repair with my airbrush to even out the color the rest of the way and then clear lacquer and buff.

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

That guitar needs a new side. It's a big job, but most likely easier than patching the one as it is. As to the stain and color - well that's the least of its issues, so I'd worry about that when the structural work is done. Even given a can of the original stain, you'd probably never get an exact match because the degree of sanding, the order of application for filler, sealer, lacquer, and other aspects will be slightly different. Best approach is to get the whole thing ready for finish, and then start experimenting with dyes, fillers, finish, etc.

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Cheers,

Frank Ford

FRETS.COM
HomeShopTech
FRETS.NET

You got your work cut out for you that's for sure. Good luck and keep us posted.

Thanks for all of the comments. Replacing a side would be a bit easier, especially because I think I need to reset the neck as well. It may be a bit crazy but I really want to maintain the history of the guitar. It was a traumatic event 20 or so years ago and the guitar has been hanging in my instructors studio ever since. I played around with a some of the wood I removed from the side and I think the guitar was finished with shellac. It softened with alcohol. Does that make sense for a 51 Martin?

Bit by bit I am making progress. I closed the cracks on the top and back and installed cleats to keep them closed. When looking at the pictures keep in mind that I want to maintain the history of the smashed guitar. I hope to cleanly install the veneer, but the old and the new wood will be obvious, maybe even outlined with black fiber purfling.

I made an insert that included a tongue to reinforced the intact but cracked area in the sides and kerfed linings to replace the missing linings and assure a good glue joint to the top and back. I was going to use a 1 mm cross grain strip, but could not find one long enough. Instead I thinned an orphaned side to 1 mm, bent it to shape, installed the kerfed linings then I fitted and glued it into the guitar. It is recessed in about 1.5-2.0 mm to allow me to inlay a mahogany veneer.



A couple of orphaned sides to work with. I pick these up in the sale bins on the various tonewood sites. Often they sell a batch of unlabeled sides cheap



I made a cardboard template for the insert.





I bent the insert to the correct shape. It took a bit to get it to fit in the guitar. Once fitted I installed the linings and some reinforcement strips.









Instead of gluing all at once. I used hot hide glue to glue the tongue inside the cracked area. I made special shaped cauls attached to a spreader clamp to some what gently provide an internal backing. (sorry no pictures). I installed a few small cleats on the top and back to help me set the depth on the insert.

With all of the in place I was able to use hot hide glue to glue the insert onto place.



The small gap is where the back brace comes in. The kerfing was inset to the accommodate the brace.


The neck step is to make the veneer. I traced the shape onto some paper using a pencil to highlight the edge.



I cut out the pattern and spend a bit of time getting it to fit by fitting it to the guitar. When ready I taped the pattern to the inside of the side patch and cut close with a band saw.





It did take a combination of a plane for the top and back edges, chalk, chisels, files and sanding sticks to fit the inlay

.

I spend a few moments to decide how to clamp it, after a trial run I decided on the belt clamp. I used fish glue to give me a bit more time to fuss around. Yes I do work bare foot and in my pajamas, retirement is great!

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http://www.Harvestmoonguitars.com

Well John, that is just plain cool

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Steve Smith
"Music is what feelings sound like"

Truly amazed John! Wizard like repair skills especially for someone who doesn't do a lot of repairs,
Mike

Thanks Steve and Mike,

I will play with the color a bit more. Maybe a little bit of yellow, or less red. This with done with Red Mahogany, tobacco brown and a touch of black.





Here is what I had before the stain (just some naptha)

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http://www.Harvestmoonguitars.com

Looks awesome! Do you think it would help to sand back the finish on the original sides a bit and fade the stain in? I'm finish illiterate, just know enough to finish the guitars I build.
Mike

Thanks Mike, I sanded off all of what I put on yesterday and sanded into the original a bit more. I remixed the dye with less red a and a bit more amber. It is not perfect, but looks ok unless looking right at it. The repair is very solid. The guitar has a clean drum like tap sound.

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http://www.Harvestmoonguitars.com

Hard to believe it is the same guitar. Your instructor is going to be a happy camper!
Mike

Outstanding job, you're a fine craftsman!

Very nice work. I actually like the fact that the repaired area is visible. Great provenance.

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Steve Smith
"Music is what feelings sound like"

Thank you guys, I found a clean working set of matching tuners so I should be able to get the guitar strung up this week. I was surprised the the saddle was a bit less than 10 mm above the soundboard and the saddle slot was really shallow. I suspected the bridge was shaved, but after talking to the luthier that wold me the tuners maybe it is in original condition.

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http://www.Harvestmoonguitars.com

I really should let the finish cure for another week or so, but I am not the most patient guy. Here is the 51 all strung up. It is a real instrument again.











from:

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http://www.Harvestmoonguitars.com

Amazing job!

Great Job John!!!

Excellent!

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Steve Smith
"Music is what feelings sound like"

Awesome fix!

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

Heck of a good job John.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Wow!

That is some inspiring and really cool work.

Great! Good job!

Great job.

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michael propsom
www.propsomguitars.com