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Martin DM1 Acoustic/Electric 6-String - Trainwreck
Presented for repair by Kingston's Music Showcase. Noted on the case says I guess it is his. Kingston's said that the owner would be satisfied for it at least to be a "wall hanger". Apparently the owner stumbled and fell on the guitar in its case, and destroyed the guitar and case. As I studied this at Kingston's, I considered first that I had repaired another guitar in this kind of condition, but that one had less of the pieces. This one had almost all of the pieces. The case had been 'customized' by the owner as had the back of the guitar. This guitar was an instrument that obviously had a great deal of sentimental value to the owner. As I stood and looked it over--pondering the 'fixability', I saw a Tetris game or jigsaw puzzle--and a chance to make a guitar owner's day by actually making a seeming "train-wreck" playable again.

BEFORE (click the photo to enlarge)

AFTER (click the photo to enlarge)

AS RECEIVED 7-15-2015
This is the guitar as received. It was in pretty bad shape as can be seen in the photos--including the case. Lots of miscellaneous pieces, and the entire side broken out of the guitar. A lot of ugly top cracks.

Photo 1 - in pieces

Photo 2 - Wood pieces

Photo 3 - Side broken out

Photo 4 - Wood missing

Photo 5 - Cracks / Wood missing

Photo 6 - Cracks

Photo 7 - Cracks

Photo 8 - Cracks

Photo 9 - Pieces

Photo 10 - Marred surface

Photo 11 - Crack

I had the guitar in my shop for six weeks before I could actually start on it. I happened to be pretty swamped when I took it on. Nonetheless, I started on 8/30 by first starting with the smaller cracks--to stabilize them so they didn't grow into bigger ones. I then worked my way through the various larger cracks, evaluating the logic of each 'next step' for outcome, and for following sequences. This advance planning and forethought ensures a stable and nice looking repair. Before I began, I laid out all pieces and planned my assembly strategy. It was then that I noticed some key pieces of wood missing. A strip along the lower part of the soundboard was missing (about 1/4" wide and 5" long--see Photo #1--just to the right of the face sticker). Also a piece was missing from the soundboard at the bottom edge of the lower bout (see photos #4 and #5 above).

8/30 - Just below the center of the bottom piece of tape you can see the crack and a small scratch angling out to the left. That crack is the one being repaired in this photo. Glued, then drawn together with frog tape to hold it secure while it cures.

8/30 - Large crack to under the right side of the tape is not what was being repaired here. It was a smaller crack to the left under the center of the tape. Easier to see in the photo at left.

8/31 - The side of the broken-out piece had this area where there was cracking and delamination. I worked wood glue into the delaminated areas, and clamped it. It was successful. I will fill in this 'battle scar' when the guitar is together, when I am preparing to put some protective finish on it.

9/1 - Here you can see I started working on the case. Several breaks through the case need repair. I usually fix them one at a time--sometimes two at a time.


Other repairs to case and guitar on 9/2 and 9/3 are not photographed.

9/4 - Began gluing internal detached bracing. Easy to get to with the side out.

9/4 - Same bracing, but just photo'd at a different angle.

9/4 - This photo simply shows the detachment of one of the x-braces. It was detached all the way up to the center of the guitar.

9/4 - Another view of the same brace prior to gluing and clamping.

9/4 - the long X-brace glued and clamped.

9/4 - Same clamping photographed from slightly higher angle.

9/4 - More gluing to breaks in the case bottom.

9/4 - Clamping removed

9/5 - Working late. If you look you can see where the crack is located. This is the one being repaired (see red arrows). The green frog tape pulls the crack closed until the glue sets up.

9/5 - A slightly closer view of the same crack. The clamp at the right of each photo helped to keep the wood platform completely flush.


9/5 - I decided to throw this photo in here to show the progress. When compared to photos 1, 7, and 8 above, you can see that the top is definitely taking on a different look. No more ugly cracks. Coming along nicely.


9/5 - Repair of the case. Bottom re-glued in place. IMPORTANT--when gluing wood, remove all former glues, and sand the interfacing surfaces. This insures a high strength bond between the two wood faces. When clamping, apply even pressure. Too much pressure can distort the wood.

9/5 - After the bottom dried. I glued the top back on. I had to remove the top completely to clean the glue surfaces. But this case will not come apart again. Notice the boards--they spread out the clamping pressure over a broader area. 

9/5 - Yet another view of the top, secured in place while the glue dries. 


9/5 - Her I have re-attached one of the pieces that had broken completely out. I put the arrows on the photo so you can see approximately where the part was separated. When putting something like this back together, it is important to do one or more "dry runs" before actually applying glue, to check the fit and to practice the sequence (you get limited time before the glue begins curing).


9/5 - This is the same repair, where the completely separated piece of top wood was put back in place. This is from the underside--prior to applying cleats.


9/5 - This shows the crack from Photo #11 ("before" photos) above. The crack was filled with dark wood glue to match the mahogany, then clamped and allowed to dry. The clamp was later removed, but no photo of that. It was successful.

9/6 - The bottom was next. It was detached near the neck, and it was time to glue it back in place in preparation for putting the detached side piece in place.

9/7 - To reassemble the side, I had to first insure it fit properly. So I did a "dry run"--fitting everything together without glue. This is one of the trickiest parts of the repair. This is when you find out that one of the earlier efforts didn't fit quite right. However, in this case it was a perfect fit--a testament to a) taking time needed to do it right, and b) doing everything in the correct sequence. Sequence is SO IMPORTANT. Note that the seam is minimal in appearance.


9/7 - Another view of the side which is first secured at the top of the upper bout. Putting it in place, and fixing most of it close to where it will be allows two things: 1) minimizes the evidence of a 'seam', and 2) provides a "hinge point" for the next gluing of EVERTHING.

9/7 - Here you can see that I have done the remaining gluing of the main body. This is tricky. I use a proprietary technique for applying glue to get it on fast, and get the pieces put together before the glue 'skins over' (begins to cure). Wood glue dries quickly, so it is imperative to apply it quickly-especially in such a large area as here, and to get the pieces put together, aligned, and clamped, before the glue begins to cure. I have done this so many times, that my method has become my unique niche in the repair business. 

9/7 - Clamping removed.

9/7 - View of missing wood. This wood was not included with the 'kit' as received.

9/7 -  View of the assembled body. Looking good. Also seen here is the missing piece at the bottom of the lower bout (just above the left side of the blue smiley).

9/8 - Planning to insert a piece in the bottom. Here you see the small piece, already tapered, and with a mirror image of the cut that has to be made. This is where some degree of art comes in. I draw the image on the wood by laying it next to the opening, and simply sketching it.

9/8 -

9/8 - Outer is to correct shape.

9/8 - From edge, you can see the 'feathered' taper. Used my belt sander.


9/8 - Final fit of the patch was with sandpaper.


9/8 - Cutting this patch was obviously a bit more of a challenge, but overall it turned out ok. I will have to fill in the crevices.


9/8 - Done for today (mostly) - I am letting the stain that I applied soak into the grain. Most of it was wiped away. I found that a blend of "Early American" and "Pecan" achieves the right color. The above is the Early American only. May apply pecan later this evening. We'll see. Target completion is 9/11 (Friday).

FINISHED 9/10/2015
I finished the guitar one day ahead of schedule. Considering the condition it was in, this was pretty amazing. The action is just about 1/8" at the 12th fret. Everything works normally, and after playing the finished product, I can see why the owner wanted it put back amazing-sounding Martin! See below photos.