This is a 1996 Martin D-41 (purchased new from Mandolin Bros Staten Island) and a few years ago the binding came loose and I took it to someone for repair. A few weeks ago it let go at the waist and there is shrinkage of the binding so it can not simply be glued back in place. I decided to fix this myself since the last 'professional' did not do a good job and it likely came loose and shrunk due to the lack of glue.
There are a few options where you can cut it, glue it then patch but ideally this should be done at the base of the neck or the tail.
Here is a link and best reference I could find for the repair. It is very complete and in this case described in the link the binding broke when trying to free it from under the neck. I took a different approach and decided to cut it at that point so I had a clean edge to work with for the patch.
Loosen the Binding
The binding was fairly loose between the waist and neck. It lifted easily using an exacto knife until I got close to the heel of the neck.
I scored the binding along the neck and seams close to the neck so it would not pull away any of the wood or other layered bindings as it was cut and lifted from the binding channel.
Prepping for Glue
The channel and back of the binding was fairly clean and I did not want to risk cracking it so I did not scrape the wood binding channel or use glue solvent on the back if the binding. There was little or no old glue here so I skipped it.
Glue and Tape
I used Titebond III with a Stewmac glue applicator to get the glue into the channel. First I placed tape at a portion of the binding that was firmly in place so it would not loosen when the binding was bent to place glue in the gap. Glue was placed in the entire length of the channel. The following steps were used to secure the binding in place:
- Press the binding in place for a few inches.
- Clean the excess glue with wet paper towels then dry paper towels.
- Place painters tape on the side and firmly pull the tape over the corner and on the top to secure. Use thin pieces of tape.
I worked my way from the waist to the neck leaving a small gap at the neck that needs to be filled. I left the tape in place for 24 hours which is the full set time for the Titebond.
I checked with Martin service and they confirmed the 1996 binding is Boltaron which is an ABS plastic. I ordered material from Amazon 1.5mm x 5mm and will get back to this when it arrives.
The gap is small- maybe 1/8 inch.
The binding material dissolves in acetone so the end of a piece shaved thin with a knife then softened in acetone. The soft end is placed in the gap then cut with a single edge razor blade. The material hardens for 24-48 hours before final trimming.
|Softening with acetone|
|Pushing into gap|
The rough edges are trimmed with a single edge razor blade using scotch tape to protect the lacquer on the body. After the smoothing with the razor it is rubbed with 800 wet paper.