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How to Make an Old Guitar Playable Again

John Hall

This story has a beginning because of a friends listing on Ebay, an old martin that needed some work. A friend of mine was looking for an older martin pre 1860 and this looked like a fine candidate. I knew the seller and called him. His assessment of this old girl was spot on. The issues that concerned me the most was the unknown skill level of the previous work.

Stephen Brown of Raleigh NC decided he wanted this as a project.

He made arrangements and upon delivery decided this may be more than he wanted to deal with and sent it to me. When the guitar arrived I did give it a good once over.

  • No tuners
  • Cracked fret board (not uncommon)
  • Bar frets were there but needed some attention
  • Steel strings on this fan braced guitar cause top deformation
  • Many top cracks
  • A stack of bridge plate patches and unknowns
  • Missing fan brace
  • Non original bridge

Once I got the bridge off the real fun started.

As you can see here the bridge patches are out and the real top damage is showing. There was a filler patch from the bridge to the outer rosette ring. Most of the cracks opened from the steam and heat to remove the bridge fire wood.

This is what was under the bridge , and none of this was original. I removed this but cutting a sponge to the rough shape and allowed a night of wet sponge to set on this stack to saturate the plates as well as I could. In the morning I used my heat blanket and control and heated this up. There was a top patch under the bridge that came off easy from the night of soaking. This was a plus for me.

Here is the bridge, and the tools I used. I set the heat to full for about 4 minutes then adjusted the control to VAR and set the temp to 175F. As the heat penetrated the layers I could start working my knives into the joint. I was actually lucky as the top piece that came out allowed me to work the top off the firewood pile. I worked about 1 hr to get this apart. You can see the stack of pieces as they came out. This was the order from the top down. It measured about 3/8 in thick. I got one piece out then one broke and came out in 2. The other piece was spruce.

There wasn't as much damage as I was expecting. The top cracks look much worse than they are. This was just after it got heated. This top had a hump from the steel strings but a clamp and a week to settle back down brought this flat.

Once this dried out I could begin addressing the pressing problems. I was posting this on my facebook page and Kathy Wingert posted. I contacted her for some advice. This repair also gave me a new friend. Kathy was giving and her advice was very helpful. I consulted a number of people about this. In the early part, the top was unstable and that had me concerned. Kathy suggested a though patch. I was lucky that I could do this as the loosened filler allowed me to install a patch without back removal. To get the footprint for this I used some magnets. I also had to replace the lower tone bar as this came out during the heating process.

Here is a picture of the paper and magnets so that I could get a template of the patch. This top was .0625 inch thick at the places I measured and not uncommon for a gut stringed guitar. I personally own a pre 1860 0-27. It was X braced and was about the same thickness.

With the paper taped and magnets in position I could make a tracing for the patch. This should give you an idea of what I did. Then after drawing the lines I could make the template and transfer that to the spruce.

I traced the placement of the bridge and position for the middle fan brace. This was able to be inserted into the guitar. This had to go in before the top crack repairs were made. This took a bit of effort to hold back my enthusiasm. Patience is key for this project. I had spoken to Kathy, David Nichols, Steve Kovachik and Frank Ford. I didn't want to do more harm and I respect these colleagues. I now had a plan of execution to address the needed work. I reglued the tight cracks one at a time and only 1 a day. It took about a week and a half to close them all up and get them secure. The 2 larger cracks did take a cleat under the top. Hide glue was used. I did use urea to help with the tack time. I dry fitted and test clamped each joint as there is not a lot of open time with hide glue. I used magnets on many of the cracks. This was a test and on the actual glue up I had wax paper between the magnets and the top. As the cracks were repaired I was surprised at how stiff the top was getting. I spoke to Kathy and my friend Alex Gray. It was felt that the original patch thickness of .035 may have been more than I needed. All that I needed at this point was a patch to homogenize the top. I actually got the piece out the sound hole as the entire cracks were glued. I thinned this to .020 and put it though the sound hole. I also have to make a hinged caul to fit the patch and glue that in.

This allowed me to glue in the patch and tie the top back together. I needed at this point to make fillers for the open cracks that wouldn't close. I took a top and thinned it to .060 in. I then cut multiple pieces to find ones that fit the open gaps.

This process took about 3 hrs to cut and fit the pieces. My concern wasn't making this look new but to make it playable again. To that I can say all was good.

As you can see I had to make a filler for the hole in the top. As you can see the grain is not running in the same direction but I did skew the grain direction to help in 2 ways. 1 it allows more side grain to glue into the end grain. Also the filler was at an angle in the opposite direction. Once this was glued up the top was as stiff as a new top.

Yes you can see the top cracks but they are all tight and closed. The bridge was made and here you can see that the saddle is straight across. Assured the footprintHere is the bridge and new bridge plate. \dry fit testing the middle fan brace using the magnets to help locate under the top. I also had to notch the brace for the plate. This worked remarkably well.

Here is the bridge and plate. I glued them both in at the same time. To get the fan brace clamped I use some jam sticks and a base off the back braces as I didn't want to rick cracking the back.When the glue dries we can complete the guitar.

The marking on the neck block are upside down CF Martin New York Note that the sides and back are glued with Dentils not a kerfed lining. In the entire guitar plays well and sounds nice. Great projection and decent volume for a small guitar.

Blues Creek Guitars is a CF Martin Authorized Repair Center

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