Sunday, May 13, 2012

Archtop Guitar Build - Disaster Strikes

Next up was routing the channels for the bindings.  I used a jig that I had built for binding the ukes and I had no problems routing the channel for the top plate.  When I was working on the bottom plate channel, I noticed that the body of the guitar had a lot more resistance to pushing it forward after the bit had passed the neck block.   I pulled the guitar body away and found that the spiral cutting bit had pulled itself forward in the chuck and had routed the channel about 1/8 of an inch too deep!  The side of the body was veneer thin over this channel and had broken though in one area.  I was sick!

When a disaster strikes, the first thing you want to do is fix it quickly but the best thing you can do is to back away and come back another day.  Taking time to think through the problem helps avoid making the problem worse by trying a quick fix.  There were a lot of options available.  My first thought was to fill the bad route with ultra-thin model airplane plywood to stabilize the side, that's the darker brown material in this photo.   I then planned on using matching maple veneer to cover the plywood core but I knew that I would never be happy with this kind of repair.  It was time to gear up for major surgery.

I sawed the back plate off of the guitar and stripped out the linings for this plate.  I then made new linings, installed them and leveled them out.  Here is the body with new lining, placed back in the building mold just before the back plate was glued on.
The new total depth of the body is 2 3/4 inches which is at the low end of acceptable per the Benedetto book.  The only problem is that the end pin hole is now closer to the back plate than to the front but this was a small price to pay for a better repair.  Here is the back plate being glued in place
I then invested in the Stew Mack binding router set-up.  It is very pricey but it works well and I knew that if it saved me from having to go through another major set-back it would be worthwhile.
 The new channels were clean and true.
 Plastic binding was installed on the problematic back plate and this is the end result.

 Here is the front plate with the bone insert for the tail piece strap.


It is nice to be back in business...




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