It has been a little too long since my last update. All sorts of things have been keeping me busy this past month as well as some holdups in the progress. But anyway I am still here and still going at it in my workshop.
So in the last post I made and bent the side bindings and the purflings.
In this post I will cut the dado around the back edge and attach the binding. For that I made an XYZ axis router trammel. This jig is otherwise known as the Fleischman/Stevens binding jig or a Universal Binding jig. It is practically foolproof for doing the binding cut on the back and top of the guitar body. The material I am using – curly maple – will match the end graft.
The Universal Binding jig. I am using a 12 inch lazy susan and 600mm drawer slides for the hardware. The rest is just nuts n bolts n plywood.
The back is not flat and I want the router to cut 90 degrees to the side. So I made a curved donut and glued it to the bottom of the router plate. This allows the router plate to ride the edge of the body all the way around. The router plate and donut I also made from 1/2″ poly sheet. The donut was turned on my lathe.
Here it is all together.
Here the body is clamped in place in the mold. Just one test cut to check the depth and I was ready to go.
The grain run-out is not consistent all the way around in regard to the direction of the router bit so a combination of climbing cuts and regular cuts is used with a final cut moving all around clockwise.
Once the cut is complete I size up the binding. The bindings are cut to size with a sharp chisel.
I used tape to hold everything together once the glue was applied. You can see the I am using purple masking tape. Purple masking tape sold here is the tape that has the least tack. When I do the spruce top a strong tacking tape will pull fibers away so I had to check around for a tape that would hold things together but not pull fibers away when I take it off.
A close up of the glued binding.
After a couple of hours I took the tape off, sharpened up a scraper and made the proud surface flush. The tape method worked well because there are no gaps all the way around.
Back view of the completed binding.
Side view of the completed binding.
I was a little worried cutting up the body with a router bit but the three axis router trammel made this step a simple, clean, no drama cut.