I had a very difficult time getting The Binding Ledges right. It wasn't the difference in depth, it was the squarenes. It seems like the bottom part of the ledge tilted away from the vertical part at a greater than 90 degree angle. I could not figure it out for the life of me. I even started a thread on here but no one had any ideas. Eventually the only way it worked was by trimming the inside corner of The Binding. Not just the normal amount of breaking the edge but I trimmed about 75% of the bottom. My rabets were an exact fit for my binding, so I didn't have to worry about scraping through too much.

The problem is worst when working the binding rout on a cutaway on the back of the guitar that has a lot of back panel doming and body taper.

The router set-up in that situation looks like this when the router is mounted in vertical axial bearings (drawer slides or similar) which keeps the vertical axis of the router parallel to the plane of the sides.



I can most easily explain the geometry problem by making some analogies. Suppose you cut the binding channel (at the cutaway, approaching the neck, therefore coming down the inclined plane of the back) with a router bit of the same diameter as the binding is thick and the cut was approached at that tilt angle. In that situation, a section through the bottom edge of the rebate would look like this:



That's because of the relative tilt of the flat-ended router bit to the slope of the domed back. It's similar to the half-round groove you would get by dragging a tilted square-ended router bit over a plank.

Now increase the diameter of the router bit and what you get is what I see:



In most cases, the out-of-square is not enough to be troublesome, but in some cases it is.

So, this is an example of great minds thinking alike. There is no doubt the Smith got the patent, although, of course, that doesn't mean that nobody else used the idea before him. There is also no doubt that, in the larger guitar world (or puddle) it was not widely known until Linda came up with it. They both deserve some credit.

This is an example that makes me wonder about the pursuit of credit. Ah the vanity of it all.

Andy

I'd like to clear up something regarding Linda and the wedge body.

When she came up with the wedge as part of the design for the 'Pikasso' guitar Linda had never seen anything like it, so, as far as she was concerned, it was her invention. She didn't try to patent it. At some point around that time she had a conversation with Cumpiano and told him about it. Apparently it slipped his mind. Some time later he had a client who was having right arm problems, and came up with a wedge body as a solution. Having forgotten the conversation with Linda, he claimed it as his invention. This set off a priority debate, until the two of them got together and straightened it out. After that Linda emphasized the idea of the 'Manzer Wedge', not as a way of making money, but simply to claim the priority she felt she had.

Several years ago one of my students did a patent search on guitars, and came up with the Smith patent. I mentioned it on line, and eventually the word got back to Linda, who contacted me. I sent her a copy of the patent, iirc, and we had a cordial exchange. She said that Smith's reasoning was exactly the same as hers.

So, this is an example of great minds thinking alike. There is no doubt the Smith got the patent, although, of course, that doesn't mean that nobody else used the idea before him. There is also no doubt that, in the larger guitar world (or puddle) it was not widely known until Linda came up with it. They both deserve some credit.