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Mossman Guitars "Agony of de feet"

Q: Why did the Mossman neck blocks fail?

A: Here's the deal. On the pre-fire guitars the neck block was glued in while the sides were in the mould. It was clamped on with one big clamp that grabbed the block where the bolts come through. The top part of the neck block included "feet" that were designed to connect the fingerboard/top/crossbraces to the neckblock. This put the contact surface of the clamp in the bottom half of the neck block with no clamping on the top. The moulds were made of plywood. The plywood, over the years, compressed so that the top half of the block rocked forward. The back of the guitar is always glued on first because the customer can see through the sound hole and putting the back on first allows you to clean up the glue etc. The tops are glued on blind. When the top was glued on there was as much as a 1/8" gap between the top and the feet. There was nothing wrong with the original design of the block, it was a production error. The various different moulds were variously deformed so some guitars were worse than others and some were fine.

After many experiments, both tried and observed, I have found this to be the best cure for the "agony of de feet" as it was called around the Mossman shop: Remove the fingerboard tongue, route down as far as necessary to contact the whole foot, and then fill with spruce.

The folklore has Mossman guitars collapsing from the weight of their great string length and becoming heart shaped in the upper bout. The truth is that the heart shaped ones were like that when they left the shop. The later neck block designs were an overcorrection of the problem.