It all began with this William Henry knife scale and the shibuichi beetle body pocket inlay. I had trouble holding the shibuichi beetle in place while I carefully and closely scribed around the base to begin cutting the inlay pocket. I managed to get around that problem with a little superglue
, but that made a small cleanup problem and didn’t solve my 2nd problem of holding the inlay in place in the pocket while I punched around the edges to lock the beetle body into place.
I had seen the above image on The Engraver’s Cafe forum sometime in the distant past, so my dim memory of the hold down fixture which would provide a good, solid hold but not be too much in the way while trying to work around the edges. Unfortunately, I wasn’t able to locate it again (above, recently found and provided by a fellow forumite), so I had to come up with my own version. I’ve tried c-clamps before, but between the twisting and clumsy construction, they were almost impossible to work – and they are so poorly made they just don’t work well.
So, here’s my version (from memory) and adapted to the materials and tools I had on hand.
Oh, by the way, don’t read too much into this highly staged scene. The inlay is just a stooge for purposes of illustration…
The clamp is held on to the jaw of the engraving block with a single screw, so the clamp can be rotated horizontally. So, three degrees of freedom, vertical rotation with the pivot and pressure assembly, horizontal rotation by loosening the single hold down screw, and in/out movement by lengthening the gooseneck hold down.
The strange shape of the clamp base is simply an artifact from a Boeing Surplus aircraft aluminum bar, as is the large hole on the upright portion. You really only need a thick “L” shape for the base.
The pivot and pressure assembly is just a rectangle of stainless steel. The hold down gooseneck is just 1/4 inch diameter brass, forged to a small taper. This gooseneck slides in and out about an inch for greater reach, and is locked in place by the socket head cap screw on the front. The long screw in the back raises and lowers the pivot and pressure assembly, and can generate a surprising amount of pressure. When tight, I can’t move the inlay by hand on the surface of the knife scale.
All the screws are 10-32 socket cap screws, so I only need one allen wrench.
Anyway, that’s my story and I’m sticking to it!
Tom
PS It has occurred to me that making a second pivot and pressure assembly, along with a longer pivot screw, would allow me to gang two goosenecks together for longer inlays….
Thanks for looking!