Tail Arcing

[Nichols]

At 12:51 PM 11/3/2004 -0600, you wrote:
>Terry,
>
>In the situation you describe, I usually remove the hammers and arc with 
>the Spurlock jig.  Either take every other hammer, so you can re-space to 
>the neighbors, or make a mylar tracing of the string grooves.
>
>Why won't your hammer/shank assembly fit in the jig?
>
>At Nashville, Guy Nichols showed a method for doing it without 
>disassembly:  clamp a section of shanks (Spurlock shank clamp or 
>equivalent), and arc with disc sander.  Much quicker, if you're confident 
>in your ability to make a usable arc without sanding away some other part 
>of the action <G>.
>
>Mike
>

Mike, Terry,
   Thanks for the plug. That's been at a bunch of "Rebuilding Skills 
Workshops". It's usually the noisiest dern thing in the room. A little 
sawdusty, too. I can't take credit for the technique, I've just used it and 
taught it and I know of a couple of thousand hammer sets that have nicely 
tailed using that technique. I learned it from Jamie Marks, and can't think 
of a reason to do anything else. Joe G. mentions 40 grit. Good call. I use 
50, also. I prefer an air sander, with 6" disks. I just put two disks 
back-to-back for rigidity and flex, rather than using the rubber backing. 
For a right angle grinder, 4.5" disks work. For a Roto-Zip right angle 
attachment, the disks are smaller, but have holes. Makes it easy to see 
through when running, and gets sawdust out of the way. I carry the Roto-Zip 
in the field, because it only takes a few minutes to straighten out the 
bass tails on an action that was built with the bass tails at an angle. A 
quick reshape, followed by a little twisting, and the bass acts civilized 
again! Spurlock, Jaras, threshold, or home-made clamps work just fine. I do 
the whole set, shank nubs and all, in about five minutes. if you're doing 
the nubs, too, do them first. A gentle downward tapping stroke with the tip 
of the disk until they're flush. At classes, I show how to use a compass 
and a marker to black-out the waste area to be ground off. Set your compass 
to about 2 9/16", and stab the shank at a point where the scribe is riding 
on the top of the hammer. Then draw your arc. If you're right handed, do 
this on the left side of the hammer as you face them from behind. No need 
to remove the shank from the rail. When you black out the waste area, it's 
visible through your safety glasses in the space between hammers, and easy 
to stroke the sander across the tails gently to remove the black area. Do 
that on a few samples per section, and it gives you a nice visual target. 
You'll only do that once, because it's so easy to get a good arc. By the 
way, Mike..... your threshold will protect the whipps, etc. <G> It's kinda 
like a radial arm saw. Amazing what you can do if'n ya ain't skeered.

Enjoy,
Guy