On Fri, May 26, 2017 at 2:08 PM,  wrote:

>
> There is one ideal way of doing this,


Well heck, there goes my one great idea.  I was going to suggest visiting
Georgesbasement.com, as I was certain he would have had the answer to this
question.

To the Lumberyard (or Google).... (Young Frankenstein joke)

Do the threads really have to be "that" precise?   Seems to me that most of
the braces I have taken apart have had smaller screws holding the main
screw in place (stop the turning of the pad).  11-1/2 vs 12 should be a
trivial difference.

How about filing a sharp edge on the leading edge of your screw, and just
work it back and forth into an appropriately sized hole in the new pad.  It
is wood, so you can be a little less precise and more aggressive than metal
working or (clock making).
-- 
Kirk Eppler in Half Moon Bay, intrigued by the idea of cutting threads