Feelings ( slamming backchecks)

[Newton Hunt]

Hello Ed,

I feel that thump and grind.
I feel compelled to expound.
I feel. . .

Talk a feeling a can of worms! Or was that feeding a can. . .

Very likely this problem is hard leather or hard felt under the
leather.  The leather provides the hold and the felt provide the quiet
and the cushion from that thump.

If the grain of the leather is the wrong way it will make a definite
chunch because the tail is rubbing it the wrong way.  Try that with
the shop cat!  (With leather gloves on!)

The radius of the tail should be 3" to 4" so it provides a wedging
effect against the leather.  Too short a radius causes the tail to
bounce out of check and too long a radius allows the tail to fall
through checking too often, or too deep on a hard blow.

If the tail is too smooth it checks poorly and if it is too rough it
eats leather like my dog did when she could get it.  I like to use an
80 grit sandpaper file to rough he tails or a 50 grit on the disk
sander.

Here is where friction is our friend instead of our enemy.  Too little
friction in the hammer flange and in the wippen post ALlow the hammer
to return to fast and can contribute to noise a back lash.

If this is a problem for the customer then I would change one
backcheck to see if that makes a difference.

Take care and have a good weekend.

		Newton