Back-Action Traveling

Ron Nossaman RNossaman@KSCABLE.com
Tue, 20 Mar 2001 19:08:54 -0600


>Is this unusual? What would cause such a motion? How can it be corrected
>short of parts replacement? Thanks for any thoughts.
>
>Terry Farrell


This is exactly what shot my bright idea of rough traveling hammer shanks
by pointing them straight up and shimming them plumb. It assumes that the
pin is square with the parts, which obviously isn't the case. Round up some
toys and try this easy illustration to see for yourself.

Take one (ea) pencil, and clip one (ea) spring type clothes pin to it like
the clothes pin was the damper lever and the pencil was the pin. Square the
clothes pin (CP) up on the pencil. Holding the pencil level with the CP
horizontal, and looking down on the model like you were a damper going for
a ride, rotate the pencil so the CP rises and falls. Observe the travel
path. It will be vertical. Now push one end of the pencil away from you,
keeping it level, so it is no longer parallel to your shoulders. Rotate and
observe the travel path. The CP goes left and right as it goes up and down,
just like that damper lever in the piano. Raise one end of the pencil so
it's no longer level. Rotate and observe. Still looks familiar, doesn't it?
Now clip the CP on the pencil at an angle instead of perpendicular. Now the
CP rocks side to side as it travels up and down as well as sweeping left
and right. Try holding the pencil at any angle you can think of to see what
happens to the motion of the CP as it swings through it's arc of travel.
Repeat as necessary until enlightenment strikes, but don't try to show your
wife when it does. She won't be nearly as interested as you - trust me.

You now know nearly all there is to know about traveling flanged parts.

Traveling music - The end - Fade to black.


Ron N


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