Re: My first ARSG, or a Dangerous Design?

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Crow Leader by way of Terry Fritz <teslalist-at-qwest-dot-net>" <tesla-at-lists.symmetric-dot-net>

 > Original poster: "Barton B. Anderson by way of Terry Fritz
<teslalist-at-qwest-dot-net>" <classictesla-at-netzero-dot-com>
 >
 > No, but will cause the tungsten to press into the set screw and into the
 > threaded hole applying a "goodly" amount of pressure to the tungsten.
There

with say a 4-40 screw on a 1/8" tungsten rod? You are going to get a
stripped allen wrench before lots of pressure.

 > is no "dig into" the tungsten, but there is definitely pressure. It's nice

This pressure is going to drop if anything slips. The the vibration will go
up, the collar slides towards the edges of the rod and the forces go up even
more. Any slippage makes it useless. Add the force of the opposing side
collar that just creeped away from the center of the motor shaft. Now it's
working to pull the other side off. Unless you bite into the tungsten rod,
you are not locking things in place in a secure way.

 > for adjustments to keep the electrode "unscathed". I've used a set screw
 > setup on a G10/tungsten disk for quite sometime now, and have never had a

Which way were the forces acting in this use?

 > set screw (1/4") or electrode  (.375" x 1.25") come loose.

you don't generally use 1/4" set screws on 1/8" or 5/32" rods. It's not hard
to torque a 1/4" UNC bolt to several thousand pounds. The clamping force of
tiny set screws is way less.

 > Just don't use screw locking adhesives (Loctite, etc.). Electrodes get
hot,
 > thus, set screws get hot. This heat causes adhesives to expand and begin

There are set screws with various plastics inserts wedged into a lenghtwise
slit in the threads. These add a decent amount of friction to keep a loose
screw from unscrewing itself.

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KEN