Re: My first ARSG, or a Dangerous Design?

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

Original poster: "by way of Terry Fritz <teslalist-at-qwest-dot-net>" <Esondrmn-at-aol-dot-com>

In a message dated 1/23/03 5:56:50 PM Pacific Standard Time, 
tesla-at-pupman-dot-com writes:


>Hi Scott, Dan, Terry B, All,
>
>OK here is some CONSTRUCTIVE criticism. IF there really is a problem of low
>coefficient of friction causing slippage, here is one way it can be easily
>cured:
>1) Push tungsten rod through an externally taper-threaded piece of split
>brass tube, so that the tube is in the middle of the rod. The tube must be
>about 0.5" longer than the width of the hub. Hole in hub should also be
>threaded.
>2) Thread tube with rod in it through hub.
>3) Put a locknut on each end of tube to both lock rod into tube and hold
>tube locked into position in hub.
>4) Balance and Run.
>5) Naturally, all plastic parts subjected to rotational stress must be
>inspected periodically for wear and replaced when wear is observed. This is
>true for HDPE, Nylon, Lexan, or G10.
>
>Without these modifications, even at 15,000 rpm, the tip speed of an 8"
>rotor is  ~524 fps. If the rod did start to slip out, it would impact the
>stationary electrodes before it could leave the hub. While this would most
>likely wipe out the rod, the electrodes, and the hub, it would be less
>dangerous than an airborne disk or tangentially-flying small electrodes.
>The design is very creative and hardly what I would call "makeshift".
>
>Matt D.


Another idea would be to use some locking collars on each side of the 
flying electrode, butted up against the poly block that it is pressed 
into.  I noticed I have some of these in my model airplane hardware 
box.  They have set screws in them for locking and I am sure they are 
available with different size holes in the center (to fit different 
diameter rods).

Ed Sonderman