Re: Need a variable-speed 2hp or greater AC motor for serious gap drive

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

Original poster: "W.R. Langston by way of Terry Fritz <teslalist-at-qwest-dot-net>" <blangsto-at-iwvisp-dot-com>

Dan,

Funny you should ask. My son, the currently practicing physicist 
(government paid research physicist -- a shade too accustomed to the 
concept of over-engineering IMHO ;-), has machined as close to a 
bulletproof rotary gap as my eyes have ever set on. Somehow he has managed 
to get almost all the people in his section excited about this project and 
directly in on the design and machining work -- if you've ever worked in a 
government lab, that should explain everything about what is going on here.
It looks like it will require 1 1/2 hp to cause this thing to quiver, let 
alone spin. However, once in motion, it should be able to reverse feed 
Hover for a few seconds as it slows down.

If there has ever been something that looked virtually indestructible, this 
is it. Once it is all together, I'll post a photo. One picture is worth a 
thousand poetic phrases. The base and standups are all 1" alloy, the shaft 
is 1" SS round stock. It is electrically isolated (read that "insulating 
belt driven"), and the disc is 1" x12" G11. Last time I looked at the 
design, the electrodes were to present a hemispherical, 1/2" face to each 
other -- set at an appropriately calculated angle to allow for the burn-off 
of early arc and/or late quenching to wear uniformly (I'm betting that part 
of the plan will just never work, what with windage and random heat 
transfer and magnetic field effects on the arc and all).

At any rate, I cannot change his mind to down size the thing, so it fell to 
me to come up with a variable speed control for the 1 phase, 240v, 2 hp 
motor we have now, or a motor and control to suit whatever can get the job 
done.

So, thanks for your input, I'll pass it on to the "team." You see, I am 
over 50 (one foot in the ground already and the other on uncertain 
footing), no longer in an "official" lab... so what do I know -- about 
anything -- in the face of the educated, under thirty crowd????

Oh well, he is my retirement plan, so I guess I'll humor him ;-)

Have a great day,
Bill L.

Tesla list wrote:

>Original poster: "by way of Terry Fritz <teslalist-at-qwest-dot-net>" 
><dhmccauley-at-spacecatlighting-dot-com>
>
>
>If you need one in a hurry, you probably can't be too picky in what you pick
>up used.  Best bet is to check out Grainger-dot-com.
>They have a very large number of universal motors / induction motors from
>the fractional range up to the hundreds of HP.
>
>Why do you need one between 2 and 5 hp for 15-25 kW.  I've typically seen
>less than 1HP universal motors used on 15-25kW sized ARSG.
>Unless you are making a HUUGGGEEE rotor, than i think a 0.5-1.0HP motor
>would suffice.
>
>Dan
>
>
> > Hello folks,
> >
> > Do any of you have a source for either a universal type AC motor of
>between
> > 2 and 5 hp, or a variable speed (chopper-type?) controller usable for a 2+
> > hp induction motor? We need to have built and tested an ASRG for 15-25 kW
> > by July 1st.
> >
> > I suppose a suitable sized, and cool-running DC motor (speed controllable)
> > would work well enough too.
> >
> > We have the machining and structural aspects well enough in hand, but
> > finding a large enough, variable speed motor has proven very difficult.
> >
> > We need to find one or the other asap.
> >
> > Thanks,
> > Bill L.
> >
> >
> >
> >
> >
> >
> >
>
>