Re: RSG material?

[FutureT-at-aol-dot-com (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

In a message dated 9/14/00 4:49:38 PM Pacific Daylight Time, tesla-at-pupman-dot-com 
writes:

> Original poster: "Travis Tabbal" <bigboss-at-xmission-dot-com> 
>  
>  
>  Hello list members.                                                   
>                                                                        
>  I am currently attempting to build an SRSG. I have located a motor for
>  modification and will be running 3600 RPM. I gather I need 2          
>  electrodes on the rotor. I see a lot of series gap designs on the net.
>  Is that something I should look into? I would like to shoot for the   
>  120 bps system. Firing every half cycle.          

Travis,

Two electrodes on rotor is correct.  I'm not sure what you mean
by series designs.  Do you mean using 2 gaps in the rotary as
in my designs at? :

  http://hometown.aol-dot-com/futuret/page3.html     

Or something with a greater number of series gaps?  Or do you
mean external static gaps in series with the rotary?               
>                                                                        
>  I would like to gap to handle 5-10 KVA without melting. With runtimes 
>  of 1-2 minutes tops. I was thinking tungsten electrodes (the arc      
>  welder kind).       

Well tungsten is the best for high power use.  You can use a thick 
strong flat steel
solid pulley of some type and drill holes in it to make a hub to hold the
rotor, or have someone machine a hub for you on a lathe which is
preferable.  Other types of phenolic other than G-10 can be used and
are cheaper, but not as strong, but still very strong.  These other types
of phenolics are mentioned in the McMaster Carr catalog, some contain
linen, burlap, paper, etc.  Many folks have gotten good results with
Lexan, but it can soften if it gets too warm/hot.
                                                 
John Freau