Re: New testing, more

To: "'Tesla List'" <tesla-at-poodle.pupman-dot-com>
Subject: Re: New testing, more
From: Tesla List <tesla-at-stic-dot-net>
Date: Thu, 11 Sep 1997 22:31:48 -0500
Approved: tesla-at-stic-dot-net

From: 	Malcolm Watts[SMTP:MALCOLM-at-directorate.wnp.ac.nz]
Sent: 	Thursday, September 11, 1997 8:22 PM
To: 	tesla-at-pupman-dot-com
Subject: 	Re: New testing, more

Hi Ed,
        Sorry to hear about your problems....
 
> From:   Esondrmn-at-aol-dot-com[SMTP:Esondrmn-at-aol-dot-com]
> Sent:   Thursday, September 11, 1997 7:10 AM
> To:     tesla-at-pupman-dot-com
> Subject:    New testing, more
> 
> 
> Well, I fired up my coil again tonight after a few months of waiting for the
> replacement Condenser products capacitor.  It arrived a few days ago and was
> installed with a spark gap across it set at about 1.0".  I also recently
> rebuilt my ground system using solid copper flashing to interconnect all the
> ground rods and to the base of the secondary - only maybe 4.0 feet from the
> base of the secondary to the ground system.
> 
> Using a 14.4 kv, 5kva pole pig and a 220 amp lincoln welder with superior
> powerstat for primary power.  I have a switch system set up to switch in
> resistor elements in parallel with the welder.  All switches off is 22 ohms
> in parallel with the welder and all switches on is 3.3 ohms in parallel with
> the welder.  I set the welder on low and the rotary on low speed.
> 
> When I first powered it up, the primary current in to the pole pig was about
> 12 amps.  The gaps would only fire erratically even at full variac voltage.
>  I tried switching in more resistive load in parallel with the welder and the
> gaps almost quit firing altogether with all elements on - about 3.3 ohms.  I
> unplugged the resistive element bank so the welder was on it's own.  As I
> increased the variac voltage, the gaps started firing erratically again and
> the spark gap across the main (.025 mfd) cap started firing.  Someone said
> this would be very loud and they are right, no mistaking if it is firing or
> not.

Did you get any breakout at this point? Discharge to a grounded rod?
 
> I tried different tap settings on the primary and did not have much luck.
>  Still can't get the gaps to fire smoothly.  The coil is trying to tell me
> something and I just don't seem to get it.  I have been having problems with
> this system for the last year, every since I rewired all the primary
> interconnects by replacing the wire (two pieces of RG213 in parallel) with
> 3/8" copper tubing.  This coil used to run very well and has produced 80"
> discharges.
> 
> I thought maybe the RG213 high voltage feed lines to the coil maybe shorting
> internally but I should see high primary current draw if that is the case.  I
> have checked all the primary wiring probably a dozen times and can't find a
> problem.  I am ready to take all the copper tubing back out and rewire all
> the primary interconnects with wire again.  I have three static gaps in
> series with the rotary gap.  The coil originally ran fine with these in the
> circuit and I thought it would help quenching - should I pull them out?  They
> are set at .030" each.

I think it would be a good idea to reduce the gap system to its 
simplest form initially, then add gaps one by one and note the 
effects. I cannot see a single reason why copper pipe should hinder 
any system. To the contrary, it should be close to the best. In 
starting with the system in its most complex form, possibilities for 
unforeseen problems multiply by the number of components.

Keep us posted.
Malcolm

> After I shut the system down for the night, I checked the rotary gap
> carefully and found the gap between the stainless steel acorn nuts on the
> polycarb disc and the fixed (2) tungsten electrodes to be a bit wider than I
> would like.  The disc doesn't run perfectly true so I need a bit more gap
> than I would like.  The total was probably about .150 to .200".  I closed it
> down as close as possible without it hitting.  The total gap now is probably
> .100" plus the three .030 static gaps for maybe .190" total.  Will the system
> be this sensitive to gap distance setting?
> 
> Anyone have any ideas?
> 
> Now I am answering my own post.  This exact set up has now killed two C.P.
> caps.  I can't afford to keep doing this.  Maybe you can have the resistance
> of the primary circuit too low and the cap can't take it.  By the way, the
> primary is 14 turns of 3/8" copper tubing for a total of 84 microheneries.
> 
> Thanks,  Ed Sonderman