From: Chuck Curran [SMTP:ccurran-at-execpc-dot-com]
Sent: Thursday, June 04, 1998 6:32 PM
To: Tesla List
Subject: Re: DC motors
I can't give you a complete answer to your question, for one simple reason.
Since the motor was rated at 0-10,000 RPM my first goal was to limit it's
RPM. I chose to do this by obtaining a 240 VAC to 120 VAC at 10 Amp step
down transformer. I ran 0-120 VAC into the 240 VAC primary and then ran it
through a full wave bridge rectifier and filter cap. The result was around
75 VDC under load which resulted in 3850 RPM checked with a new tachometer.
Since this was 385 bbs with my six moving electrode system, I tried that.
I wanted to get between 350-450 bbs and I was in the ball-park and the
resulting sparks were always around 11 feet with an occasional jump to 13
feet on a real good night. This was at 15-16 Kw input. I still consider
myself "new" at this, so I will freely admit that I didn't try anything
higher or lower. With a limited time to coil I was simply pleased with this
level of success. It has been suggested that certain advantages are
available at exactly 3600 RPM, so if I get the chance I'll try that with the
new coil under construction. Yesterday I got the Delrin I will be using for
the primary support pieces and I plan on going into work and putting the
Bridgeport to use for a bit to get these pieces ready on Saturday. I still
think I might be firing up this new coil by mid July--we will see---
From: Tesla List <tesla-at-pupman-dot-com>
To: 'Tesla List' <tesla-at-pupman-dot-com>
Date: Wednesday, June 03, 1998 9:38 PM
Subject: DC motors
>From: D.C. Cox [SMTP:DR.RESONANCE-at-next-wave-dot-net]
>Sent: Tuesday, June 02, 1998 7:39 PM
>To: Tesla List
>Subject: Re: DC motors
>Curious -- with your coil setup -- what seems to be the best RPM for nice
>bright spark output vs. length? Where does everything seem the "happiest"
>in the systems sparkgap?
>> From: Chuck Curran [SMTP:ccurran-at-execpc-dot-com]
>> Sent: Monday, June 01, 1998 7:31 PM
>> To: Tesla List
>> Subject: Re: DC motors
>> One motor that was mentioned some time ago is available through C and H
>> Sales Company, 1-800-325-9465. I bought this motor, which is a Carter 1
>> H.P., 0-10,000 RPM unit for $50.00. There stock number is DCM9401. It
>> actually a universal motor so you can run it on either AC or DC. I use
>> in my rotary gap with great success on DC. It's full load current draw
>> 10 amps.
>> >From: RODERICK MAXWELL [SMTP:tank-at-magnolia-dot-net]
>> >Sent: Sunday, May 31, 1998 4:32 AM
>> >To: tesla-at-pupman-dot-com
>> >Subject: DC motors
>> >I would like to find a dc motor for for a rotory spark gap. In a
>> >previous post Chip mentioned a company, but I can't remember the address
>> >or phone numbers. I would like a motor that I could smoothly vary the
>> >speed by controlling the voltage with a variac. I want at least one
>> >horsepower, and a maximum speed of 5000rpm.
>> > Frankensteins Helper
>> > Max