DC motors

From:  Chuck Curran [SMTP:ccurran-at-execpc-dot-com]
Sent:  Thursday, June 04, 1998 6:32 PM
To:  Tesla List
Subject:  Re: DC motors 

Hi D.C.:

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---


-----Original Message-----
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
>to: Chuck
>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
>> Max:
>> 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.
>> Chuck
>> >----------
>> >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
>> >
>> >