RE: Terry Blake gap Maximum power?

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Jim Mora" <jmora@xxxxxxxxxxx>

Hi Stan,

I had a single blown gap(5hp compressor) that sounded like a chain saw to
quote Richard Quick who said it would. But it worked great. Just two 1"
brass dowels on threaded legs to solid standoffs... I wonder what a tungsten
faced job would do. I was getting 6' with two 15/60's. 8" coil. LTR .03

I wonder if that teletype motor would turn, a smallish disk? Its rated
1/40th HP which is traditionally underated in those days.

I could have my cousin maybe put roller bearings in it and clean and true it
up..get the fiction to a minimum. He has an alternator, starter business.
How about it Bob, this was a classic find?

Thanks for the info,
Jim Mora

-----Original Message-----
From: Tesla list [mailto:tesla@xxxxxxxxxx]
Sent: Friday, October 06, 2006 6:25 PM
To: tesla@xxxxxxxxxx
Subject: Re: Terry Blake gap Maximum power?

Original poster: Stan <wsmg@xxxxxxxxxx>

Hey Jim,
My first sync gap is a motor similar to yours with 3/32" tig
tungstens running on 2-12/30's with 3-18 to 21 942's mmc banks on a
530 turn 20ga wire  on a 3.5" x  20"  form. The 3/32 tungstens were a
little light, I then went with 7/32 which helped. Don't get
discouraged when you get to running your sync gap it takes awhile to
get them in sync and also tune your primary. I'm running a dc
propeller gap with 1/4" tungstens with a 7kva bombarder on a 9"
coil  and as long as I'm in tune it handles 20 minute to 1/2 hour
runs and probably more getting around 12' arcs**** yea baby****. I powered
up the 3.5"
coil with the bombarder and propeller and the mmc's limited at 3-5
amps and it was throughing 42" arcs, with the small sync I was only
getting 36" with the nsts on a good day otherwise 30".When I ran a
static gap I would get 36" all the time. You might have to experiment
with your run capacitor to get it to sync good with the size of
electrode you use.

Hope this helps
Stan

Tesla list wrote:

>Original poster: "Lau, Gary" <Gary.Lau@xxxxxx>
>
>I assume you're referring to Terry's "propeller gap" configuration?  My
>experience with such a gap goes only as far as using with a 15/60 NST,
>though I know that Terry has used it with at least a PT.
>
>I don't think that the motor size directly limits the power that such a
>gap can be used with.  It's more the diameter of the tungsten rod
>"propeller" and the ability to accommodate temperature rise in the rods
>that determines the maximum power.  I've only seen propeller gaps use
>5/32" or smaller rods, but I suspect that a much thicker rod could also
>work.  You'd have to try it, maybe reducing the length slightly to
>reduce the rotational mass if it's right on the edge.  And rather than
>using a plastic arbor to hold the rod, use phenolic or G10 to tolerate a
>greater temperature rise.  My synchronous propeller gap may be seen at
>http://www.laushaus.com/tesla/sync_gap.htm.
>
>As far as the motor being able to spin up and synch-lock with a heavy
>rod - I'm not sure that there's any real advantage to using a
>synchronous gap for high powered systems.  Most pig-powered systems seem
>to do better at high break rates with asynchronous RSG's.
>
>One more thing - I'm not even sure that system "power" is the limiting
>thing as much as gap current.  Using a high inductance primary to lower
>the gap current will probably result in cooler operation and higher
>efficiency.
>
>Regards, Gary Lau
>MA, USA
>
> > Original poster: "Jim Mora" <jmora@xxxxxxxxxxx>
> >
> > Hi All,
> >
> > I finally found a Classic Teletype 3600 R/PM teletype motor.
> > Nostalgic for me because, to date myself, because I used to work on
> > Teletypes when I was young. How much power do you run through these
>gaps?
> >
> > Thanks,
> > Jim Mora
> >
>
>