Earl Brunner on mon 26 feb 01
First off the voltage on the sewing machine has to match the motor. The
kind of motor you are talking about (swamp cooler) isn't anywhere near
the same size.
But even more of a problem is that the motor is an AC (alternating
current) motor. You cannot run an alternating current motor under
torque at slow speeds (the key part here is UNDER TORQUE) using a
voltage regulator (variable speed foot pedal) without overheating the
motor and running the risk of burning it out.
All commercial electric wheels that I know of, that use a variable speed
foot pedal to control voltage to the motor use DC motors.
You may have a good idea about using the bearings and shaft from the
swamp cooler as a basis for a wheel, but I'm inclined to think you would
have greater success with either a kick wheel design or a motorized
kickwheel design.
AC motors can and have been adapted to this type of use.
Lili Krakowski wrote:
> Long ago we used the p;edals (and I seem to recall motors) used when a
> foot-pedaled sewing machine was converted to electricity. As far as I
> know indusrial sewing machines still have such pedals. Check a big place
> that sells industrial sewing machines. Have no idea about specs.
>
>
>
> On Fri, 23 Feb 2001, Jason Patrick wrote:
>
>
>> Thank you for all of the suggestions you gave about how I could make an
>> electric wheel. I have recently come up with the idea of making a wheel
>> out of parts from an evaporative cooling system. Since I live in Arizona,
>> it won't be very hard to get the parts.
>> I find that the motors are about equal to what is found on a wheel, and
>> the pulley system is perfect. I would like to find and attach a pedal to
>> control the speed like on the Brent wheels that I learned to throw on.
>>
>> Does anyone have any idea how to find one of these variable control pedals?
>> I don't know what they are technically named.
>> Thanks for the help. I have learned a lot from the postings on this board.
>>
>> Thanks,
>> Jason
>>
--
Earl Brunner
http://coyote.accessnv.com/bruec
mailto:bruec@anv.net
Lili Krakowski on mon 26 feb 01
Long ago we used the p;edals (and I seem to recall motors) used when a
foot-pedaled sewing machine was converted to electricity. As far as I
know indusrial sewing machines still have such pedals. Check a big place
that sells industrial sewing machines. Have no idea about specs.
On Fri, 23 Feb 2001, Jason Patrick wrote:
> Thank you for all of the suggestions you gave about how I could make an
> electric wheel. I have recently come up with the idea of making a wheel
> out of parts from an evaporative cooling system. Since I live in Arizona,
> it won't be very hard to get the parts.
> I find that the motors are about equal to what is found on a wheel, and
> the pulley system is perfect. I would like to find and attach a pedal to
> control the speed like on the Brent wheels that I learned to throw on.
>
> Does anyone have any idea how to find one of these variable control pedals?
> I don't know what they are technically named.
> Thanks for the help. I have learned a lot from the postings on this board.
>
> Thanks,
> Jason
>
> ______________________________________________________________________________
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>
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>
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>
Lili Krakowski
Rick Monteverde on tue 27 feb 01
In the 'ya can't win' department:
Free motors - On any given day, you drive around a bit and you can
find a broken washing machine out for heavy item trash pickup. These
things usually fail when the plumbing or electronics parts rot way.
The 1/2 HP electric motors in them are built like tanks and almost
always work just fine. Unfortunately, you can't speed-control them
with a pedal. They have a capacitor start mechanism, and can't be run
under speed as has been mentioned. I got one to run my large plastic
casting centriguge ok, there's enough momentum in it that I can
briefly turn it on and off intermittently to get a low speed. But I'm
sure that's unacceptable for a pottery wheel, even with a big
kickwheel-style mass. :(
It's got to be DC. Industrial suppliers sell DC motors, and eBay has
listings - search "DC motor". Chunky ones 3/4 hp or so tend to be
around $100.
- Rick Monteverde
Honolulu, HI
William Moody on tue 27 feb 01
I have been wondering if you could use a speed control such as the ones you
can buy for routers to control the speed on a home made wheel. I have seen
one for about $40. It says, " Reduces speed electronically without reducing
torque; electronic feedback maintains speed by increasing voltage to motor
as load increases." I saw this in a 'Tool Crib' catalogue.
Subject: Re: pedals for homemade wheels.
> In the 'ya can't win' department:
>
> Free motors - On any given day, you drive around a bit and you can
> find a broken washing machine out for heavy item trash pickup. These
> things usually fail when the plumbing or electronics parts rot way.
> The 1/2 HP electric motors in them are built like tanks and almost
> always work just fine. Unfortunately, you can't speed-control them
> with a pedal. They have a capacitor start mechanism, and can't be run
> under speed as has been mentioned. I got one to run my large plastic
> casting centriguge ok, there's enough momentum in it that I can
> briefly turn it on and off intermittently to get a low speed. But I'm
> sure that's unacceptable for a pottery wheel, even with a big
> kickwheel-style mass. :(
>
> It's got to be DC. Industrial suppliers sell DC motors, and eBay has
> listings - search "DC motor". Chunky ones 3/4 hp or so tend to be
> around $100.
Dennis Mummert on tue 27 feb 01
William;
No - same problem, or, actually, two. Routers are universal motors - that
is, they have brushes and are either shunt or series wound. Universal means
they will run on either DC or AC. The little speed controls they sell for
Dremel tools all the way up to larger 2.5/3 HP routers are actually
pulse-width modulators or peak limiters. All they will do to induction
motors is burn up both the control and the motor. The control usually goes
first.
AC drive controllers are mondo expensive, and commercial pottery wheels
with electronic speed controls are DC motors.
-----Original Message-----
From: Ceramic Arts Discussion List [mailto:CLAYART@LSV.CERAMICS.ORG]On
Behalf Of William Moody
Sent: Tuesday, February 27, 2001 4:42 PM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: pedals for homemade wheels.
I have been wondering if you could use a speed control such as the ones you
can buy for routers to control the speed on a home made wheel. I have seen
one for about $40. It says, " Reduces speed electronically without reducing
torque; electronic feedback maintains speed by increasing voltage to motor
as load increases." I saw this in a 'Tool Crib' catalogue.
Louis Katz on tue 27 feb 01
Rather than write a long description of something I don't fully understand, I will
just put up this warning.
There are different types of motors, some like speed controls, some put up with
them, others FRY on them. You might try hooking your router motor up to a pulley
system, but I doubt it was meant for continuous use.
Buy a D.C . motor that is designed to be variable speed and get a speed controller
or variable voltage source to go with it. Avoid slowing the motor down too far,
use pulleys or a gearbox.
Louis
wondering if you could use a speed control such as the ones you
> can buy for routers to control the speed on a home made wheel. I have seen
> one for about $40. It says, " Reduces speed electronically without reducing
> torque; electronic feedback maintains speed by increasing voltage to motor
> as load increases.
William Moody on wed 28 feb 01
Thanks to all who posted about the use of router controls on homemade
wheels. I should have figured it would be too good to be useful. When you
think about it if anyone could make a cheap, workable home made wheel with
no problem then Soldners wouldn't cost as much as they do. As an aside I
have noticed that Thomas Stuart has a new electric wheel. I had one of their
kickwheels and loved it. Does anyone have any experience with their
electrics?
michael wendt on wed 28 feb 01
Important Note: Router controls work on routers because the routers use
series wound D.C. motors. Don't try to use them on permanent magnet D.C.
motors without a bridge rectifier. Never use them on an A.C. motor.
Regards,
Michael Wendt wendtpot@lewiston.com
You asked:
I have been wondering if you could use a speed control such as the ones you
can buy for routers to control the speed on a home made wheel. I have seen
one for about $40. It says, " Reduces speed electronically without reducing
torque; electronic feedback maintains speed by increasing voltage to motor
as load increases." I saw this in a 'Tool Crib' catalogue.
Subject: Re: pedals for homemade wheels.
Louis Katz on wed 28 feb 01
Thanks for the warning. I should know this about DC from a battery driven
flourescent light we had as a kid with two 30 or 40 volt cells in it.
Louis
Dennis Mummert wrote:
> Better yet, friends, DO NOT mess with DC at all unless you know exactly what
> you're doing. Wheels are built to protect the control electronics and the
> user. DC is absolutely lethal at the voltages and currents involved in
> pottery motors. A 110v AC shock is uncomfortable. A 90V DC shock quite
> often ends in lilies.
>
> -----Original Message-----
> From: Ceramic Arts Discussion List [mailto:CLAYART@LSV.CERAMICS.ORG]On
> Behalf Of Louis Katz
> Sent: Tuesday, February 27, 2001 9:24 PM
> To: CLAYART@LSV.CERAMICS.ORG
> Subject: Re: pedals for homemade wheels.
>
> Buy a D.C . motor that is designed to be variable speed and get a speed
> controller
> or variable voltage source to go with it. Avoid slowing the motor down too
> far,
> use pulleys or a gearbox.
Bruce Girrell on wed 28 feb 01
> DC is absolutely lethal at the voltages and currents involved in
> pottery motors. A 110v AC shock is uncomfortable. A 90V DC shock quite
> often ends in lilies.
Back when AC and DC were vying for public acceptance, Thomas Edison would do
public demonstrations of how dangerous AC power was by electrocuting
animals - from puppies to an elephant - with it. Not exactly politically
correct these days. Problem was, he never tried the same voltage/current
levels of DC with any of his subjects. Tesla's AC won out, but not before
Edison had convinced the State of New York of the effectiveness of killing
with electricity and, hence, the development of the electric chair.
The power available from a pottery wheel motor supply - whether AC or DC -
is certainly capable of killing, especially when you consider that water may
also be involved. Electrical repairs should be left to those who have
trained to do them.
Bruce "how shocking" Girrell
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