Slip ring questions

Guest
I'm sure someone here can help. I need to get power to a solenoid
operated valve spinning at 5000 RPM. Low power, 24 volts at 5 watts.
The power will be on for about 4 seconds and off for 7 seconds. This
on/off cycle will be going on 10 hours a day. I ahve looked at slip
rings online but the high speed through hole type are really spendy.
Then I got to thinking about the slip rings in alternator. They
certainly can carry enough current but I don't know how fast
alternators typically spin. I do have an old alternator that would
make a good slip ring donor. Anybody know or have a better idea? I
need about 1 inch through the slip rings.
Thanks,
Eric
 
If you can, look at an older car's pullies. Look and compare the diameter of the damper pulley with the alternator pulley. You will find it to be quite alot. If the crank is doing 5,000 RPMs, Just look at it.

The problem is finding them. Newer alternators do not do that, they are not "geared" as high so this someting to look into.

You better to get them refit for the time and materials to do the refit.
 
On Tue, 11 Apr 2017 17:15:33 -0700, etpm@whidbey.com wrote:

I'm sure someone here can help. I need to get power to a solenoid
operated valve spinning at 5000 RPM. Low power, 24 volts at 5 watts.
The power will be on for about 4 seconds and off for 7 seconds. This
on/off cycle will be going on 10 hours a day. I ahve looked at slip
rings online but the high speed through hole type are really spendy.
Then I got to thinking about the slip rings in alternator. They
certainly can carry enough current but I don't know how fast
alternators typically spin. I do have an old alternator that would
make a good slip ring donor. Anybody know or have a better idea? I
need about 1 inch through the slip rings.
Thanks,
Eric

Alternator slip-rings (more like graphite brushes) are usually in the
5A-10A range.

...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| STV, Queen Creek, AZ 85142 Skype: skypeanalog | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

Thinking outside the box... producing elegant solutions.
 
On Tue, 11 Apr 2017 17:15:33 -0700, etpm wrote:

I'm sure someone here can help. I need to get power to a solenoid
operated valve spinning at 5000 RPM. Low power, 24 volts at 5 watts. The
power will be on for about 4 seconds and off for 7 seconds. This on/off
cycle will be going on 10 hours a day. I ahve looked at slip rings
online but the high speed through hole type are really spendy. Then I
got to thinking about the slip rings in alternator. They certainly can
carry enough current but I don't know how fast alternators typically
spin. I do have an old alternator that would make a good slip ring
donor. Anybody know or have a better idea? I need about 1 inch through
the slip rings.

I think you'll be good to go. Industrial/military slip rings are
expensive because they go into big expensive machines, which means that
(A) they can be expensive and still be a small part of the whole cost,
(B) if they break then a big expensive machine is broken because of some
little "insignificant" part, and (C) because production volumes are low.
Your alternator slip rings, if you can adapt them, should work fine.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

I'm looking for work -- see my website!
 
On Tue, 11 Apr 2017 17:15:33 -0700, etpm@whidbey.com wrote:

I'm sure someone here can help. I need to get power to a solenoid
operated valve spinning at 5000 RPM. Low power, 24 volts at 5 watts.
The power will be on for about 4 seconds and off for 7 seconds. This
on/off cycle will be going on 10 hours a day. I ahve looked at slip
rings online but the high speed through hole type are really spendy.
Then I got to thinking about the slip rings in alternator. They
certainly can carry enough current but I don't know how fast
alternators typically spin. I do have an old alternator that would
make a good slip ring donor. Anybody know or have a better idea? I
need about 1 inch through the slip rings.
Thanks,
Eric
Slip rings for a car alternator would be fine. Car engines turn in
the thousands of RPM and the alternator is usually run from a pulley
that increases the speed a 2-4X over engine speed.

With motorcycles they turn at engine speed, but then red-line is often
~10,000 RPM or so, and they're fairly easy to take off of the rotor
(just the rings without all the pole pieces coils etc.) They are also
often radial whereas cars have axial slip rings.

The "one inch through" (hole?) might be hard to find on a car
alternator, but would be easy with a bike alternator, or easy to ream
out. The rings are a flat disk with coaxial copper circles imbedded
in some 1/4" thick phenolic and with machine screws into tapped holes
on the rotor pole pieces.

Slip rings may be something you could cobble together if you like to
tinker. Copper tubing or fittings and some epoxy if the temperature
is below a few hundred F. All you have to do is shim it in place
until some epoxy sets. I'd find a way...

A set of radial rings may be possible to fabricate from some printed
circuit board material, if you have access to that sort of gear.
 
In article <4csqeche1q1ss381790ejvnl2vnho4p6oi@4ax.com>,
etpm@whidbey.com says...
I'm sure someone here can help. I need to get power to a solenoid
operated valve spinning at 5000 RPM. Low power, 24 volts at 5 watts.
The power will be on for about 4 seconds and off for 7 seconds. This
on/off cycle will be going on 10 hours a day. I ahve looked at slip
rings online but the high speed through hole type are really spendy.
Then I got to thinking about the slip rings in alternator. They
certainly can carry enough current but I don't know how fast
alternators typically spin. I do have an old alternator that would
make a good slip ring donor. Anybody know or have a better idea? I
need about 1 inch through the slip rings.
Thanks,
Eric

Thinking outside the box. Put a coil of wire on the spinning shaft
connected to the solenoid. Put another coil on the stationary part.
Supply power to the coil and let it transfer like a transformer.
You may even be able to use DC on the stationary coil and let it act
like a generator.
 
On Tue, 11 Apr 2017 23:16:48 -0400, Ralph Mowery
<rmowery28146@earthlink.net> wrote:

In article <4csqeche1q1ss381790ejvnl2vnho4p6oi@4ax.com>,
etpm@whidbey.com says...

I'm sure someone here can help. I need to get power to a solenoid
operated valve spinning at 5000 RPM. Low power, 24 volts at 5 watts.
The power will be on for about 4 seconds and off for 7 seconds. This
on/off cycle will be going on 10 hours a day. I ahve looked at slip
rings online but the high speed through hole type are really spendy.
Then I got to thinking about the slip rings in alternator. They
certainly can carry enough current but I don't know how fast
alternators typically spin. I do have an old alternator that would
make a good slip ring donor. Anybody know or have a better idea? I
need about 1 inch through the slip rings.
Thanks,
Eric

Thinking outside the box. Put a coil of wire on the spinning shaft
connected to the solenoid. Put another coil on the stationary part.
Supply power to the coil and let it transfer like a transformer.
You may even be able to use DC on the stationary coil and let it act
like a generator.

I forget which vehicle had it but there was a brushless alternator
where the coil was stationary and the magnetic field coupled to the
pole pieces to supply a rotating field.

Maybe magnetize the shaft to move something attached to the shaft.
Steel shafting would probably make a semi-permanent magnet, but then
field reversal may work. Assuming centrifugal forces are balanced and
reasonable.

Be nice to know what gizmo he's dealing with. Stepper motors make
decent alternators so it may be possible to generate voltage with the
shaft, but then presumably he still needs a trigger at a specific time
to actuate the solenoid. Maybe do that with some sort of optical
device.

It may also be possible to use something like an electric clutch - a
ring or something that changes position around the axle pushing a rod
and mechanical linkage to move whatever needs moving.

That leads me to think of balancing problems. But even a solenoid
moving will likely result in balance problems at 5,000 RPM.
 
On Wed, 12 Apr 2017 06:43:43 -0400, default <default@defaulter.net>
wrote:

On Tue, 11 Apr 2017 23:16:48 -0400, Ralph Mowery
rmowery28146@earthlink.net> wrote:

In article <4csqeche1q1ss381790ejvnl2vnho4p6oi@4ax.com>,
etpm@whidbey.com says...

I'm sure someone here can help. I need to get power to a solenoid
operated valve spinning at 5000 RPM. Low power, 24 volts at 5 watts.
The power will be on for about 4 seconds and off for 7 seconds. This
on/off cycle will be going on 10 hours a day. I ahve looked at slip
rings online but the high speed through hole type are really spendy.
Then I got to thinking about the slip rings in alternator. They
certainly can carry enough current but I don't know how fast
alternators typically spin. I do have an old alternator that would
make a good slip ring donor. Anybody know or have a better idea? I
need about 1 inch through the slip rings.
Thanks,
Eric

Thinking outside the box. Put a coil of wire on the spinning shaft
connected to the solenoid. Put another coil on the stationary part.
Supply power to the coil and let it transfer like a transformer.
You may even be able to use DC on the stationary coil and let it act
like a generator.

I forget which vehicle had it but there was a brushless alternator
where the coil was stationary and the magnetic field coupled to the
pole pieces to supply a rotating field.

Maybe magnetize the shaft to move something attached to the shaft.
Steel shafting would probably make a semi-permanent magnet, but then
field reversal may work. Assuming centrifugal forces are balanced and
reasonable.

Be nice to know what gizmo he's dealing with. Stepper motors make
decent alternators so it may be possible to generate voltage with the
shaft, but then presumably he still needs a trigger at a specific time
to actuate the solenoid. Maybe do that with some sort of optical
device.

It may also be possible to use something like an electric clutch - a
ring or something that changes position around the axle pushing a rod
and mechanical linkage to move whatever needs moving.

That leads me to think of balancing problems. But even a solenoid
moving will likely result in balance problems at 5,000 RPM.
Thanks everyone for your answers. I now have two options. Get the
rings from my old alternator or use some sort of transformer with a
coil wrapped around the spinning tube coming out of the lathe. Just so
everyone knows what I'm doing I'll describe it now. One of my repeat
jobs is machining an O-ring groove in the underside of a flathead
screw. There is not now a flathead screw available on the market that
has an O-ring groove located in and normal to the angled surface of
the screw head and this is why I am machining these screw heads. A
customer asked me if this could be done and as a consequence I am
doing them. In lots of 2000. Currently the machining time is 7
seconds. The CNC lathe I am running these on has a 15 horsepower
spindle so you can imagine the inertia and energy it takes to start
and stop the spindle. The hydraulic chuck actuator in the lathe will
not work unless the spindle is stopped. I want to keep the spindle
running. I could mount a through spindle air closer that is not
connected to the machine control but it is not and cannot easily be
modified with a dead length feature. Furthermore the top speed is only
3000 rpm and I want 4000 rpm. So to avoid stopping the spindle I am
mounting a dead length collet closer meant for stationary mounting to
the spindle nose of the lathe. I have figured out all the mecahnical
stuff, balancing and all that, and how to get air to the setup. I just
need a good way to power the tiny solenoid operated valve.
Thanks,
Eric
 
On Wed, 12 Apr 2017 09:55:53 -0700, etpm wrote:

On Wed, 12 Apr 2017 06:43:43 -0400, default <default@defaulter.net
wrote:

On Tue, 11 Apr 2017 23:16:48 -0400, Ralph Mowery
rmowery28146@earthlink.net> wrote:

In article <4csqeche1q1ss381790ejvnl2vnho4p6oi@4ax.com>,
etpm@whidbey.com says...

I'm sure someone here can help. I need to get power to a solenoid
operated valve spinning at 5000 RPM. Low power, 24 volts at 5 watts.
The power will be on for about 4 seconds and off for 7 seconds. This
on/off cycle will be going on 10 hours a day. I ahve looked at slip
rings online but the high speed through hole type are really spendy.
Then I got to thinking about the slip rings in alternator. They
certainly can carry enough current but I don't know how fast
alternators typically spin. I do have an old alternator that would
make a good slip ring donor. Anybody know or have a better idea? I
need about 1 inch through the slip rings.
Thanks,
Eric

Thinking outside the box. Put a coil of wire on the spinning shaft
connected to the solenoid. Put another coil on the stationary part.
Supply power to the coil and let it transfer like a transformer. You
may even be able to use DC on the stationary coil and let it act like a
generator.

I forget which vehicle had it but there was a brushless alternator where
the coil was stationary and the magnetic field coupled to the pole
pieces to supply a rotating field.

Maybe magnetize the shaft to move something attached to the shaft. Steel
shafting would probably make a semi-permanent magnet, but then field
reversal may work. Assuming centrifugal forces are balanced and
reasonable.

Be nice to know what gizmo he's dealing with. Stepper motors make
decent alternators so it may be possible to generate voltage with the
shaft, but then presumably he still needs a trigger at a specific time
to actuate the solenoid. Maybe do that with some sort of optical
device.

It may also be possible to use something like an electric clutch - a
ring or something that changes position around the axle pushing a rod
and mechanical linkage to move whatever needs moving.

That leads me to think of balancing problems. But even a solenoid
moving will likely result in balance problems at 5,000 RPM.
Thanks everyone for your answers. I now have two options. Get the rings
from my old alternator or use some sort of transformer with a coil
wrapped around the spinning tube coming out of the lathe. Just so
everyone knows what I'm doing I'll describe it now. One of my repeat
jobs is machining an O-ring groove in the underside of a flathead screw.
There is not now a flathead screw available on the market that has an
O-ring groove located in and normal to the angled surface of the screw
head and this is why I am machining these screw heads. A customer asked
me if this could be done and as a consequence I am doing them. In lots
of 2000. Currently the machining time is 7 seconds. The CNC lathe I am
running these on has a 15 horsepower spindle so you can imagine the
inertia and energy it takes to start and stop the spindle. The hydraulic
chuck actuator in the lathe will not work unless the spindle is
stopped. I want to keep the spindle running. I could mount a through
spindle air closer that is not connected to the machine control but it
is not and cannot easily be modified with a dead length feature.
Furthermore the top speed is only 3000 rpm and I want 4000 rpm. So to
avoid stopping the spindle I am mounting a dead length collet closer
meant for stationary mounting to the spindle nose of the lathe. I have
figured out all the mecahnical stuff, balancing and all that, and how to
get air to the setup. I just need a good way to power the tiny solenoid
operated valve.
Thanks,
Eric

I would be tempted to price out the cost of getting the whole screw made
on a CNC or screw machine, in lots of 10000. If you can break even by
getting 10000 and selling 2000, and if the customer orders often enough,
you can be in cycle where you break even once, make bux four times, break
even once, etc.

Granted, you'd be a salesman for someone else -- but money is money.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

I'm looking for work -- see my website!
 
On Wednesday, April 12, 2017 at 1:27:23 PM UTC-4, Tim Wescott wrote:
On Wed, 12 Apr 2017 09:55:53 -0700, etpm wrote:

On Wed, 12 Apr 2017 06:43:43 -0400, default <default@defaulter.net
wrote:

On Tue, 11 Apr 2017 23:16:48 -0400, Ralph Mowery
rmowery28146@earthlink.net> wrote:

In article <4csqeche1q1ss381790ejvnl2vnho4p6oi@4ax.com>,
etpm@whidbey.com says...

I'm sure someone here can help. I need to get power to a solenoid
operated valve spinning at 5000 RPM. Low power, 24 volts at 5 watts.
The power will be on for about 4 seconds and off for 7 seconds. This
on/off cycle will be going on 10 hours a day. I ahve looked at slip
rings online but the high speed through hole type are really spendy.
Then I got to thinking about the slip rings in alternator. They
certainly can carry enough current but I don't know how fast
alternators typically spin. I do have an old alternator that would
make a good slip ring donor. Anybody know or have a better idea? I
need about 1 inch through the slip rings.
Thanks,
Eric

Thinking outside the box. Put a coil of wire on the spinning shaft
connected to the solenoid. Put another coil on the stationary part.
Supply power to the coil and let it transfer like a transformer. You
may even be able to use DC on the stationary coil and let it act like a
generator.

I forget which vehicle had it but there was a brushless alternator where
the coil was stationary and the magnetic field coupled to the pole
pieces to supply a rotating field.

Maybe magnetize the shaft to move something attached to the shaft. Steel
shafting would probably make a semi-permanent magnet, but then field
reversal may work. Assuming centrifugal forces are balanced and
reasonable.

Be nice to know what gizmo he's dealing with. Stepper motors make
decent alternators so it may be possible to generate voltage with the
shaft, but then presumably he still needs a trigger at a specific time
to actuate the solenoid. Maybe do that with some sort of optical
device.

It may also be possible to use something like an electric clutch - a
ring or something that changes position around the axle pushing a rod
and mechanical linkage to move whatever needs moving.

That leads me to think of balancing problems. But even a solenoid
moving will likely result in balance problems at 5,000 RPM.
Thanks everyone for your answers. I now have two options. Get the rings
from my old alternator or use some sort of transformer with a coil
wrapped around the spinning tube coming out of the lathe. Just so
everyone knows what I'm doing I'll describe it now. One of my repeat
jobs is machining an O-ring groove in the underside of a flathead screw.
There is not now a flathead screw available on the market that has an
O-ring groove located in and normal to the angled surface of the screw
head and this is why I am machining these screw heads. A customer asked
me if this could be done and as a consequence I am doing them. In lots
of 2000. Currently the machining time is 7 seconds. The CNC lathe I am
running these on has a 15 horsepower spindle so you can imagine the
inertia and energy it takes to start and stop the spindle. The hydraulic
chuck actuator in the lathe will not work unless the spindle is
stopped. I want to keep the spindle running. I could mount a through
spindle air closer that is not connected to the machine control but it
is not and cannot easily be modified with a dead length feature.
Furthermore the top speed is only 3000 rpm and I want 4000 rpm. So to
avoid stopping the spindle I am mounting a dead length collet closer
meant for stationary mounting to the spindle nose of the lathe. I have
figured out all the mecahnical stuff, balancing and all that, and how to
get air to the setup. I just need a good way to power the tiny solenoid
operated valve.
Thanks,
Eric

I would be tempted to price out the cost of getting the whole screw made
on a CNC or screw machine, in lots of 10000. If you can break even by
getting 10000 and selling 2000, and if the customer orders often enough,
you can be in cycle where you break even once, make bux four times, break
even once, etc.

Granted, you'd be a salesman for someone else -- but money is money.
I didn't look close but a lot of hits for flat head screw with o-ring seal.
http://www.longlok.com/site/pdf/selfseal.pdf

George H.
--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

I'm looking for work -- see my website!
 
On Wed, 12 Apr 2017 12:27:13 -0500, Tim Wescott
<seemywebsite@myfooter.really> wrote:

On Wed, 12 Apr 2017 09:55:53 -0700, etpm wrote:

On Wed, 12 Apr 2017 06:43:43 -0400, default <default@defaulter.net
wrote:

On Tue, 11 Apr 2017 23:16:48 -0400, Ralph Mowery
rmowery28146@earthlink.net> wrote:

In article <4csqeche1q1ss381790ejvnl2vnho4p6oi@4ax.com>,
etpm@whidbey.com says...

I'm sure someone here can help. I need to get power to a solenoid
operated valve spinning at 5000 RPM. Low power, 24 volts at 5 watts.
The power will be on for about 4 seconds and off for 7 seconds. This
on/off cycle will be going on 10 hours a day. I ahve looked at slip
rings online but the high speed through hole type are really spendy.
Then I got to thinking about the slip rings in alternator. They
certainly can carry enough current but I don't know how fast
alternators typically spin. I do have an old alternator that would
make a good slip ring donor. Anybody know or have a better idea? I
need about 1 inch through the slip rings.
Thanks,
Eric

Thinking outside the box. Put a coil of wire on the spinning shaft
connected to the solenoid. Put another coil on the stationary part.
Supply power to the coil and let it transfer like a transformer. You
may even be able to use DC on the stationary coil and let it act like a
generator.

I forget which vehicle had it but there was a brushless alternator where
the coil was stationary and the magnetic field coupled to the pole
pieces to supply a rotating field.

Maybe magnetize the shaft to move something attached to the shaft. Steel
shafting would probably make a semi-permanent magnet, but then field
reversal may work. Assuming centrifugal forces are balanced and
reasonable.

Be nice to know what gizmo he's dealing with. Stepper motors make
decent alternators so it may be possible to generate voltage with the
shaft, but then presumably he still needs a trigger at a specific time
to actuate the solenoid. Maybe do that with some sort of optical
device.

It may also be possible to use something like an electric clutch - a
ring or something that changes position around the axle pushing a rod
and mechanical linkage to move whatever needs moving.

That leads me to think of balancing problems. But even a solenoid
moving will likely result in balance problems at 5,000 RPM.
Thanks everyone for your answers. I now have two options. Get the rings
from my old alternator or use some sort of transformer with a coil
wrapped around the spinning tube coming out of the lathe. Just so
everyone knows what I'm doing I'll describe it now. One of my repeat
jobs is machining an O-ring groove in the underside of a flathead screw.
There is not now a flathead screw available on the market that has an
O-ring groove located in and normal to the angled surface of the screw
head and this is why I am machining these screw heads. A customer asked
me if this could be done and as a consequence I am doing them. In lots
of 2000. Currently the machining time is 7 seconds. The CNC lathe I am
running these on has a 15 horsepower spindle so you can imagine the
inertia and energy it takes to start and stop the spindle. The hydraulic
chuck actuator in the lathe will not work unless the spindle is
stopped. I want to keep the spindle running. I could mount a through
spindle air closer that is not connected to the machine control but it
is not and cannot easily be modified with a dead length feature.
Furthermore the top speed is only 3000 rpm and I want 4000 rpm. So to
avoid stopping the spindle I am mounting a dead length collet closer
meant for stationary mounting to the spindle nose of the lathe. I have
figured out all the mecahnical stuff, balancing and all that, and how to
get air to the setup. I just need a good way to power the tiny solenoid
operated valve.
Thanks,
Eric

I would be tempted to price out the cost of getting the whole screw made
on a CNC or screw machine, in lots of 10000. If you can break even by
getting 10000 and selling 2000, and if the customer orders often enough,
you can be in cycle where you break even once, make bux four times, break
even once, etc.

Granted, you'd be a salesman for someone else -- but money is money.
I cannot get these made cheaper at 10,000 pieces. Not in the USA that
is. Already been there. But I am thinking about larger quantities.
The screw is headed stamping after threading and the groove has to be
added after heading. The groove cannot be stamped because it is normal
to the head angle. I have been thinking about some way to feed and
load the screws automatically, which is what a screw machine shop
would do. When my customer asked if I could do the job he had only the
desire, no drawing or dimensions. Since I had to do the actual design
and engineering he has no problem with me making these for myself and
selling them to whomever I please. And since the design works so well
because it doesn't require a precise hole diameter and because it
retains the O-ring so securely I think there might be a market big
enough for these to be made in very large quantities.
Eric
 
On 2017-04-12, etpm@whidbey.com <etpm@whidbey.com> wrote:
I'm sure someone here can help. I need to get power to a solenoid
operated valve spinning at 5000 RPM. Low power, 24 volts at 5 watts.
The power will be on for about 4 seconds and off for 7 seconds. This
on/off cycle will be going on 10 hours a day. I ahve looked at slip
rings online but the high speed through hole type are really spendy.
Then I got to thinking about the slip rings in alternator. They
certainly can carry enough current

they only carry a few hundered milliamps, the high current is on the stator.


> but I don't know how fast alternators typically spin.

somewhere 1000 to 4000 RPM I think, same speed as the enine RPM
multiplied by the pulley-size ratio.

I do have an old alternator that would
make a good slip ring donor. Anybody know or have a better idea? I
need about 1 inch through the slip rings.

an automobile altenator shaft is unlikely to be that big,
perhaps use copper pipe and epoxy?


for an automobile 300000 km is about the same as 4 to 8 months run-time
you're using a larger diameter and so that means more
wear but you're only running it 10 hours a day,

maybe it'll last 6 months.


Another option is to put a wound rotor on the shaft and a stator
around it and vary the stator current to control the power generated
in the rotor... this is how brushless altenators feed their main rotor
coil, you want a laminated rotor, maybe from a power tool, or
vacuum-cleaner motor, but bored out to fit the shaft. almost certainly
cost more than slip rings. but frictionless, so should last forever.


--
This email has not been checked by half-arsed antivirus software
 
On Tuesday, April 11, 2017 at 5:13:47 PM UTC-7, et...@whidbey.com wrote:
I'm sure someone here can help. I need to get power to a solenoid
operated valve spinning at 5000 RPM. Low power, 24 volts at 5 watts.

... I need about 1 inch through the slip rings.

It's unlikely that the rings from an auto part will be mechanically adaptable,
but all you need is cylinder (or annulus) elements that spin, and a way to
hold brushes against 'em.

Carbon brushes are available as overpriced repair parts, and as
inexpensive imports, and as parts of every broken power drill.

<http://www.ebay.com/itm/10-PCS-6x10x17mm-Carbon-Brushes-for-Generic-Electric-Motor-GS/322366679902?_trksid=p204http://www.ebay.com/itm/10-PCS-6x10x17mm-Carbon-Brushes-for-Generic-Electric-Motor-GS/322366679902?>

These should make good reliable rubbing contact on bronze, copper, or even brass rotating parts.
It's not uncommon to see assemblies built of linen-based micarta that can hold the low-voltage
elements away from the nearby steel and such; swarf and coolant might be issues, though.
 
On Wed, 12 Apr 2017 11:46:49 -0700 (PDT), George Herold
<gherold@teachspin.com> wrote:

On Wednesday, April 12, 2017 at 1:27:23 PM UTC-4, Tim Wescott wrote:
On Wed, 12 Apr 2017 09:55:53 -0700, etpm wrote:

On Wed, 12 Apr 2017 06:43:43 -0400, default <default@defaulter.net
wrote:

On Tue, 11 Apr 2017 23:16:48 -0400, Ralph Mowery
rmowery28146@earthlink.net> wrote:

In article <4csqeche1q1ss381790ejvnl2vnho4p6oi@4ax.com>,
etpm@whidbey.com says...

I'm sure someone here can help. I need to get power to a solenoid
operated valve spinning at 5000 RPM. Low power, 24 volts at 5 watts.
The power will be on for about 4 seconds and off for 7 seconds. This
on/off cycle will be going on 10 hours a day. I ahve looked at slip
rings online but the high speed through hole type are really spendy.
Then I got to thinking about the slip rings in alternator. They
certainly can carry enough current but I don't know how fast
alternators typically spin. I do have an old alternator that would
make a good slip ring donor. Anybody know or have a better idea? I
need about 1 inch through the slip rings.
Thanks,
Eric

Thinking outside the box. Put a coil of wire on the spinning shaft
connected to the solenoid. Put another coil on the stationary part.
Supply power to the coil and let it transfer like a transformer. You
may even be able to use DC on the stationary coil and let it act like a
generator.

I forget which vehicle had it but there was a brushless alternator where
the coil was stationary and the magnetic field coupled to the pole
pieces to supply a rotating field.

Maybe magnetize the shaft to move something attached to the shaft. Steel
shafting would probably make a semi-permanent magnet, but then field
reversal may work. Assuming centrifugal forces are balanced and
reasonable.

Be nice to know what gizmo he's dealing with. Stepper motors make
decent alternators so it may be possible to generate voltage with the
shaft, but then presumably he still needs a trigger at a specific time
to actuate the solenoid. Maybe do that with some sort of optical
device.

It may also be possible to use something like an electric clutch - a
ring or something that changes position around the axle pushing a rod
and mechanical linkage to move whatever needs moving.

That leads me to think of balancing problems. But even a solenoid
moving will likely result in balance problems at 5,000 RPM.
Thanks everyone for your answers. I now have two options. Get the rings
from my old alternator or use some sort of transformer with a coil
wrapped around the spinning tube coming out of the lathe. Just so
everyone knows what I'm doing I'll describe it now. One of my repeat
jobs is machining an O-ring groove in the underside of a flathead screw.
There is not now a flathead screw available on the market that has an
O-ring groove located in and normal to the angled surface of the screw
head and this is why I am machining these screw heads. A customer asked
me if this could be done and as a consequence I am doing them. In lots
of 2000. Currently the machining time is 7 seconds. The CNC lathe I am
running these on has a 15 horsepower spindle so you can imagine the
inertia and energy it takes to start and stop the spindle. The hydraulic
chuck actuator in the lathe will not work unless the spindle is
stopped. I want to keep the spindle running. I could mount a through
spindle air closer that is not connected to the machine control but it
is not and cannot easily be modified with a dead length feature.
Furthermore the top speed is only 3000 rpm and I want 4000 rpm. So to
avoid stopping the spindle I am mounting a dead length collet closer
meant for stationary mounting to the spindle nose of the lathe. I have
figured out all the mecahnical stuff, balancing and all that, and how to
get air to the setup. I just need a good way to power the tiny solenoid
operated valve.
Thanks,
Eric

I would be tempted to price out the cost of getting the whole screw made
on a CNC or screw machine, in lots of 10000. If you can break even by
getting 10000 and selling 2000, and if the customer orders often enough,
you can be in cycle where you break even once, make bux four times, break
even once, etc.

Granted, you'd be a salesman for someone else -- but money is money.
I didn't look close but a lot of hits for flat head screw with o-ring seal.
http://www.longlok.com/site/pdf/selfseal.pdf

George H.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

I'm looking for work -- see my website!
Greetings George,
Thanks for the link but both my customer and I have seen these screws
and they won't work.
None of those are like what I make and all require a special hole. The
one flat head screw they offer is a 100 degree flat head. Even though
my customer could have a custom 82 degree head made by these folks it
would not seal in the marine industry standard holes. Aircraft
standard holes have less clearance and tighter tolerances. But thanks
again for looking.
Cheers,
Eric
 
In article <4csqeche1q1ss381790ejvnl2vnho4p6oi@4ax.com>,
etpm@whidbey.com says...
I'm sure someone here can help. I need to get power to a solenoid
operated valve spinning at 5000 RPM. Low power, 24 volts at 5 watts.
The power will be on for about 4 seconds and off for 7 seconds. This
on/off cycle will be going on 10 hours a day. I ahve looked at slip
rings online but the high speed through hole type are really spendy.
Then I got to thinking about the slip rings in alternator. They
certainly can carry enough current but I don't know how fast
alternators typically spin. I do have an old alternator that would
make a good slip ring donor. Anybody know or have a better idea? I
need about 1 inch through the slip rings.
Thanks,
Eric

Reading your other replies:

You have a lathe, and that means you have the know how to make
slip rings.

There is no magic to it. Get a short piece of rigget brass pipe of
the size you can deal with and dice off a couple of rings.

Get piece of micarta to make the through hole mounts and pressed form
mounts for the rings.

use set screws to mount on shaft, drill hole in the side of the micarta
for the lead wires and pull tyes to hold them on the shaft or slot the
shaft and lay the wires into that if it needs to go through a bearing
race.

I can usually find short pieces of stock in lock hardware outlets.

if you're cheap you can use construction copper pipe which has a thick
wall./

schedule 40 is ok, 80 is better of course ;)
 
On Wednesday, April 12, 2017 at 5:15:19 PM UTC-4, et...@whidbey.com wrote:
On Wed, 12 Apr 2017 11:46:49 -0700 (PDT), George Herold
gherold@teachspin.com> wrote:

On Wednesday, April 12, 2017 at 1:27:23 PM UTC-4, Tim Wescott wrote:
On Wed, 12 Apr 2017 09:55:53 -0700, etpm wrote:

On Wed, 12 Apr 2017 06:43:43 -0400, default <default@defaulter.net
wrote:

On Tue, 11 Apr 2017 23:16:48 -0400, Ralph Mowery
rmowery28146@earthlink.net> wrote:

In article <4csqeche1q1ss381790ejvnl2vnho4p6oi@4ax.com>,
etpm@whidbey.com says...

I'm sure someone here can help. I need to get power to a solenoid
operated valve spinning at 5000 RPM. Low power, 24 volts at 5 watts.
The power will be on for about 4 seconds and off for 7 seconds. This
on/off cycle will be going on 10 hours a day. I ahve looked at slip
rings online but the high speed through hole type are really spendy.
Then I got to thinking about the slip rings in alternator. They
certainly can carry enough current but I don't know how fast
alternators typically spin. I do have an old alternator that would
make a good slip ring donor. Anybody know or have a better idea? I
need about 1 inch through the slip rings.
Thanks,
Eric

Thinking outside the box. Put a coil of wire on the spinning shaft
connected to the solenoid. Put another coil on the stationary part.
Supply power to the coil and let it transfer like a transformer. You
may even be able to use DC on the stationary coil and let it act like a
generator.

I forget which vehicle had it but there was a brushless alternator where
the coil was stationary and the magnetic field coupled to the pole
pieces to supply a rotating field.

Maybe magnetize the shaft to move something attached to the shaft. Steel
shafting would probably make a semi-permanent magnet, but then field
reversal may work. Assuming centrifugal forces are balanced and
reasonable.

Be nice to know what gizmo he's dealing with. Stepper motors make
decent alternators so it may be possible to generate voltage with the
shaft, but then presumably he still needs a trigger at a specific time
to actuate the solenoid. Maybe do that with some sort of optical
device.

It may also be possible to use something like an electric clutch - a
ring or something that changes position around the axle pushing a rod
and mechanical linkage to move whatever needs moving.

That leads me to think of balancing problems. But even a solenoid
moving will likely result in balance problems at 5,000 RPM.
Thanks everyone for your answers. I now have two options. Get the rings
from my old alternator or use some sort of transformer with a coil
wrapped around the spinning tube coming out of the lathe. Just so
everyone knows what I'm doing I'll describe it now. One of my repeat
jobs is machining an O-ring groove in the underside of a flathead screw.
There is not now a flathead screw available on the market that has an
O-ring groove located in and normal to the angled surface of the screw
head and this is why I am machining these screw heads. A customer asked
me if this could be done and as a consequence I am doing them. In lots
of 2000. Currently the machining time is 7 seconds. The CNC lathe I am
running these on has a 15 horsepower spindle so you can imagine the
inertia and energy it takes to start and stop the spindle. The hydraulic
chuck actuator in the lathe will not work unless the spindle is
stopped. I want to keep the spindle running. I could mount a through
spindle air closer that is not connected to the machine control but it
is not and cannot easily be modified with a dead length feature.
Furthermore the top speed is only 3000 rpm and I want 4000 rpm. So to
avoid stopping the spindle I am mounting a dead length collet closer
meant for stationary mounting to the spindle nose of the lathe. I have
figured out all the mecahnical stuff, balancing and all that, and how to
get air to the setup. I just need a good way to power the tiny solenoid
operated valve.
Thanks,
Eric

I would be tempted to price out the cost of getting the whole screw made
on a CNC or screw machine, in lots of 10000. If you can break even by
getting 10000 and selling 2000, and if the customer orders often enough,
you can be in cycle where you break even once, make bux four times, break
even once, etc.

Granted, you'd be a salesman for someone else -- but money is money.
I didn't look close but a lot of hits for flat head screw with o-ring seal.
http://www.longlok.com/site/pdf/selfseal.pdf

George H.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

I'm looking for work -- see my website!
Greetings George,
Thanks for the link but both my customer and I have seen these screws
and they won't work.
None of those are like what I make and all require a special hole. The
one flat head screw they offer is a 100 degree flat head. Even though
my customer could have a custom 82 degree head made by these folks it
would not seal in the marine industry standard holes. Aircraft
standard holes have less clearance and tighter tolerances. But thanks
again for looking.
Cheers,
Eric

No problems Eric, it took almost no time, so worth what I put into it.

I didn't mean to bother you, (It seems likely there is some screw place,
that could make what you need... just jammin on Tim's idea.)

George H.
 
On Wed, 12 Apr 2017 17:16:23 -0700 (PDT), George Herold
<gherold@teachspin.com> wrote:

On Wednesday, April 12, 2017 at 5:15:19 PM UTC-4, et...@whidbey.com wrote:
On Wed, 12 Apr 2017 11:46:49 -0700 (PDT), George Herold
gherold@teachspin.com> wrote:

On Wednesday, April 12, 2017 at 1:27:23 PM UTC-4, Tim Wescott wrote:
On Wed, 12 Apr 2017 09:55:53 -0700, etpm wrote:

On Wed, 12 Apr 2017 06:43:43 -0400, default <default@defaulter.net
wrote:

On Tue, 11 Apr 2017 23:16:48 -0400, Ralph Mowery
rmowery28146@earthlink.net> wrote:

In article <4csqeche1q1ss381790ejvnl2vnho4p6oi@4ax.com>,
etpm@whidbey.com says...

I'm sure someone here can help. I need to get power to a solenoid
operated valve spinning at 5000 RPM. Low power, 24 volts at 5 watts.
The power will be on for about 4 seconds and off for 7 seconds. This
on/off cycle will be going on 10 hours a day. I ahve looked at slip
rings online but the high speed through hole type are really spendy.
Then I got to thinking about the slip rings in alternator. They
certainly can carry enough current but I don't know how fast
alternators typically spin. I do have an old alternator that would
make a good slip ring donor. Anybody know or have a better idea? I
need about 1 inch through the slip rings.
Thanks,
Eric

Thinking outside the box. Put a coil of wire on the spinning shaft
connected to the solenoid. Put another coil on the stationary part.
Supply power to the coil and let it transfer like a transformer. You
may even be able to use DC on the stationary coil and let it act like a
generator.

I forget which vehicle had it but there was a brushless alternator where
the coil was stationary and the magnetic field coupled to the pole
pieces to supply a rotating field.

Maybe magnetize the shaft to move something attached to the shaft. Steel
shafting would probably make a semi-permanent magnet, but then field
reversal may work. Assuming centrifugal forces are balanced and
reasonable.

Be nice to know what gizmo he's dealing with. Stepper motors make
decent alternators so it may be possible to generate voltage with the
shaft, but then presumably he still needs a trigger at a specific time
to actuate the solenoid. Maybe do that with some sort of optical
device.

It may also be possible to use something like an electric clutch - a
ring or something that changes position around the axle pushing a rod
and mechanical linkage to move whatever needs moving.

That leads me to think of balancing problems. But even a solenoid
moving will likely result in balance problems at 5,000 RPM.
Thanks everyone for your answers. I now have two options. Get the rings
from my old alternator or use some sort of transformer with a coil
wrapped around the spinning tube coming out of the lathe. Just so
everyone knows what I'm doing I'll describe it now. One of my repeat
jobs is machining an O-ring groove in the underside of a flathead screw.
There is not now a flathead screw available on the market that has an
O-ring groove located in and normal to the angled surface of the screw
head and this is why I am machining these screw heads. A customer asked
me if this could be done and as a consequence I am doing them. In lots
of 2000. Currently the machining time is 7 seconds. The CNC lathe I am
running these on has a 15 horsepower spindle so you can imagine the
inertia and energy it takes to start and stop the spindle. The hydraulic
chuck actuator in the lathe will not work unless the spindle is
stopped. I want to keep the spindle running. I could mount a through
spindle air closer that is not connected to the machine control but it
is not and cannot easily be modified with a dead length feature.
Furthermore the top speed is only 3000 rpm and I want 4000 rpm. So to
avoid stopping the spindle I am mounting a dead length collet closer
meant for stationary mounting to the spindle nose of the lathe. I have
figured out all the mecahnical stuff, balancing and all that, and how to
get air to the setup. I just need a good way to power the tiny solenoid
operated valve.
Thanks,
Eric

I would be tempted to price out the cost of getting the whole screw made
on a CNC or screw machine, in lots of 10000. If you can break even by
getting 10000 and selling 2000, and if the customer orders often enough,
you can be in cycle where you break even once, make bux four times, break
even once, etc.

Granted, you'd be a salesman for someone else -- but money is money.
I didn't look close but a lot of hits for flat head screw with o-ring seal.
http://www.longlok.com/site/pdf/selfseal.pdf

George H.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

I'm looking for work -- see my website!
Greetings George,
Thanks for the link but both my customer and I have seen these screws
and they won't work.
None of those are like what I make and all require a special hole. The
one flat head screw they offer is a 100 degree flat head. Even though
my customer could have a custom 82 degree head made by these folks it
would not seal in the marine industry standard holes. Aircraft
standard holes have less clearance and tighter tolerances. But thanks
again for looking.
Cheers,
Eric

No problems Eric, it took almost no time, so worth what I put into it.

I didn't mean to bother you, (It seems likely there is some screw place,
that could make what you need... just jammin on Tim's idea.)

George H.
I wasn't bothered George. Thanks for taking the time. Lots of the time
when I look for something or a solution for something and come up
empty somebody else points out something that I just plain missed. The
way I machine the screws, the location of the O-ring groove, allows
these screws to seal holes with really oversize and corroded holes.
Much of the marine stuff is made with oversized holes to allow easy
assembly of parts with large hole location tolerances as well as
allowing easy disassembly of parts with corrosion products in the
holes.
Cheers,
Eric
 

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