Anybody need an air bearing spindle ?

Jon Elson

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Feb 4, 2010, 12:38:16 AM2/4/10

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I just picked up a Professional Instruments
BlockHead 4R air bearing
spindle assembly. It has an integral motor,
resolver, brake and shaft
encoder. It was used in a disk drive development
lab, and currently has a
pneumatically activated clamp for a disk platter
mounted on it.
But, looking at the company web site (still in
business, the 4R is still
a current model) they use these for precision
grinding and other tool
applications, too. It is rated for 10,000 RPM,
and has a radial stiffness of
0.67 Lbs/microinch. I don't know the details of
the motor, whether it is
3-phase induction or PM brushless. It appears to
be unused, as it still
has the factory shipping lock on the spindle.

This is a big unit, seems to weigh about 40 Lbs.
Does anyone have
any use for such an item (before I list it on eBay)?

Jon

Buerste

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Feb 4, 2010, 6:41:19 AM2/4/10

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What do you have in mind? I need a spindle to spin a 6" cut-off disk to
trim End brushes.

"Jon Elson" <el...@pico-systems.com> wrote in message
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Jim Stewart

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Feb 4, 2010, 12:33:23 PM2/4/10

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Buerste wrote:
> What do you have in mind? I need a spindle to spin a 6" cut-off disk to
> trim End brushes.

I think you would be disappointed with the results.
Air bearings need very clean dry air to work and
probably wouldn't be happy with the amount of side
load you'd be applying.

Jon Elson

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Feb 4, 2010, 7:17:50 PM2/4/10

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Jim Stewart wrote:
> Buerste wrote:
>> What do you have in mind? I need a spindle to spin a 6" cut-off disk
>> to trim End brushes.
>
> I think you would be disappointed with the results.
> Air bearings need very clean dry air to work and
> probably wouldn't be happy with the amount of side
> load you'd be applying.

Depending on the air pressure available, I think this unit can sustain a
radial working load of 50 Lbs. Yes, it does need clean dry air, as the
clearances in the bearing are INSANELY small, and you have to keep the
journal from rusting.

Jon

Jon Elson

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Feb 5, 2010, 12:42:20 AM2/5/10

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Buerste wrote:
> What do you have in mind? I need a spindle to spin a 6" cut-off disk to
> trim End brushes.

You can look this up on the Professional
Instruments web site, it is the
4R spindle. See http://www.airbearings.com/4r
for more info. But, the unit I have has quite a
bit more stuff on it, with drive
motor, resolver, brake and shaft encoder. All
these things look like they's
be easy to take off to fit your application. The
business end has a ring
of bolt holes to attach whatever you want on it.
You ought to know this thing
likely cost $30,000 new in the form I have it in.

Jon

oldjag

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Feb 5, 2010, 10:40:52 PM2/5/10

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I might have a use for it. What is the overall length?

Buerste

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Feb 6, 2010, 4:42:02 AM2/6/10

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"Jon Elson" <el...@pico-systems.com> wrote in message

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It sounds like I should pass. I hope somebody needs it "REAL BAD"!

Gunner Asch

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Feb 6, 2010, 9:17:09 PM2/6/10

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On Wed, 03 Feb 2010 23:38:16 -0600, Jon Elson <el...@pico-systems.com>
wrote:

Ping Buerste That would make a great 10k spindle for his project!

Gunner

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