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

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




"Jon Elson" wrote in message
...
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 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" wrote in message
...
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

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

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

On Feb 4, 12:38 am, Jon Elson wrote:
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

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

"Jon Elson" wrote in message
...
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

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

On Wed, 03 Feb 2010 23:38:16 -0600, Jon Elson
wrote:

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

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

Gunner

Whenever a Liberal utters the term "Common Sense approach"....grab your
wallet, your ass, and your guns because the sombitch is about to do
something damned nasty to all three of them.