I'm copying both the metalworking and woodworking groups. I hope this
doesn't **** anyone off too badly. I believe the answers and knowledge that
may get passed around is mutually beneficial. Thus the breach in newsgroup
etiquette.

Anyhow... I've got a unique problem.

I sell a product that acts basically like an air cylinder. It has a tube
(hard chrome plated inside for you metal guys) with a quill (hard chrome
plated also) and some rubber seals inside.

One of my customers is a medical giant. They can't have ANY type of
lubricant in the cylinder as they run the drill or the FDA comes in and
gives them hell.

So... They basically super-dry their air with a desiccant and dryers so
that it is down to 0.01% humidity or less and use absolutely no oil
whatsoever inside the unit.

After 2-3 years of running like this, the unit doesn't stroke so well. The
seals are dried out and the cylinder, although still sealed properly, needs
up to 80 PSI air to stroke at all. Normally, they stroke at 15 PSI or so...

Anyone know of a lubricant that could be used that would not cause medical
(food grade or better maybe?) issues?

Can't use oil, grease, dry powder stuff, etc. Can't even use water...

I was thinking something like medical grade alcohol or acetone that
disappears all by itself if it gets to the atmosphere... But I bet there is
a better option.

Thoughts?

As a side note, the tube and quill will stroke millions of times with no
lube without wearing out. We've done long-term tests... The tolerances
between quill and tube are around 0.001" and the quill diameter is around 3"
if it matters.

Having just read a bunch of posts about air tools and proper lube made me
think that there might be an expert in here with some ideas...

Regards,
Joe Agro, Jr.
(800) 871-5022
01.908.542.0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com
Production Tapping: http://Production-Tapping-Equipment.com/
Flagship Site: http://www.Drill-N-Tap.com
VIDEOS: http://www.youtube.com/user/autodrill

V8013-R

I see this as a win-win situation, an opportunity to sell them a new
cylinder every couple of years, and charge them $100 per hour
installing said cylinders.

i

Joe AutoDrill wrote:

I'm copying both the metalworking and woodworking groups. I hope this
doesn't **** anyone off too badly. I believe the answers and knowledge that
may get passed around is mutually beneficial. Thus the breach in newsgroup
etiquette.

Anyhow... I've got a unique problem.

I sell a product that acts basically like an air cylinder. It has a tube
(hard chrome plated inside for you metal guys) with a quill (hard chrome
plated also) and some rubber seals inside.

One of my customers is a medical giant. They can't have ANY type of
lubricant in the cylinder as they run the drill or the FDA comes in and
gives them hell.

So... They basically super-dry their air with a desiccant and dryers so
that it is down to 0.01% humidity or less and use absolutely no oil
whatsoever inside the unit.

After 2-3 years of running like this, the unit doesn't stroke so well. The
seals are dried out and the cylinder, although still sealed properly, needs
up to 80 PSI air to stroke at all. Normally, they stroke at 15 PSI or so...

Anyone know of a lubricant that could be used that would not cause medical
(food grade or better maybe?) issues?

Can't use oil, grease, dry powder stuff, etc. Can't even use water...

I was thinking something like medical grade alcohol or acetone that
disappears all by itself if it gets to the atmosphere... But I bet there is
a better option.

Thoughts?

As a side note, the tube and quill will stroke millions of times with no
lube without wearing out. We've done long-term tests... The tolerances
between quill and tube are around 0.001" and the quill diameter is around 3"
if it matters.

Having just read a bunch of posts about air tools and proper lube made me
think that there might be an expert in here with some ideas...

I suspect you need to simply change the seal material. Possibly
something like a teflon seal would do the job, not require lubricant or
dry out.

"Ignoramus32217" wrote in message
...
I see this as a win-win situation, an opportunity to sell them a new
cylinder every couple of years, and charge them $100 per hour
installing said cylinders.

Hear ye, hear ye, Merka at its finest!

But, donchaknow, who ultimately winds up footing the bill, and where does
sed bill get shoved?

Inyway, maybe a seal that itself wears/self-lubricates nicely, like mebbe
teflon, delrin, nylon, some composite?

Chemically speaking, anything with a lubricating viscosity is not likely to
evaporate quickly, and vice versa, and then you'd proly need fairly copious
amounts of it, as in a bath of sorts.

But, if contamination/biocompatibility is the Fed's real issue, mebbe a
joint-type synovial fluid would be acceptable? But the R&D, approval,
alladat would no doubt be prohibitive for you, unless the company is really
gung ho and will foot the bill.

My understanding is that AstroGlide and the new KY jellies are perty
bio-compatible, and if they work on the cylinder, mebbe you could skim some
off the top, and give the ole marriage a li'l boost, eh? Speaking of
cylinders'n'****....

But sheeit, iffin they charge any more for this g-d astroglide/KY jelly
****, I may just have to resort to foreplay..... goodgawd.....

--

Mr. PV'd

Mae West (yer fav CongressShill) to the Gangster (yer fav Lobbyist):
Hey, Big Boy, is that a wad (of cash) in yer pocket, or are you just
glad to see me??

Experiment on Homo Sapiens -- CEOs, Lawyers, and Politicians, in
particular.
Spare the animals.

Click here every day to feed an animal that needs you today.
www.theanimalrescuesite.com/



i

"Pete C." wrote in message
ster.com...

I suspect you need to simply change the seal material. Possibly
something like a teflon seal would do the job, not require lubricant or
dry out.

I can't "stretch" the teflon seal over my quill to get it to the seal
groove... I might be able tu cut it, but then they might complain about air
leakage.
--


Regards,
Joe Agro, Jr.
(800) 871-5022
01.908.542.0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com
Production Tapping: http://Production-Tapping-Equipment.com/
Flagship Site: http://www.Drill-N-Tap.com
VIDEOS: http://www.youtube.com/user/autodrill

V8013-R

"Ignoramus32217" wrote in message
...
I see this as a win-win situation, an opportunity to sell them a new
cylinder every couple of years, and charge them $100 per hour
installing said cylinders.

Yep. And they've got a bunch of 'em... But I feel guilty workign that way
if a simple answer might exist.

I told the guy (joking around) to use "slippery air" like Argon or Nitrogen
and he thought I was serious. I felt bad about that too.
--


Regards,
Joe Agro, Jr.
(800) 871-5022
01.908.542.0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com
Production Tapping: http://Production-Tapping-Equipment.com/
Flagship Site: http://www.Drill-N-Tap.com
VIDEOS: http://www.youtube.com/user/autodrill

V8013-R

On Wed, 15 Jul 2009 15:04:45 -0400, "Joe AutoDrill"
wrote:

"Pete C." wrote in message
nster.com...

I suspect you need to simply change the seal material. Possibly
something like a teflon seal would do the job, not require lubricant or
dry out.

I can't "stretch" the teflon seal over my quill to get it to the seal
groove... I might be able tu cut it, but then they might complain about air
leakage.

Have you looked into what kind of seals they use in the
oiless air compressors? I understood that it was some sort
of teflon seal. Maybe you could duplicate whatever they are
doing...

--
Leon Fisk
Grand Rapids MI/Zone 5b
Remove no.spam for email

On Wed, 15 Jul 2009 14:26:47 -0400, "Joe AutoDrill"
wrote:

I'm copying both the metalworking and woodworking groups. I hope this
doesn't **** anyone off too badly. I believe the answers and knowledge that
may get passed around is mutually beneficial. Thus the breach in newsgroup
etiquette.

Anyhow... I've got a unique problem.

I sell a product that acts basically like an air cylinder. It has a tube
(hard chrome plated inside for you metal guys) with a quill (hard chrome
plated also) and some rubber seals inside.

One of my customers is a medical giant. They can't have ANY type of
lubricant in the cylinder as they run the drill or the FDA comes in and
gives them hell.

So... They basically super-dry their air with a desiccant and dryers so
that it is down to 0.01% humidity or less and use absolutely no oil
whatsoever inside the unit.

After 2-3 years of running like this, the unit doesn't stroke so well. The
seals are dried out and the cylinder, although still sealed properly, needs
up to 80 PSI air to stroke at all. Normally, they stroke at 15 PSI or so...

Anyone know of a lubricant that could be used that would not cause medical
(food grade or better maybe?) issues?

Can't use oil, grease, dry powder stuff, etc. Can't even use water...

I was thinking something like medical grade alcohol or acetone that
disappears all by itself if it gets to the atmosphere... But I bet there is
a better option.

Thoughts?

As a side note, the tube and quill will stroke millions of times with no
lube without wearing out. We've done long-term tests... The tolerances
between quill and tube are around 0.001" and the quill diameter is around 3"
if it matters.

Having just read a bunch of posts about air tools and proper lube made me
think that there might be an expert in here with some ideas...

Regards,
Joe Agro, Jr.
(800) 871-5022
01.908.542.0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com
Production Tapping: http://Production-Tapping-Equipment.com/
Flagship Site: http://www.Drill-N-Tap.com
VIDEOS: http://www.youtube.com/user/autodrill

V8013-R




Is the MTBF on this unit significantly less than other elements of the
system that have a similar, or greater replacement cost?



Regards,

Tom Watson
http://home.comcast.net/~tjwatson1/

Some random thoughts: Since you can't stretch the seal to get it into the
groove, how about unscrewing the end of the piston to expose the groove?

I once toured a tea-bag factory, and they were using a special non-toxic
lubricant on the staple wire (holding the string to the bag.)

How about using a teflon liner in the cylinder?

How about making the piston out of teflon or nylon?

Is the MTBF on this unit significantly less than other elements of the
system that have a similar, or greater replacement cost?

Unknown.

Regards,
Joe Agro, Jr.
(800) 871-5022
01.908.542.0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com
Production Tapping: http://Production-Tapping-Equipment.com/
Flagship Site: http://www.Drill-N-Tap.com
VIDEOS: http://www.youtube.com/user/autodrill

V8013-R

On Jul 15, 3:26*pm, Leon Fisk wrote:
On Wed, 15 Jul 2009 15:04:45 -0400, "Joe AutoDrill"

wrote:
"Pete C." wrote in message
nster.com...

I suspect you need to simply change the seal material. Possibly
something like a teflon seal would do the job, not require lubricant or
dry out.

I can't "stretch" the teflon seal over my quill to get it to the seal
groove... *I might be able tu cut it, but then they might complain about air
leakage.

Have you looked into what kind of seals they use in the
oiless air compressors? I understood that it was some sort
of teflon seal. Maybe you could duplicate whatever they are
doing...

--
Leon Fisk
Grand Rapids *MI/Zone 5b
Remove no.spam for email

I just replaced the piston and sleeve on my oiless air compressor last
week. The seal is clamped between the head of the cylinder and held in
place by a screw. The teflon is just a ring that seals against the
sleeve and slides back and forth.

I was under the impression that teflon is carcinogenic if ingested,
which is why you should toss pots and pans with flaking teflon on
them.

-Nathan

"Leo Lichtman" wrote in message
...
Some random thoughts: Since you can't stretch the seal to get it into the
groove, how about unscrewing the end of the piston to expose the groove?

The quill is a solid piece of steel machined to spec. Nothing to
disassemble.

I once toured a tea-bag factory, and they were using a special non-toxic
lubricant on the staple wire (holding the string to the bag.)

Wonder if it was tea flavored? grin

How about using a teflon liner in the cylinder?

Tolerances are too close. Liner would have to be 0.0005" or less or the
quill would have to be resized and re-chrome plated, then reground...
Redesigning the machine is not an option. It would be like saying to change
the engine on a car to solve a fuel problem.

How about making the piston out of teflon or nylon?

Not nearly durable enough. Plus, it goes back to the redesigning the
machine thing.

If I can't find something to simply inject into the system that fixes the
problem, they will have to run dry.

Regards,
Joe Agro, Jr.
(800) 871-5022
01.908.542.0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com
Production Tapping: http://Production-Tapping-Equipment.com/
Flagship Site: http://www.Drill-N-Tap.com
VIDEOS: http://www.youtube.com/user/autodrill

V8013-R

On Wed, 15 Jul 2009 16:02:07 -0400, "Joe AutoDrill"
wrote:

Is the MTBF on this unit significantly less than other elements of the
system that have a similar, or greater replacement cost?

Unknown.

Regards,
Joe Agro, Jr.
(800) 871-5022
01.908.542.0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com
Production Tapping: http://Production-Tapping-Equipment.com/
Flagship Site: http://www.Drill-N-Tap.com
VIDEOS: http://www.youtube.com/user/autodrill

V8013-R




It would be interesting to know this.

"Failure" could be an applied metric that references PSI needed to
cycle, or a specific cycling rate. At a certain point either of these
could become critical to the proper functioning of the system.

If your unit has a MTBF that is in line with other elements of the
system, it would be reasonable to conclude that there is a MTBF for
the system as a whole and that the replacement of your unit would be
covered under general maintenance, making your product immune from
being singled out as the primary cause of system failure.



Regards,

Tom Watson
http://home.comcast.net/~tjwatson1/

On Jul 15, 2:26*pm, "Joe AutoDrill" wrote:
I'm copying both the metalworking and woodworking groups. *I hope this
doesn't **** anyone off too badly. *I believe the answers and knowledge that
may get passed around is mutually beneficial. *Thus the breach in newsgroup
etiquette.

You are breach-free in this instance. Cross-posting is preferable
when the topic pertains to two groups as it will eliminate most
duplication of answers.

Anyhow... *I've got a unique problem.

I sell a product that acts basically like an air cylinder. *It has a tube
(hard chrome plated inside for you metal guys) with a quill (hard chrome
plated also) and some rubber seals inside.

One of my customers is a medical giant. *They can't have ANY type of
lubricant in the cylinder as they run the drill or the FDA comes in and
gives them hell.

So... *They basically super-dry their air with a desiccant and dryers so
that it is down to 0.01% humidity or less and use absolutely no oil
whatsoever inside the unit.

After 2-3 years of running like this, the unit doesn't stroke so well. *The
seals are dried out and the cylinder, although still sealed properly, needs
up to 80 PSI air to stroke at all. *Normally, they stroke at 15 PSI or so...

Anyone know of a lubricant that could be used that would not cause medical
(food grade or better maybe?) issues?

Can't use oil, grease, dry powder stuff, etc. *Can't even use water...

I was thinking something like medical grade alcohol or acetone that
disappears all by itself if it gets to the atmosphere... *But I bet there is
a better option.

Thoughts?

As a side note, the tube and quill will stroke millions of times with no
lube without wearing out. *We've done long-term tests... *The tolerances
between quill and tube are around 0.001" and the quill diameter is around 3"
if it matters.

Having just read a bunch of posts about air tools and proper lube made me
think that there might be an expert in here with some ideas...

As others have said, Teflon comes to mind first. Perhaps you can warm
the Teflon to a more plastic state and slip it into place?

Wiki had this to say about PTFE:
"Due to its low friction, it is used for applications where sliding
action of parts is needed: bearings, bushings, gears, slide plates,
etc. In these applications it performs significantly better than nylon
and acetal; it is comparable to ultra high-molecular weight
polyethylene (UHMWPE), although UHMWPE is more resistant to wear than
Teflon. For these applications, versions of teflon with mineral oil or
molybdenum disulfide embedded as additional lubricants in its matrix
are being manufactured."

and this:
"Other polymers with similar composition are also known by the Teflon
name:
* PFA (perfluoroalkoxy polymer resin)
* FEP (fluorinated ethylene-propylene)
They retain the useful properties of PTFE of low friction and non-
reactivity, but are more easily formable. FEP is softer than PTFE and
melts at 260 °C; it is highly transparent and resistant to sunlight."

Your answer will probably be in there somewhere.

R

Is the MTBF on this unit significantly less than other elements of the
system that have a similar, or greater replacement cost?

Unknown.

It would be interesting to know this.

"Failure" could be an applied metric that references PSI needed to
cycle, or a specific cycling rate. At a certain point either of these
could become critical to the proper functioning of the system.

If your unit has a MTBF that is in line with other elements of the
system, it would be reasonable to conclude that there is a MTBF for
the system as a whole and that the replacement of your unit would be
covered under general maintenance, making your product immune from
being singled out as the primary cause of system failure.

Not a concern. They are happy with the unit and are even happy sending it
back to us for rebuilds regularly... But I always look for a bettr answer
for my customers. No need to shaft them if there is a simple answer out
there someplace. I sell enough untis that rebuilds don't make a difference
between cold cereal and steak for dinner.
--


Regards,
Joe Agro, Jr.
(800) 871-5022
01.908.542.0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com
Production Tapping: http://Production-Tapping-Equipment.com/
Flagship Site: http://www.Drill-N-Tap.com
VIDEOS: http://www.youtube.com/user/autodrill

V8013-R

In article , "Joe AutoDrill" wrote:
[...]
If I can't find something to simply inject into the system that fixes the
problem, they will have to run dry.

Surely the FDA has a list somewhere of approved lubricants?

Joe AutoDrill wrote:

"Pete C." wrote in message
ster.com...

I suspect you need to simply change the seal material. Possibly
something like a teflon seal would do the job, not require lubricant or
dry out.

I can't "stretch" the teflon seal over my quill to get it to the seal
groove... I might be able tu cut it, but then they might complain about air
leakage.

"Coiled" teflon backup washers are pretty standard items in pneumatic
and hydraulic components and they can be coiled into a groove. The air
pressure should push the coil together enough to minimize leakage.

Also take a look at the V-ring seals on McMaster.com, they look like you
could cut them and have minimal leakage as long as you stack them with
the cuts located opposite each other as you stack them.

Another possibility on McMaster.com is the "Spring loaded PTFE shaft
seals" which may have enough play to let you fit them.

On Wed, 15 Jul 2009 20:13:51 GMT, (Doug Miller)
wrote:

In article , "Joe AutoDrill" wrote:
[...]
If I can't find something to simply inject into the system that fixes the
problem, they will have to run dry.

Surely the FDA has a list somewhere of approved lubricants?



KY?



Regards,

Tom Watson
http://home.comcast.net/~tjwatson1/

Joe AutoDrill wrote:
....
I sell a product that acts basically like an air cylinder. It has a tube
(hard chrome plated inside for you metal guys) with a quill (hard chrome
plated also) and some rubber seals inside.

One of my customers is a medical giant. They can't have ANY type of
lubricant in the cylinder as they run the drill or the FDA comes in and
gives them hell.
....
Anyone know of a lubricant that could be used that would not cause medical
(food grade or better maybe?) issues?

Can't use oil, grease, dry powder stuff, etc. Can't even use water...

I was thinking something like medical grade alcohol or acetone that
disappears all by itself if it gets to the atmosphere... But I bet there is
a better option.

Thoughts?
....

Not on a direct solution, no...

Curiosity--is this in an actual medical device or used in the
manufacture of a device? Might have bearing on how to approach, I don't
know.

Only suggestions I would have would be (a) have you tried working w/ the
FDA "advice/guidance for approval" side instead of enforcement? Same
overall organization but different hats. Not my baliwick but coworker
did some consulting work in medical device area and actually did get
some useful feedback that way, and (b) any chance you could find
somebody in local/state university w/ the med school/med-engineering
school in the field that might talk to you?

--

nhurst wrote:

I was under the impression that teflon is carcinogenic if ingested,
which is why you should toss pots and pans with flaking teflon on
them.

Don't think so, they use it for surgical purposes. I believe the
problem with flaking teflon on pots is that it exposes you to bare
aluminum underneath which has been associated (though not definitively)
with Alzheimer's. That said, plenty of restaurants cook on bare aluminum.

Chris

Chris Friesen wrote:

nhurst wrote:

I was under the impression that teflon is carcinogenic if ingested,
which is why you should toss pots and pans with flaking teflon on
them.

Don't think so, they use it for surgical purposes. I believe the
problem with flaking teflon on pots is that it exposes you to bare
aluminum underneath which has been associated (though not definitively)
with Alzheimer's.

The flaws in the one poor study that claimed any association between AL
and Alz have been thoroughly identified and the claimed association
disproven by many better controlled studies.

The only issue with teflon that has any shred of truth is toxicity of
vapors released from seriously overheated teflon (500 degrees F) to
birds.

That said, plenty of restaurants cook on bare aluminum.

Nearly all restaurants cook in basic AL cookware.

On Jul 15, 4:20*pm, Chris Friesen wrote:
nhurst wrote:
I was under the impression that teflon is carcinogenic if ingested,
which is why you should toss pots and pans with flaking teflon on
them.

Don't think so, they use it for surgical purposes. *I believe the
problem with flaking teflon on pots is that it exposes you to bare
aluminum underneath which has been associated (though not definitively)
with Alzheimer's. *That said, plenty of restaurants cook on bare aluminum.

Teflon breaks down above 500 degrees, and I'm sure that some of the
polymer is already loosening it's bonds before that. Pretty much all
monomers are carcinogenic. Then again, so is sunlight, and probably
jogging.

R

"Joe AutoDrill" wrote in message
...
I'm copying both the metalworking and woodworking groups. I hope this
doesn't **** anyone off too badly. I believe the answers and knowledge
that may get passed around is mutually beneficial. Thus the breach in
newsgroup etiquette.

Anyhow... I've got a unique problem.

I sell a product that acts basically like an air cylinder. It has a tube
(hard chrome plated inside for you metal guys) with a quill (hard chrome
plated also) and some rubber seals inside.

One of my customers is a medical giant. They can't have ANY type of
lubricant in the cylinder as they run the drill or the FDA comes in and
gives them hell.

So... They basically super-dry their air with a desiccant and dryers so
that it is down to 0.01% humidity or less and use absolutely no oil
whatsoever inside the unit.

After 2-3 years of running like this, the unit doesn't stroke so well.
The seals are dried out and the cylinder, although still sealed properly,
needs up to 80 PSI air to stroke at all. Normally, they stroke at 15 PSI
or so...

Anyone know of a lubricant that could be used that would not cause medical
(food grade or better maybe?) issues?

Can't use oil, grease, dry powder stuff, etc. Can't even use water...

I was thinking something like medical grade alcohol or acetone that
disappears all by itself if it gets to the atmosphere... But I bet there
is a better option.

Thoughts?

As a side note, the tube and quill will stroke millions of times with no
lube without wearing out. We've done long-term tests... The tolerances
between quill and tube are around 0.001" and the quill diameter is around
3" if it matters.

Having just read a bunch of posts about air tools and proper lube made me
think that there might be an expert in here with some ideas...

Regards,
Joe Agro, Jr.
(800) 871-5022
01.908.542.0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com
Production Tapping: http://Production-Tapping-Equipment.com/
Flagship Site: http://www.Drill-N-Tap.com
VIDEOS: http://www.youtube.com/user/autodrill

V8013-R

The FDA allows food grade silicone in the main valve of Rainsoft water
softeners. I've been using it for about 15 years.

Max

If I can't find something to simply inject into the system that fixes the
problem, they will have to run dry.

Surely the FDA has a list somewhere of approved lubricants?

They sure do. However, given the nature of what they are doing, they need
to go to the FDA for approval every time they change something in the system
such as this... and their reluctance to do that is clear. If the machine
changes slightly, apparently the loophole exists that they don't need a new
approval.

I wish I knew the exact application... But for all I know, they're using
them on live patients knee cap replacement parts - in body already... I
simply don't know...

Regards,
Joe Agro, Jr.
(800) 871-5022
01.908.542.0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com
Production Tapping: http://Production-Tapping-Equipment.com/
Flagship Site: http://www.Drill-N-Tap.com
VIDEOS: http://www.youtube.com/user/autodrill

V8013-R

"Pete C." wrote in message
ster.com...

"Coiled" teflon backup washers are pretty standard items in pneumatic
and hydraulic components and they can be coiled into a groove. The air
pressure should push the coil together enough to minimize leakage.

Also take a look at the V-ring seals on McMaster.com, they look like you
could cut them and have minimal leakage as long as you stack them with
the cuts located opposite each other as you stack them.

Another possibility on McMaster.com is the "Spring loaded PTFE shaft
seals" which may have enough play to let you fit them.

Who is this McMaster fellow? grin

I'll check it out shortly. Seem like good options. Thank you.
--


Regards,
Joe Agro, Jr.
(800) 871-5022
01.908.542.0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com
Production Tapping: http://Production-Tapping-Equipment.com/
Flagship Site: http://www.Drill-N-Tap.com
VIDEOS: http://www.youtube.com/user/autodrill

V8013-R

On Wed, 15 Jul 2009 16:10:48 -0400, "Joe AutoDrill"
wrote:

Is the MTBF on this unit significantly less than other elements of the
system that have a similar, or greater replacement cost?

Unknown.

It would be interesting to know this.

"Failure" could be an applied metric that references PSI needed to
cycle, or a specific cycling rate. At a certain point either of these
could become critical to the proper functioning of the system.

If your unit has a MTBF that is in line with other elements of the
system, it would be reasonable to conclude that there is a MTBF for
the system as a whole and that the replacement of your unit would be
covered under general maintenance, making your product immune from
being singled out as the primary cause of system failure.

Not a concern. They are happy with the unit and are even happy sending it
back to us for rebuilds regularly... But I always look for a bettr answer
for my customers. No need to shaft them if there is a simple answer out
there someplace. I sell enough untis that rebuilds don't make a difference
between cold cereal and steak for dinner.



I think that you have an honorable intent, Joe, and I won't belabor my
point beyond this post.

However, if the system has a MTBF and, if your unit is overly
engineered, or overly manufactured, making it the most costly part,
that might outlive the MTBF by many times - I don't think that you are
doing anyone a favor.

There are mission critical systems and mission critical components of
those systems.

If your component is going to get tossed at a thousand hours, and you
made it to last ten thousand hours, at a cost of fifty percent more
than one that would last a thousand hours - I don't think that you are
shafting the customer by staying with a unit that lasts a thousand
hours.


As always,



YMMV




Regards,

Tom Watson
http://home.comcast.net/~tjwatson1/

Joe AutoDrill wrote:
I'm copying both the metalworking and woodworking groups. I hope this
doesn't **** anyone off too badly. I believe the answers and knowledge that
may get passed around is mutually beneficial. Thus the breach in newsgroup
etiquette.

Anyhow... I've got a unique problem.

I sell a product that acts basically like an air cylinder. It has a tube
(hard chrome plated inside for you metal guys) with a quill (hard chrome
plated also) and some rubber seals inside.

One of my customers is a medical giant. They can't have ANY type of
lubricant in the cylinder as they run the drill or the FDA comes in and
gives them hell.

So... They basically super-dry their air with a desiccant and dryers so
that it is down to 0.01% humidity or less and use absolutely no oil
whatsoever inside the unit.

After 2-3 years of running like this, the unit doesn't stroke so well. The
seals are dried out and the cylinder, although still sealed properly, needs
up to 80 PSI air to stroke at all. Normally, they stroke at 15 PSI or so...

Anyone know of a lubricant that could be used that would not cause medical
(food grade or better maybe?) issues?

I would try teflon rings for the seals.
It sounds like this is something that is used under true sterile
controls. I would assume it can be disassembled for autoclaving?



Can't use oil, grease, dry powder stuff, etc. Can't even use water...

I was thinking something like medical grade alcohol or acetone that
disappears all by itself if it gets to the atmosphere... But I bet there is
a better option.

Thoughts?

As a side note, the tube and quill will stroke millions of times with no
lube without wearing out. We've done long-term tests... The tolerances
between quill and tube are around 0.001" and the quill diameter is around 3"
if it matters.

Having just read a bunch of posts about air tools and proper lube made me
think that there might be an expert in here with some ideas...

Regards,
Joe Agro, Jr.
(800) 871-5022
01.908.542.0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com
Production Tapping: http://Production-Tapping-Equipment.com/
Flagship Site: http://www.Drill-N-Tap.com
VIDEOS: http://www.youtube.com/user/autodrill

V8013-R





--
Steve W.

dpb wrote:
Joe AutoDrill wrote:
...
I sell a product that acts basically like an air cylinder. It has a
tube (hard chrome plated inside for you metal guys) with a quill (hard
chrome plated also) and some rubber seals inside.

One of my customers is a medical giant. They can't have ANY type of
lubricant in the cylinder as they run the drill or the FDA comes in
and gives them hell.
...
Anyone know of a lubricant that could be used that would not cause
medical (food grade or better maybe?) issues?

Can't use oil, grease, dry powder stuff, etc. Can't even use water...

I was thinking something like medical grade alcohol or acetone that
disappears all by itself if it gets to the atmosphere... But I bet
there is a better option.

Thoughts?
...

Not on a direct solution, no...

Curiosity--is this in an actual medical device or used in the
manufacture of a device? Might have bearing on how to approach, I don't
know.

Only suggestions I would have would be (a) have you tried working w/ the
FDA "advice/guidance for approval" side instead of enforcement? Same
overall organization but different hats. Not my baliwick but coworker
did some consulting work in medical device area and actually did get
some useful feedback that way, and (b) any chance you could find
somebody in local/state university w/ the med school/med-engineering
school in the field that might talk to you?

http://www.canica.com/index.asp

A medical tool company, operated by Rob Lee's father IIRC (of Lee Valley
Tool Fame).

I don't see anything directly related to your issue, but they do have
engineers and such that are familiar with surgical/medical equipment.

--
Froz...

"Joe AutoDrill" wrote in message
...
Is the MTBF on this unit significantly less than other elements of the
system that have a similar, or greater replacement cost?

Unknown.

Regards,
Joe Agro, Jr.
(800) 871-5022
01.908.542.0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com
Production Tapping: http://Production-Tapping-Equipment.com/
Flagship Site: http://www.Drill-N-Tap.com
VIDEOS: http://www.youtube.com/user/autodrill

V8013-R

Joe: I don't have a solution for you but I would like to say I like your
attitude regarding improving your product without the user bitching. A rare
attitude in today's business world. If I ever find myself in need of your
type of products I will jump your direction.

Stu Fields

I would try teflon rings for the seals.
It sounds like this is something that is used under true sterile
controls. I would assume it can be disassembled for autoclaving?

I doubt they cook it... In fact, I can pretty much guarantee they don't...
--


Regards,
Joe Agro, Jr.
(800) 871-5022
01.908.542.0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com
Production Tapping: http://Production-Tapping-Equipment.com/
Flagship Site: http://www.Drill-N-Tap.com
VIDEOS: http://www.youtube.com/user/autodrill

V8013-R

"FrozenNorth" wrote in message
...

http://www.canica.com/index.asp

A medical tool company, operated by Rob Lee's father IIRC (of Lee Valley
Tool Fame).

I don't see anything directly related to your issue, but they do have
engineers and such that are familiar with surgical/medical equipment.

Another lead I'll check out. Thank you.
--


Regards,
Joe Agro, Jr.
(800) 871-5022
01.908.542.0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com
Production Tapping: http://Production-Tapping-Equipment.com/
Flagship Site: http://www.Drill-N-Tap.com
VIDEOS: http://www.youtube.com/user/autodrill

V8013-R

On Jul 15, 2:04*pm, nhurst wrote:
On Jul 15, 3:26*pm, Leon Fisk wrote:





On Wed, 15 Jul 2009 15:04:45 -0400, "Joe AutoDrill"

wrote:
"Pete C." wrote in message
nster.com...

I suspect you need to simply change the seal material. Possibly
something like a teflon seal would do the job, not require lubricant or
dry out.

I can't "stretch" the teflon seal over my quill to get it to the seal
groove... *I might be able tu cut it, but then they might complain about air
leakage.

Have you looked into what kind of seals they use in the
oiless air compressors? I understood that it was some sort
of teflon seal. Maybe you could duplicate whatever they are
doing...

--
Leon Fisk
Grand Rapids *MI/Zone 5b
Remove no.spam for email

I just replaced the piston and sleeve on my oiless air compressor last
week. The seal is clamped between the head of the cylinder and held in
place by a screw. The teflon is just a ring that seals against the
sleeve and slides back and forth.

I was under the impression that teflon is carcinogenic if ingested,
which is why you should toss pots and pans with flaking teflon on
them.

-Nathan- Hide quoted text -

- Show quoted text -

Can't let that one by. Teflon is basically inert, including
biologically, at room tempertures and you have to heat it quite a bit
to get it to decompose. To glue it, the teflon surface has to be
chemically treated to turn it into something not-teflon so the glue
will stick. I've not heard about having to toss non-stick cookware
that's had the surface damaged, probably happens anyway because it's a
pain to use that way. The carcinogenic part is the chemicals used to
make and attach the coating, not the coating itself. Just had a green
spasm in the press about that in the last few months. A lot of
current cookware is now silicone coated, just waiting for somebody to
find a problem with THAT.

Stan

"Stu Fields" wrote in message
...

Joe: I don't have a solution for you but I would like to say I like your
attitude regarding improving your product without the user bitching. A
rare attitude in today's business world. If I ever find myself in need of
your type of products I will jump your direction.

Thanks Stu. The way I see it, it's the only proper way to do business
anyhow. I appreciate the compliment.

Regards,
Joe Agro, Jr.
(800) 871-5022
01.908.542.0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com
Production Tapping: http://Production-Tapping-Equipment.com/
Flagship Site: http://www.Drill-N-Tap.com
VIDEOS: http://www.youtube.com/user/autodrill

V8013-R

Joe AutoDrill wrote:
If I can't find something to simply inject into the system that fixes the
problem, they will have to run dry.
Surely the FDA has a list somewhere of approved lubricants?

They sure do. However, given the nature of what they are doing, they need
to go to the FDA for approval every time they change something in the system
such as this... and their reluctance to do that is clear. If the machine
changes slightly, apparently the loophole exists that they don't need a new
approval.

I wish I knew the exact application... But for all I know, they're using
them on live patients knee cap replacement parts - in body already... I
simply don't know...
....
So iow the user has implied they're not going to rock the boat but if
the manufacturer changes the equipment, "well, how were _we_ to know???"?

Seems like an uncomfortable position to be in. Do you certify the
equipment to any Standard or spec if you do simply change a seal
material that would be in contravention to?

Seems hard to evaluate what, if any, effect a fix might have if you
don't even know what it is your device application is...

I'd assumed you were working w/ the end user on this rather than in
isolation.

--

Joe AutoDrill wrote:
Is the MTBF on this unit significantly less than other elements of
the system that have a similar, or greater replacement cost?

Unknown.

You didn't say what you're using for a seal now. There are a zillion
materials out there--kind of hard to make a suggestion until one knows what
it has to beat.

"Joe AutoDrill" wrote:

Anyhow... I've got a unique problem.

I sell a product that acts basically like an air cylinder. It has a
tube (hard chrome plated inside for you metal guys) with a quill
(hard chrome plated also) and some rubber seals inside.

One of my customers is a medical giant. They can't have ANY type of
lubricant in the cylinder as they run the drill or the FDA comes in
and gives them hell.

So... They basically super-dry their air with a desiccant and
dryers so that it is down to 0.01% humidity or less and use
absolutely no oil whatsoever inside the unit.

After 2-3 years of running like this, the unit doesn't stroke so
well. The seals are dried out and the cylinder, although still
sealed properly, needs up to 80 PSI air to stroke at all. Normally,
they stroke at 15 PSI or so...

Anyone know of a lubricant that could be used that would not cause
medical (food grade or better maybe?) issues?

Can't use oil, grease, dry powder stuff, etc. Can't even use
water...

I was thinking something like medical grade alcohol or acetone that
disappears all by itself if it gets to the atmosphere... But I bet
there is a better option.

Anybody looked at dry film lubricants?

Lew

On Wed, 15 Jul 2009 14:26:47 -0400, "Joe AutoDrill"
wrote:

Leaping in several hours too late, but...

PTFE piston rings or even cast iron piston rings. Cast iron may well be
better.

If perfect sealing is vital, look up Clupet style piston rings. If perfect
sealing is not a major problem, just use a split ring with a few thou of
clearance.

Mark Rand
RTFM

On Wed, 15 Jul 2009 15:21:25 -0400, Joe AutoDrill wrote:

"Ignoramus32217" wrote in message
...
I see this as a win-win situation, an opportunity to sell them a new
cylinder every couple of years, and charge them $100 per hour
installing said cylinders.

Yep. And they've got a bunch of 'em... But I feel guilty workign that
way if a simple answer might exist.

Besides, someone will come along and say that _their_ stuff doesn't have
the problem and they'll boot you out. Several years later, when they
find out that that company's rep was wrong or lying it'll be too late.

I told the guy (joking around) to use "slippery air" like Argon or
Nitrogen and he thought I was serious. I felt bad about that too.

You B*****.

--
www.wescottdesign.com

On Wed, 15 Jul 2009 15:04:45 -0400, Joe AutoDrill wrote:

"Pete C." wrote in message
ster.com...

I suspect you need to simply change the seal material. Possibly
something like a teflon seal would do the job, not require lubricant or
dry out.

I can't "stretch" the teflon seal over my quill to get it to the seal
groove... I might be able tu cut it, but then they might complain about
air leakage.

Can you heat it up? (I suspect not -- I can't recall teflon getting
significantly more pliable with heat).

Are there alternatives to what you have that are pliable and slippery?
(I can't think of any, at least none that won't be impregnated with
something nasty, but I thought I'd toss out the notion).

Can you make a long split ring with a feature on the inside to engage the
o-ring groove on the quill, and a serpentine cut that gets squeezed
closed when you put the rig into the piston?

You may be able to make a ring with a feature that's big enough to snap
into the o-ring groove and stay, but shallow enough (and maybe tapered)
enough that the ring will expand over the quill -- like this, with all
due allowances for ASCII art:


..-----------------------------------.
'-----------. .--------------'
'--------'





.--------.
..-----------' '--------------.
'-----------------------------------'

If your quill is chamfered enough on the end you may even be able to
retain sharp edges on both sides of the ridge.
--
www.wescottdesign.com

"Pete C." writes:

That said, plenty of restaurants cook on bare aluminum.

Nearly all restaurants cook in basic AL cookware.

I was under the impression that there was a thin layer of
stainless steel over the AL core (to avoid staining, e.g. tomato sauce).

scott