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Chris D
09-01-2005, 05:15 PM
Hi group

I need to make a thrustbearing of sorts. This bearing will not have alot of load - probably measured in ounces of load rather than pounds. This thrust bearing will be pushing against a brass shaft with a shoulder. The application does not lend itself well to lubricants so I am thinking along the lines of a plastic that is self lubricating.

The major problem I see is the speed at which this shaft is rotating, around 2000 RPM and at approx 1.75" diameter, the surface speed is somewhere around 1000 SFM - pretty darn high.

Anyone have any suggestions as to what material I could use for this? If needed, I could use a grease of some sort but not oil.

TIA

Chris

ViperTX
09-01-2005, 10:52 PM
Delrin.

svenakela
09-02-2005, 03:21 AM
http://www.igus.com

gripper
09-02-2005, 02:15 PM
Hi ,I think ther's a plastic called "Oilatron" which is a nylon it might help you but it's a pain to machine.

murphy625
09-02-2005, 02:57 PM
There is a material called UHMW.. (Ultra High Molecular Weight) plastic. UHMW on UHMW has the same friction coefficient as Ice on Ice.

Its fairly inexpensive also... There is another new one called VUHMW or something like that.. From what I understand, this is the "food grade" or one step even better than the original UHMW.. (im not sure about the "V" prefix )

I bought mine from a place called Garland Plastics.

Geof
09-02-2005, 04:35 PM
You say the shaft is brass but do not identify the material of the housing for the thrust washer. If the housing is also a good conductor of heat make a thin thrust washer using UHMW or Teflon with a backup washer in brass. The shaft, backup washer and housing will act as a heatsink keeping the thrust washer from getting too hot.

Chris D
09-03-2005, 07:43 AM
Thanks guys,

Lots of good information there for me to research. From what it looks like though from what I have found is that "plastic" bearings max out at around 200~300 sfm. But the search and research goes on.

Thanks again!

Chris