It might make a good crossed wire roll pivot - if it has about three 
brothers.  Crossed wire/band pivots are similar to a Rollamite except 
with space between the rolls so they're not running in contact. In 
previous Brett Nordgren tests these types of pivots had the lowest 
friction.

Brett, Chris Chapman and I are putting the finishing touches on a web 
site page with exact formulas in spreadsheet form for several pivots so 
amateurs can experiment with more insight into what is happening with a 
given geometry, i.e., finding the locus for the pivot along with some 
practical comments about their use.

Formulas/spreadsheets for:
+ Crossed wire/band rolls (such as separated Rollamite cylinders)
+ Crossed wire/band suspensions (such as used in LIGO vibration 
isolation systems)
+ ball on plate (the typical pivot of choice for many Lehmans) (a bit of 
advance warning -- this is one of the worst)
+ plate on ball (much better than ball on plate, and same complexity of 
construction.)

Regards,
Charles Patton





meredith lamb wrote:
> 
> Just for fun, I put this up on a web page.  What it is in normal use is 
> apparent, but the real scavenger
> in you question is; what do you think it could be used for in a 
> seismometer?  Yes; its a bit "outside the box"
> of what a great majority of home seismometer builders have done/tried/or 
> actually use.  I doubt the mystery
> description/use will take very long for someone to give the right answer.
>  
> http://seismometer.googlepages.com/mysteryseismometerpart
>  
> Take care, Meredith
>  
>    
> 
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