Meredith,

Here is another reference for ceramic ball bearings.
http://www.parktool.com/repair/readcalvinscorner.asp?id=170  The VXB
bearings are grade 5, that is much more round than the Small Parts bearings.


Gary

 

From: psn-l-request@.............. [mailto:psn-l-request@............... On
Behalf Of meredith lamb
Sent: Saturday, June 07, 2008 10:04 AM
To: psn-l@..............
Subject: Pivot balls; carbide and corundum reminder

 

Hi all,

Small Parts Inc. stocks carbide, synthetic ruby (red) and sapphire (clear)
balls that could probably
replace (and very likely enhance the pivot) of your steel ball bearings in
your seismometer pivots.  

The corundum sizes range from 1/64" up to 1/8" @ $3.45 up to $4.00 each.
You can buy in
quanity somewhat cheaper.  The sphericity (roundness) listed is 0.000025".

http://www.smallparts.com/products/descriptions/brb.cfm
http://www.smallparts.com/products/descriptions/BSP.cfm

The tungsten carbide balls range from 1/16" up to 1/2" @ $3.25 up to $16.80
each.  They
have metric sizes also.  The sphericity listed is 0.0006"...quite abit less
round than the corundum.

http://www.smallparts.com/products/descriptions/btc.CFM

The "big bite" of it all is their shipping/handling costs ~ $14.00 (USA)
irregardless of the small weight.
Their FedEx "2 day" shipping could be up to 4-5 days.  Ground shipping ~ 7
to 10 or more days.

Take care, Meredith
 

















Meredith,

Here is another reference for ceramic ball bearings. ht=
tp://www.parktool.com/repair/readcalvinscorner.asp?id=3D170 
The VXB bearings are grade 5, that is much more round than the Small =
Parts
bearings. 

Gary

 



From:=

psn-l-request@.............. [mailto:psn-l-request@............... On =
Behalf
Of meredith lamb

Sent: Saturday, June 07, 2008 10:04 AM

To: psn-l@..............

Subject: Pivot balls; carbide and corundum =
reminder



 

Hi all,



Small Parts Inc. stocks carbide, synthetic ruby (red) and sapphire =
(clear)
balls that could probably

replace (and very likely enhance the pivot) of your steel ball bearings =
in your
seismometer pivots.  



The corundum sizes range from 1/64" up to 1/8" @ $3.45 up to =
$4.00
each.  You can buy in

quanity somewhat cheaper.  The sphericity (roundness) listed is
0.000025".



http://www.smallparts.com/products/descriptions/brb.cfm=


http://www.smallparts.com/products/descriptions/BSP.cfm=




The tungsten carbide balls range from 1/16" up to 1/2" @ $3.25 =
up to
$16.80 each.  They

have metric sizes also.  The sphericity listed is =
0.0006"...quite
abit less round than the corundum.



http://www.smallparts.com/products/descriptions/btc.CFM=




The "big bite" of it all is their shipping/handling costs ~ =
$14.00
(USA) irregardless of the small weight.

Their FedEx "2 day" shipping could be up to 4-5 days.  =
Ground
shipping ~ 7 to 10 or more days.



Take care, Meredith