Roll your own from fine pitch metric screws

http://www.minibearings.com.au/cgi-bin/datafill.pl?product=Screws%20-%20Machine%20-%20Steel&firstitem=1=post
pkg.s of 10  M1 x0.25 (1mm) 101.5 TPI screws for $1.31 Australian..

http://www.minibearings.com.au/cgi-bin/datafill.pl?product=Nuts%20-%20Hexagonal%20-%20Stainless%20Steel&firstitem=1=post
pkgs.s of 10  M1 x0.25 (1mm) 101.5 TPI nuts for $10.84 Australian  
(about $8.25 US) or so.

So total cost $10 plus shipping or about a $1 an adjustment point.  Find 
a couple of Bellville washers and use two nuts per screw to make 
anti-backlash versions, although once the weight of the seismometer is 
on the screw, it should be pretty much anti-backlash as is. 

Regards,
Charles Patton

( I started a Google search with
"80 tpi" screws
and found this in the first page of 10  of 428 returns.  So there are 
bound to be more.)


>

__________________________________________________________

Public Seismic Network Mailing List (PSN-L)