Hi All,

       Go to http://www.mcmaster.com/ and type in 'socket cap'. Scroll down 
and click on Swivel-end Socket Cap Screws. These look great for a seismometer 
mounting! They have some in stainless as well.

       Remember that to keep an accurate position during large temperature 
changes, the nut material needs to match the screw material. If you are using an 
Al baseplate, I suggest that you drill a clearance hole and stick the nut on 
the bottom face, either with epoxy or preferably two component acrylic 
adhesive. You can also buy nuts with an end extension which is press fitted into a 
hole in the baseplate, type in 'Nuts' and click on 'Captive Nuts'. 
Alternatively, you can use a face cutter to make a flat bottomed hole and press in an 
ordinary nut.

       The threads can be kept in tension using a second nut on top of the 
plate and a wavy washer. Type in 'wavy washer' and select '18-8 Stainless Steel 
Wave Washer'. If one washer does not give enough 'spring', you can build a 
stack of alternate wavy and plain washers.

       Another alternative is to use whatever thread you fancy, but screw an 
'Acorn Nut' onto the end of the bolt. These have a circular domed end and make 
quite good mountings.

       You can also get set screws with oval, circular, crown, round rotating 
and flat rotating ends...... 

       Regards,

       Chris Chapman
Hi All,



       Go to http://www.mcmaster.com/ and=20=
type in 'socket cap'. Scroll down and click on Swivel-end Socket Cap Screws.=
 These look great for a seismometer mounting! They have some in stainless as=
 well.



       Remember that to keep an accurate p=
osition during large temperature changes, the nut material needs to match th=
e screw material. If you are using an Al baseplate, I suggest that you drill=
 a clearance hole and stick the nut on the bottom face, either with epoxy or=
 preferably two component acrylic adhesive. You can also buy nuts with an en=
d extension which is press fitted into a hole in the baseplate, type in 'Nut=
s' and click on 'Captive Nuts'. Alternatively, you can use a face cutter to=20=
make a flat bottomed hole and press in an ordinary nut.



       The threads can be kept in tension=20=
using a second nut on top of the plate and a wavy washer. Type in 'wavy wash=
er' and select '18-8 Stainless Steel Wave Washer'. If one washer does not gi=
ve enough 'spring', you can build a stack of alternate wavy and plain washer=
s.



       Another alternative is to use whate=
ver thread you fancy, but screw an 'Acorn Nut' onto the end of the bolt. The=
se have a circular domed end and make quite good mountings.



       You can also get set screws with ov=
al, circular, crown, round rotating and flat rotating ends......=20



       Regards,



       Chris Chapman