Hello Barry, that is a really great looking hinge setup in your picture. =
 How did it work and what held the wires into the other hinge pieces.  =
Was it on a Lehman seismometer?  Sure looks interesting.
Jim Allen

From: Barry Lotz=20
Sent: Thursday, April 05, 2012 6:00 PM
To: psnlist@.................
Subject: Re: SPREGNETHER HORIZONAL SEISMOMETER

James
Years ago I tried to build one using an isometric drawing and STM's =
electronics. It worked well but not consistantly. I build the hinge =
using a music wire in a dumb bell fashion. I have to look at in storage =
to see how I made it. Here is a photo I took "back when". The sensor =
mass was not to large so the tension on the wire may not be as high as =
yours.  http://www.seismicvault.com/sitebuilder/images/HINGE_12H.jpg
I'll find out what I did and get back to you.


Regards
Barry
www.seismicvault.com





-------------------------------------------------------------------------=
-------
From: JAMES C ALLEN 
To: psnlist@..............
Sent: Thu, April 5, 2012 9:08:03 AM
Subject: Re: SPREGNETHER HORIZONAL SEISMOMETER


Thanks Bob, Randy and Robert regarding ideas/ suggestions regarding =
making the Spregnether hinge.  I will explore some of the options =
suggested to try and have the brass drilled by one of the type of shops =
referenced that have the skill and equipment.
Again, thanks for your ideas
James Allen=20

From: Robert Thomasson=20
Sent: Thursday, April 05, 2012 4:43 AM
To: psnlist@.................
Subject: Re: SPREGNETHER HORIZONAL SEISMOMETER

James, not sure how you're trying to do the drilling, for holes that =
small you need a small precision drill press with an accurate chuck.  It =
would probably take more skill than I have to do it with a hand held =
drill.  My first thoughts are to try and find a real jeweler or =
silversmith or gunsmith, they may have the equipment to drill similar =
holes.  Or possibly an electronics assembly shop that does printed =
circuit board work.  It wouldn't hurt to call machine shops and ask, but =
most of them around here are more geared toward drilling 12" diameter =
holes.

Dremel sells a small drill press accessory for their variable speed Moto =
Tools that might work.  I think you'd need to use a slow speed.  You'd =
still need to devise an accurate method of holding the brass pieces =
while drilling and if it doesn't work and you don't have other uses for =
the drill press you're out $100+. =20

Bob



On Wed, Apr 4, 2012 at 9:45 PM, JAMES C ALLEN  =
wrote:

  I know that this is a long shot, but does anyone have parts for an old =
Spregnether horizontal seismometer?  Specifically the lower wire hinge.  =
The piece is a short wire with a round brass fitting at each end.  I =
tried to make it myself using piano wire and round brass stock.  But =
drilling the round brass stock to insert the wire into has been fraught =
with failure thus far since the very small drill bits I purchased at the =
hobby shop keep breaking,  Also, any advice on drilling an approximately =
..030 diameter hole in round brass stock would also be appreciated.  Do =
machine shops do this kind of work?
  James Allen







Hello Barry, that is a really great looking hinge setup in your=20
picture.  How did it work and what held the wires into the other =
hinge=20
pieces.  Was it on a Lehman seismometer?  Sure looks=20
interesting.
Jim Allen


 

From: Barry Lotz 
Sent: Thursday, April 05, 2012 6:00 PM
To: psnlist@.............. 
Subject: Re: SPREGNETHER HORIZONAL =
SEISMOMETER
 

James
Years=20
ago I tried to build one using an isometric drawing and STM's =
electronics. It=20
worked well but not consistantly. I build the hinge using a music wire =
in a dumb=20
bell fashion. I have to look at in storage to see how I made it. Here is =
a photo=20
I took "back when". The sensor mass was not to large so the tension on =
the wire=20
may not be as high as yours.  http://www.seismicvault.com/sitebuilder/images/HINGE_12H.=
jpg
I'll=20
find out what I did and get back to you.

 
Regards
Barry
www.seismicvault.com


 

 


From: JAMES C ALLEN=20
<jcallen1@...........>
To: =
psnlist@..............
Sent: Thu, April 5, 2012 9:08:03=20
AM
Subject: Re: =
SPREGNETHER=20
HORIZONAL SEISMOMETER




Thanks Bob, Randy and Robert regarding ideas/ suggestions regarding =
making=20
the Spregnether hinge.  I will explore some of the options =
suggested to try=20
and have the brass drilled by one of the type of shops referenced that =
have the=20
skill and equipment.
Again, thanks for your ideas
James Allen 


 

From: Robert Thomasson 
Sent: Thursday, April 05, 2012 4:43 AM
To: psnlist@.............. =

Subject: Re: SPREGNETHER HORIZONAL =
SEISMOMETER
 
James,=20
not sure how you're trying to do the drilling, for holes that small you =
need a=20
small precision drill press with an accurate chuck.  It would =
probably take=20
more skill than I have to do it with a hand held drill.  My first =
thoughts=20
are to try and find a real jeweler or silversmith or gunsmith, they may =
have the=20
equipment to drill similar holes.  Or possibly an electronics =
assembly shop=20
that does printed circuit board work.  It wouldn't hurt to call =
machine=20
shops and ask, but most of them around here are more geared toward =
drilling 12"=20
diameter holes.

Dremel sells a small drill press accessory for =
their=20
variable speed Moto Tools that might work.  I think you'd need to =
use a=20
slow speed.  You'd still need to devise an accurate method of =
holding the=20
brass pieces while drilling and if it doesn't work and you don't have =
other uses=20
for the drill press you're out $100+.  

Bob



On Wed, Apr 4, 2012 at 9:45 PM, JAMES C ALLEN =
<jcallen1@...........>=20
wrote:


  

  

  

  
I know that this is a long shot, but does anyone have parts for =
an old=20
  Spregnether horizontal seismometer?  Specifically the lower wire=20
  hinge.  The piece is a short wire with a round brass fitting at =
each=20
  end.  I tried to make it myself using piano wire and round brass=20
  stock.  But drilling the round brass stock to insert the wire =
into has=20
  been fraught with failure thus far since the very small drill bits I =
purchased=20
  at the hobby shop keep breaking,  Also, any advice on drilling an =

  approximately .030 diameter hole in round brass stock would also be=20
  appreciated.  Do machine shops do this kind of work?

  
James Allen