Hi Meredith,

The spring is 17-7  stainless condition C heat treated to condition =
CH900. Thickness is 12 mils.  The pivots are 2 mil stainless single axis =
..  Pivot length is only about 12 mils. They are held  tension by the C =
spring. A two axis pivot is not necessary.


Dave=20


  ----- Original Message -----=20
  From: meredith lamb=20
  To: psn-l@.................
  Sent: Friday, August 14, 2009 17:51
  Subject: Re: Real time traces


  Hi Brett and Dave,

  I'am "assuming" the "2" instruments is really the one ~ same ~ =
vertical (?), with either mechanical changes and/or
  feedback changes?

  As usual (for me), the main spring (phosphor bronze) and the two pivot =
flexure assemblys (with presumably 6 total pieces) are of quite some =
curiosity.  Of what material, size/s, thickness are you guys using?  =
Some of the flexures shown almost look
  like cut thin flat spring steel from the photo.

  Take care, Meredith=20


  On Fri, Aug 14, 2009 at 10:51 AM, Brett Nordgren =
 wrote:

    Meredith,

    We certainly don't want to be accused of torture, though we'll =
gladly plead guilty to some discreet teasing.

    For a little more tease, see   =
http://bnordgren.org/seismo/FBVert01.zip    a photo and a couple of =
sketches.  The photo shows a slightly earlier configuration, but is =
basically what Dave is running now.

    We want to go slowly in regards to encouraging folks to start trying =
to make something like this until we feel we're able to do our part to =
help with any problems.  Building one of these would definitely not be a =
good first project, though I think we are coming to the point where we =
can provide some more detail if there is any particular interest.=20


    Regards,
    Brett










Hi Meredith,
 
The spring is 17-7  stainless =
condition C heat=20
treated to condition CH900. Thickness is 12 mils.  The pivots are 2 =
mil=20
stainless single axis .  Pivot length is only about 12 mils. =
They are=20
held  tension by the C spring. A two axis pivot is not=20
necessary.
 
 
Dave 
 
 

  
----- Original Message ----- 
  From:=20
  meredith lamb 
  
To: psn-l@.............. 
  
Sent: Friday, August 14, 2009 =
17:51
  
Subject: Re: Real time =
traces
  


  
Hi Brett and Dave,
  
 
  
I'am "assuming" the "2" instruments is really the one ~ same ~ =
vertical=20
  (?), with either mechanical changes and/or
  
feedback changes?
  
 
  
As usual (for me), the main spring (phosphor bronze) and the two =
pivot=20
  flexure assemblys (with presumably 6 total pieces) are =
of quite some=20
  curiosity.  Of what material, size/s, thickness are you guys =
using? =20
  Some of the flexures shown almost look
  
like cut thin flat spring steel from the photo.
  
 
  
Take care, Meredith 


  
On Fri, Aug 14, 2009 at 10:51 AM, Brett =
Nordgren <brett3nt@.............>=20
  wrote:

  Meredith,

We certainly don't want to be =
accused of=20
    torture, though we'll gladly plead guilty to some discreet=20
    teasing.

For a little more tease, see   http://bnordgren.org/seismo/FBVert01.zip   =
 a=20
    photo and a couple of sketches.  The photo shows a slightly =
earlier=20
    configuration, but is basically what Dave is running now.

We =
want to=20
    go slowly in regards to encouraging folks to start trying to make =
something=20
    like this until we feel we're able to do our part to help with any =
problems.=20
     Building one of these would definitely not be a good first =
project,=20
    though I think we are coming to the point where we can provide some =
more=20
    detail if there is any particular interest.=20
    

Regards,
Brett