Randy,

The configuration of the small and large coils and magnet assemblies is for
the coil to move in/out through the wide dimension. The idea is that this
would be used for a vertical seismometer.  That's a good idea to modify the
voice coil magnet.

Gary

 

From: psn-l-request@.............. [mailto:psn-l-request@............... On
Behalf Of Randy Pratt
Sent: Thursday, November 27, 2008 7:23 AM
To: psn-l@..............
Subject: Measuring Newtons/Amp

 

Hi Gary,

 

On the small neo magnet photo it appears the magnets are 90 degrees turned
from what I would think to locate them.  Did you try the other orientation?

 

I have used several speaker magnets.  On most the 4 bolt holes do not go
through the magnet ring itself.  If you insert and tighten longer threaded
bolts against the magnet, the pole ring will pop loose and then you can
easily turn the gap wider to probably 1 cm or more on that magnet.  Even if
it won't come loose it is fairly easy to open the gap on a lathe but be
careful of the turnings as they are very sharp and the magnetic field tends
to align them into finger cutting angles.  Extending the center pole into
the coil with a short fat bolt after the gap is widened also seems to
increase output.  

 

Randy














Randy,

The configuration of the small and large coils and magnet
assemblies is for the coil to move in/out through the wide dimension. =
The idea
is that this would be used for a vertical seismometer.  =
That’s a
good idea to modify the voice coil magnet.

Gary

 





From:=

psn-l-request@.............. [mailto:psn-l-request@............... On =
Behalf
Of Randy Pratt

Sent: Thursday, November 27, 2008 7:23 AM

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

Subject: Measuring Newtons/Amp





 



Hi
Gary,





 





On
the small neo magnet photo it appears the magnets are 90 degrees turned =
from
what I would think to locate them.  Did you try the other =
orientation?





 





I
have used several speaker magnets.  On most the 4 bolt holes do not =
go
through the magnet ring itself.  If you insert and tighten longer =
threaded
bolts against the magnet, the pole =
ring will pop loose and
then you can easily turn the gap wider to probably 1 cm or more on that
magnet.  Even if it won't come loose it is fairly easy to open the =
gap on
a lathe but be careful of the turnings as they are very sharp and the =
magnetic
field tends to align them into finger cutting angles.  Extending =
the
center pole into the coil with a short fat bolt after the gap is widened =
also
seems to increase output.  





 





Randy<=
o:p>