Hi Chris,

I quite readily agree with you; that they are a very lower grade steel for
the much higher desirable permeability aspect.  Those that can; will indeed
get better iron/steel.
Personally, I've got all the even much better iron/steel, and I don't need
any improvements in such material for myself.  They are a "beginner"
recommendation I think
that would work more immediately in their "first step" more simpler
seismometer projects.  I'll try to express myself better in the future.

In the basic sense of a usual "typical very small or 3rd world budget" (read
it as a high failure rate for most individuals in their often brief
seismology hobby interest)
approach; they are relatively impossible to beat economically price wise,
immediate much wider range of mechanically functionally and still get useful
results
in coil pickup and dampening needs.  I would guess; they are probably size
limited to their usefulness to seismometers where the vertical or horizontal
mass is
light weight like around 1 pound; but even here the very choice of the
neodymium magnet dimension size, and their very choice of the grade of the
magnet used
will likely have a dramatic impact on the results observed.  There is alot
of other problems in seismometry construction; but hopefully this could
reduce one piece.

I have the highest regard for your extensive professional knowledge and
opinions Chris; which I think most people are very grateful and appreciative
for.

Take care, Meredith Lamb





On Fri, May 30, 2008 at 10:02 PM,  wrote:

> In a message dated 2008/05/30, paleoartifact@......... writes:
>
> Actually; I think the cheapest metal magnet holding assembly, particularly
> for most of us without the tools to make metal plates; is to just buy a pair
> of machinist "1-2-3" (1" x 2" x 3") blocks from like, Discount machine on
> E-Bay.
>
>
>
> Hi Meredith,
>
>        These are hardened steel blocks. They will have a significantly
> lower permeability than mild steel. I first tried using annealed high carbon
> steel - called gauge plate - you can buy it in a wide range of sizes, but I
> reverted to mild steel.
>
>        We can get hold of the 2" x 1/4" mild steel strip through outlets
> serving the building trade - it is used for reinforcing / joining wood beams
> and also for load bearing lintels. Hinges for farm gates are bent from this.
>
>
>        Regards,
>
>        Chris
Hi Chris,

I quite readily agree with you; that they are a very lower grade steel for the much higher desirable permeability aspect.  Those that can; will indeed get better iron/steel.
Personally, I've got all the even much better iron/steel, and I don't need any improvements in such material for myself.  They are a "beginner" recommendation I think

that would work more immediately in their "first step" more simpler seismometer projects.  I'll try to express myself better in the future.

In the basic sense of a usual "typical very small or 3rd world budget" (read it as a high failure rate for most individuals in their often brief seismology hobby interest)

approach; they are relatively impossible to beat economically price wise, immediate much wider range of mechanically functionally and still get useful results
in coil pickup and dampening needs.   I would guess; they are probably size limited to their usefulness to seismometers where the vertical or horizontal mass is

light weight like around 1 pound; but even here the very choice of the neodymium magnet dimension size, and their very choice of the grade of the magnet used
will likely have a dramatic impact on the results observed.  There is alot of other problems in seismometry construction; but hopefully this could reduce one piece.


I have the highest regard for your extensive professional knowledge and opinions Chris; which I think most people are very grateful and appreciative for.

Take care, Meredith Lamb

 

   

 

On Fri, May 30, 2008 at 10:02 PM,  <ChrisAtUpw@.......> wrote:

In a message dated 2008/05/30, paleoartifact@......... writes:



Actually; I think the cheapest metal magnet holding assembly, particularly for most of us without the tools to make metal plates; is to just buy a pair of machinist "1-2-3" (1" x 2" x 3") blocks from like, Discount machine on E-Bay.




Hi Meredith,



       These are hardened steel blocks. They will have a significantly lower permeability than mild steel. I first tried using annealed high carbon steel - called gauge plate - you can buy it in a wide range of sizes, but I reverted to mild steel.




       We can get hold of the 2" x 1/4" mild steel strip through outlets serving the building trade - it is used for reinforcing / joining wood beams and also for load bearing lintels. Hinges for farm gates are bent from this. 




       Regards,



       Chris