Hello Meredith, Dick, Chris I rechecked the wire hinges coming from =
mine. I do not have a micrometer, but there is one wire per hinge =
(black) which is relatively rough and not shinny like piano wire but =
just as springy. I suppose it is steel wire and smaller in diameter =
than that used for a paper clip. Now, I am beginning to under stand =
that this must not be original to the unit and should be a flat flexible =
hinge instead. Perhaps that is the reason I have been having so much =
trouble getting the seismometer boom to remain centered. =20
James Allen
----- Original Message -----=20
From: meredith lamb=20
To: psn-l@.................
Sent: Tuesday, August 19, 2008 9:29 PM
Subject: Re: SPRENGNETHER 201 LONG PERIOD VERTICAL SEISMOMETER
James,
Am sure your round wire hinges (one per each hinge, or more?), that =
whomever had the vertical before you substituted the round wire they =
had, for the (probably
broken) original flat springs therein. Evidently yours works ~ as is. =
Mine came with similar round piano wire/s; but they had like 4 wires of =
~ 0.025" diameter;
per each of the two hinge clamps (eight total), which I replaced with =
flat springs....which also ~ worked...but, I still don't know the =
original flat spring width/thickness.
Its interesting the variation of wire/flat springs that do work....but =
whether they are really even near ideal is literally unknown. If this =
spring pivot spring is too stiff/thick, the
mass response won't be as enertially responsive as it ideally should =
be. =20
Your second sentence below leaves me pondering whether its some ~ (not =
a normally spring) metal rod/s used? It should be 0.025" diameter piano =
wire....for initial setup flexuring=20
that it will go through in the process, and for simple high strength =
when the spring is strung. I suppose you could use all the loose =
locking 1/4" rods to hold the boom;
and use a fine file edge (single light stroke) to see if it very =
strongly resists filing like piano wire does, or; is relatively ~ easily =
filed like iron etc. Another clue;
piano wire is ultra smooth; a typical metal rod will feel like a drag =
on your fingers when lightly run over. "IF", the "straight length" you =
mention is bigger than 0.025",
the previous owner may have removed acouple parts to accomodate their =
"reengineering"....and you have to live with such.=20
Take care, Meredith
=20
On Tue, Aug 19, 2008 at 6:59 PM, JAMES ALLEN =
wrote:
Meredith and Dick
My Spremgnether has two hinges made out of wire and looks like thick =
piano wire about 3/4 the thickness of pencil lead. Additionally, =
instead of wires being attached to each ends of the spring attachments =
each end of the spring has a straight length that goes into the =
adjustment nuts.
James
Hello Meredith, Dick, Chris I =
rechecked the=20
wire hinges coming from mine. I do not have a micrometer, but =
there is one=20
wire per hinge (black) which is relatively rough and not shinny like =
piano wire=20
but just as springy. I suppose it is steel wire and smaller in =
diameter=20
than that used for a paper clip. Now, I am beginning to under =
stand that=20
this must not be original to the unit and should be a flat flexible =
hinge=20
instead. Perhaps that is the reason I have been having so much =
trouble=20
getting the seismometer boom to remain centered.
James Allen
----- Original Message -----
From:=20
meredith lamb
Sent: Tuesday, August 19, 2008 =
9:29=20
PM
Subject: Re: SPRENGNETHER 201 =
LONG PERIOD=20
VERTICAL SEISMOMETER
James,
Am sure your round wire hinges (one per each hinge, or =
more?), that=20
whomever had the vertical before you substituted the round wire they =
had, for=20
the (probably
broken) original flat springs therein. Evidently yours =
works ~=20
as is. Mine came with similar round piano wire/s; but they had =
like 4=20
wires of ~ 0.025" diameter;
per each of the two hinge clamps (eight total), which I replaced =
with=20
flat springs....which also ~ worked...but, I still don't know the =
original=20
flat spring width/thickness.
Its interesting the variation of wire/flat springs that do =
work....but=20
whether they are really even near ideal is literally =
unknown. =20
If this spring pivot spring is too stiff/thick, the
mass response won't be as enertially responsive as it ideally =
should=20
be.
Your second sentence below leaves me pondering whether its =
some ~=20
(not a normally spring) metal rod/s used? It should be 0.025" =
diameter=20
piano wire....for initial setup flexuring
that it will go through in the process, and for simple high =
strength when=20
the spring is strung. I suppose you could use all=20
the loose locking 1/4" rods to hold the boom;
and use a fine file edge (single light stroke) to see if it =
very=20
strongly resists filing like piano wire does, or; is relatively ~ =
easily filed=20
like iron etc. Another clue;
piano wire is ultra smooth; a typical metal rod will feel =
like a=20
drag on your fingers when lightly run over. "IF", the =
"straight=20
length" you mention is bigger than 0.025",
the previous owner may have removed acouple parts to accomodate =
their=20
"reengineering"....and you have to live with such.
Take care, Meredith
On Tue, Aug 19, 2008 at 6:59 PM, JAMES ALLEN =
<jcallen1@...........> wrote:
Meredith and Dick
My Spremgnether has two hinges made =
out of wire=20
and looks like thick piano wire about 3/4 the thickness of pencil=20
lead. Additionally, instead of wires being attached to =
each ends=20
of the spring attachments each end of the spring has a straight =
length that=20
goes into the adjustment nuts.
James