<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML><HEAD>
<META http-equiv=Content-Type content="text/html; =
charset=iso-8859-1">
<META content="MSHTML 6.00.2800.1264" name=GENERATOR>
<STYLE></STYLE>
</HEAD>
<BODY bgColor=#ffffff>
<DIV><FONT face=Arial size=2>Thanks for the input. What other =
specifics might
you have in mind?</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I think recycling metal is an excellent =
ideal to
pursue. But sometimes you just need what you need. I usually go to =
</FONT><FONT face=Arial size=2><A
href="http://www.metalsupermarkets.com/">http://www.metalsupermarkets.c=
om/</A> .
Great place. They have anything you might want and will cut to your =
specs. Just
order, load up your trunk, and assemble your jig (well, almost that
easy).</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Terry Farrell</FONT></DIV>
<BLOCKQUOTE
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; =
BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: =
black"><B>From:</B>
<A title=Crashvalve@aol.com
href="mailto:Crashvalve@aol.com">Crashvalve@aol.com</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A =
title=pianotech@ptg.org
href="mailto:pianotech@ptg.org">pianotech@ptg.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Monday, November 10, 2003 =
7:54
AM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: Steel/Jig =
Strength</DIV>
<DIV><BR></DIV><FONT face=arial,helvetica><FONT face=Geneva =
color=#000000
size=2 FAMILY="SANSSERIF"><BR>In a message dated 11/10/03 7:17:11 =
AM, <A
href="mailto:mfarrel2@tampabay.rr.com">mfarrel2@tampabay.rr.com</A>
writes:<BR><BR><BR>
<BLOCKQUOTE
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #0000ff 2px =
solid; MARGIN-RIGHT: 0px"
cite="" TYPE="CITE"></FONT><FONT face=Geneva color=#000000 =
size=2
FAMILY="SANSSERIF"><BR><BR><BR></FONT><FONT face=Arial =
color=#000000 size=2
FAMILY="SANSSERIF">I've made myself a little pneumatic contraption =
for
laminating ribs. I seem to have just about everything worked out for =
proper
function (actually, works quite a bit better than I had =
hoped!) except
for some excessive jig flex. I have =
a 1.5-inch-thick Delignit
pinblock incorporated into the jig for stiffness, but I =
still seem to
be getting several millimeters of flex in the middle of the 5-foot =
long jig
when I pressure up. So I think the solution is to put a couple =
of angle
irons, or steel channels along the length of the jig. This thing is =
getting
VERY heavy, so I prefer to not use any more steel than =
needed.</FONT><FONT
face=Geneva color=#000000 size=2
FAMILY="SANSSERIF"><BR><BR></BLOCKQUOTE></FONT><FONT face=Geneva =
color=#000000
size=2 FAMILY="SANSSERIF"><BR><BR>I've no science background, but =
i've made
numerous structural steel jigs.<BR>My first jigs used steel as a =
monoblock
material, a "one piece big enough to resist" approach.<BR>That is off =
target.
What you want is a little teeny bridge structure. In other words, =
multiple
pieces of steel with lots of triangle shapes for rigidity. This way =
there is
not too much mass, but great rigidity. If you don't want this large =
"fab" job,
use a steel channel or even an "I" beam, but then it will be heavy; I =
store my
big jigs outside and paint them. A necessity after my first 14 foot =
long
soundboard jig. BTW don't order steel from your friendly supplier, =
check the
scrapyards for material. You can't pick and choose as much, but it's =
way
cheaper. You may consider this close to dumpster diving, but It is =
invaluable
to the machine builder. At the scrapyard you don't worry so much about =
the
calculations, just buy way over what you need, and start an outside =
storage
rack area. If you start fab work like this, access a sawzall for cuts, =
or a
torch. A resinod cutting disc in a tablesaw is a BAD idea. If you have =
specifics shoot them back, happy to answer from no-training and 12 =
yrs. of
practical experience.<BR>Glenn C.</FONT><FONT face=Geneva =
color=#000000 size=2
FAMILY="SANSSERIF"></FONT> </FONT></BLOCKQUOTE></BODY></HTML>