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<DIV>In a message dated 1/3/2013 12:52:34 A.M. Eastern Standard Time,
jaransont3@comcast.net writes:</DIV>
<BLOCKQUOTE
style="BORDER-LEFT: blue 2px solid; PADDING-LEFT: 5px; MARGIN-LEFT: 5px"><FONT
style="BACKGROUND-COLOR: transparent" color=#000000 size=2 face=Arial>On Jan
2, 2013, at 11:57 PM, Jim Adney wrote:<BR><BR>> On 2 Jan 2013 at 22:13,
John Jaranson wrote:<BR>> <BR>>> With this in mind, here is a drawing
of my latest plan....<BR>>> <BR>>>
http://www.carartbyjohn.com/2013JaneBuild/Type3AirRide.jpg<BR>> <BR>>
That puts some additional side force on the inner journals:force that <BR>>
wasn't there before. You may need to beef up that bearing a bit.<BR>>
<BR><BR>Good point. I will look into making the thrust bearing also a
rotational bearing and add a thick doubler to the support bracket.<BR><BR>>
I see that you've cut windows in both the front and back of the beam, <BR>>
but you really only need them in front. Welding metal over the rear <BR>>
cutouts would put some strength back in there.<BR><BR>That is just an old
rusted out beam that I am using as a mock-up/exploratory surgery victim.
The final beam would only have a cut-out on the front side. I would also
add a doubler plate around the opening to beef it up. It would also hold
a couple of rubber flap seals to keep most of the water out. I will have
to provide a couple of drain holes for the water that will inevitably get in
there.<BR><BR>> <BR>>> Basically this eliminates the lower torsion
bars and replaces each with its own airbag. The airbags would be mounted
between a bracket attached to the beam (not shown) and the bag arm shown in
yellow. This arm is attached to the inside end of the trailing arm
through a custom adapter insert. The added thrust bearing acts on the
bushing support already in the beam assembly shown in this
picture...<BR>>> <BR>>>
http://www.carartbyjohn.com/2013JaneBuild/Type3AirRide2.jpg<BR>>
<BR>>> I will probably weld the adapter insert along with using the
shear pin just to make sure it doesn't move.<BR>> <BR>> Yeah, I wouldn't
want to trust that shear pin to hold, but you'll <BR>> have to be careful
with the weld, because I suspect the journal there <BR>> is hardened. (And
if it is hardened, welding could cause problems in <BR>> the adjacent
HAZ.)<BR><BR>Yeah the heat affected zone is a concern. I have also
thought about machining some castellations in the end of the trailing arm and
matching ones in the adapter to mechanically transfer the torque. The
shear pins job would then be to counter the much smaller thrust
loads.<BR><BR>> <BR>> You really need something to securely hold your
new inner arm from <BR>> coming loose from the torsion arm. Maybe a big set
screw in a dimple <BR>> will be sufficient, but it needs to be thought out
carefully. You'll <BR>> probably want to put a radius where the adaptor
goes from round to <BR>> square, to try to make sure it doesn't shear off
there. <BR><BR>Have also considered using a hexagonal pin instead of
square to reduce the stresses at the transition. A big radius there will
also help with the transition. I have also consider slotting the end of the
arm and putting a clamp bolt in there.....not unlike the clamp bolt that holds
the ball joints in.<BR><BR>> <BR>> Interesting concept. Will this stick
into the spare tire well, or <BR>> will it clear to the sides? (Or does
that well even exist on the Lead <BR>> Sled?)<BR>> <BR><BR>It will
certainly stick into the bottom of spare tire wheel. The top of that
well is one of the places I have been considering for the air tank and air
compressor. The spare tire will just sit on top of the fuel tank,
probably on a bracket.</FONT></BLOCKQUOTE>
<DIV> </DIV>
<DIV>John, are you looking at using a wire EDM to put the hole in the trailing
arm for the shear pin? I'm only asking, as that part of the trailing arm should
be hardened steel. I think it might be better to go out the full distance, and
grab the end of the trailing arm like the stock set up, and maybe set up a
pillow block next to the end of the air bag arm, so you're not twisting the end
of the shaft off. I do like the concept, but setting up the trailing arm shaft
assembly is still going to need a little more thought, as you only have so much
room to play with, and the trailing arm is splined. You might want to see about
doing some 3D animation on it, along with a little stress testing. ;-) Nice
concept though, and it might just work. : )<FONT
style="BACKGROUND-COLOR: transparent" color=#000000 size=2 face=Arial><BR>
<DIV> </DIV>
<DIV><FONT lang=0 size=2 face=Arial FAMILY="SANSSERIF" PTSIZE="10">Bob 65 Notch
S w/Sunroof and IRS aka Krusty<BR>64 T-34 Ghia aka Wolfie<BR>71 Square-vert
under construction</FONT></DIV></FONT></DIV></FONT></BODY></HTML>