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When
I pulled off the front suspension a while ago, I just put the whole mess
into a plastic crate in my shed. Now, cleaning off 35+ years of gunk,
I found that the lower a-arm was cracked around the fulcrum pin mounts.
What to do? I could find anothe pair of a-arms, replace the fulcrum pin
mounts and fulcrum pin and hope that they won't develop any cracks in
the future,.....or......I could make my own lower a-arms. |
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These arms
are very light stamped steel and have no provisions for front anti-sway
bars, nor do they offer a decent mounting location for a tube-shock conversion.
(more on that later) |
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First order
of business was to make a jig from the existing non-cracked a-arm. This
way I could positively and accurately locate the inner pivot points and
the fulcrum pin mounting points and the spring pan location. Then, since
the inner pivot tubes on the a-arm are tapered in the center, I cut them
out of the A-arms. |
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The tapered
inner pivot tubes are pretty thin, and even though they would work in
the stock a-arm, I decided to surround them with a thicker tube. Using
thick walled DOM tubing, I turned the inside diameter to match the outside
diameter of the inner pivot tubes, then drilled some holes in them to
allow a plug weld to help secure them to the tubes. The tapered pivot
tubes were pressed into the DOM tubing, then welded around each end
and welded in the drill hole, then I faced both ends of the assembly
to the proper length. |
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The fulcrum
Pin mounts presented the same problem, so I took some 1" DOM tubing
and turned the inside to the diameter of the fulcrum pin mounts. |
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Then, using
the same technique as above, I drilled holes in the DOM tubing to plug
weld the fulcrum pin mounts to the DOM tubing to produce a strong, secure
assembly |
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Here's the
A-Arm jig in the vise. It is made of .120 wall rectangle tubing. |
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The tubing
notcher cutting a notch in the 0.120" wall 1" o.d. DOM tubing
that I am using for the A-arm. I figure since this material is strong
enough to support the front of a full-size car under dirt-track race conditions,
then it is certainly strong enough for the little Mite |
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Mocking up
the tubes in the jig... |
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Here's the
collection of cut and beveled tubes that will make up 1 A-arm. |
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this is a
mock up of the A-arm before welding. After this is welded together, I
have to make a mount for the spring pan and then for the sway bar. I'll
figure out a tube shock mounting point after I get the whole front suspension
and brakes figured out. |
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And
here they both are, welded and ready for the spring pan. |
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Close
up of the tig welding on the cross brace. |
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This is the completed arm
with spring pan welded in. I used the top of the stock spring pan and
cut a hole in the thick steel of the spring mount and welded it in. |
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Here's
the arm on the car. Everything fits and moves correctly!
Phase two will be making the new upper arms to get rid of the non-working,
sloppy armstrong lever shocks. Stay tuned! |