At 10:02 AM 5/10/02 -0400, Mike Razor wrote:
>The bow broke at the spot weld at the curve where the two screws are
>suppose to hold it together.
If you want to go for original strength, then it needs to be welded, and JB
Weld won't do it. Look for a small industrial machine shop that does
job-shop work and small lots for one of a kind production machinery. They
should have a TIG welder and the talent to use it. The TIG welder can make
a clean weld as strong as the parent material, even in thinner materials,
and it can be ground smooth and painted so you may never know it was
broken. You will have to remove the parts from the car and take them to
the shop, and it will likely cost at least $50 for a minimum shop labor charge.
>The holes are enlarged and the screws no longer bite and then the weld
>gave way. It took some tugging on my part to break the weld, .... I have
>smeared JB weld on both parts of the bow and at the weld,
Wait a minute. Are you saying that the bow tubing did not break, but that
only the screws and spot welds gave way? If the curved tubing is not
broken, then JB Weld may very well work to hold the parts together. It
needs a fairly large surface area in the glue joint to have high holding
capacity. If you can fill the entire gap between the tubular bow and the
flat strap end frame and clamp the parts together while it cures, that
should do it.
>also reinserted the two screws that were loose, in an attempt to keep the
>holes clear and may try to go back and get larger screws that may cut
>through the JB weld.
The screws thread into the thin wall of the tubing at that point and only
get a grip for one or two turns of the thread. JB Weld would probably not
hold the thread in that short a length of engagement, and the tubing wall
is too thin to hold a Helicoil. However, if you can stuff the inside of
the tube full of JB Weld before installing the screws, and also coat the
screw threads with JB Weld before installation, then they might hold okay
(just don't expect to ever remove them again). Alternately you might fill
the tube with JB Weld, and after it cures try drilling and tapping threads
there for the screws. The screws alone will not hold the stress, but it
should work in conjunction with filling the joint between the parts with JB
Weld. In fact if you do the screws first, then the screws may be
sufficient to hold it together while the JB Weld in the larger joint sets up.
Barney Gaylord
1958 MGA with an attitude
http://www.ntsource.com/~barneymg
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