[quote=GM;611857
I replaced the tow bar with a 2" stainless steel tube with a slightly
thicker wall. The added weight was neglible. I also ran a loop of
stainless steel cable through the inside around the bolts connecting
the tow bar to the trailer and those connecting the coupler to the
bar. Should the tow bar break, there is still the cable inside, which
will keep the trailer from completely getting away and wandering off
into the oncoming traffic.

Safe flying and trailering

U. Neumann[/QUOTE]


The cable is a great idea!
The choice of stainless, however, I wouldnt take. Stainless will work harden from continual heat/cool cycles or vibration (like every bump you go over) and crack at the stressed points.

Please check your stainless bar on a regular basis at its stressed points for VERY small cracks, once there, they will grow and split, probably on the same trip. The section will fail under tension, not compression.

A better choice of towbar material would be mild steel with a heavy galvanic (hot dip) coating. The wall section does not have to be that heavy, its better to use a larger section, especially in the vertical direction. Do not seal the ends before gal dipping, this will ensure the coating goes inside as well and leaves a great protected spot for wiring runs. Do not weld to the assembly after gal dipping.

If this style of towbar/tongue needs to be retrofitted to an existing trailer, use as many bolt points as possible to reduce the stress point.

Bagger