I have been helping Mr Rezarf with his carrier, and i was partly the cause of going with the 3/16" steel. I think it IS plenty strong, and it it much easier to weld properly, which is where the parts would fail if they are going to fail. I checked this with both the folks down at the steel yard and my welding teacher, who has 30+ years in the fabrication business. Both said this would be more than enough for 200lbs.
My 4Runner's frame is only 3/16" thick, and it's been doing fine so far.
Rezarf is also spreading the weight over 4 3/8" brackets, and the swing arm will be supported by nylon buffers on the opposite end as the spindle and in the middle so less stress is placed on the spindle. He's also got some good friends who can help him weld this baby, so he'll be fine.
My 4Runner's frame is only 3/16" thick, and it's been doing fine so far.
Rezarf is also spreading the weight over 4 3/8" brackets, and the swing arm will be supported by nylon buffers on the opposite end as the spindle and in the middle so less stress is placed on the spindle. He's also got some good friends who can help him weld this baby, so he'll be fine.