Here's a pic of my so called difficult set up on another post
Just ask Tony.....
Small bottom chain is connected to the bottom hole of boat and connects to the winch tower just below the winch with shackles.
I then run a triangular chain set up to either side of the trailer rails with shackle and a centre turn buckle to fully tighten up the rig with lock nuts as it tends to work loose on bumpy roads like the one to 1770.
This also holds the bow down.
Solid as once tightened up.
You will find that most fatigue fractures occur directly besides a weld as the weld is generally stronger than the metal being welded and the metal also tends to loose some of it's original design strength due to the heat of the weld.
Your photo demonstrates that.
I would be more inclined to check around welds on your trailer for signs of fatigue cracks.
Cheers Rob.
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Safety Chain Set Up.jpg