I've recently encountered a problem with my aluminium trolley, which I'd like to highlight in case anyone else has the same issue.  One of my cradle supports snapped just above where it is welded onto the main axle beam and, on closer inspection, the other side was also showing clear signs of stress cracking.

If this had failed whilst towing, it's likely the cradle would have parted company with the trolley and this clearly would not be good for the hull.....

The trolley is only 3.5 years old and was built by one of the well known Merlin trailer suppliers.  The fix wasn't too bad, it cost me about £50 to have our local TIG welder replace the original 3/4" cradle supports with some much more substantial ones, plus also replace the axle stubs which were looking very worn.