Originally Posted by feudalkaos
I was mistaken, the cross member
Attached are 2 more pictures showing how the dinghy
Your drawing makes it look like the dinghy
load is fully cantilevered, in which case the hole is in a very bad location. It looks like there are wires helping to support the solar panels
(and putting them under a bending load -- trying to break them?). Perhaps these actually go directly to the davits
instead? If those wires are of adequate size and go directly to the davits
, then the cantilever is relieved, and the hole becomes less of an issue.
I like the suggestion of welding in a piece of tube to reinforce the hole. Unfortunately this requires a skilled welder. Another possibility is to fit a doubler around the hole, with the doubler welded all around. (And the hole in the doubler could be smaller than 1 1/8). (Be aware that a bad weld can make the whole thing weaker rather than stronger.)
But I'm afraid I'd really have to see this and apply a load and see the reaction. If you were to test load the system, you'd want to assume a flooded dinghy (1000# at least) multiplied by accelerations from wave action (maybe 2G for a sail boat
and 4g for a power boat
Also be aware that I would not even consider trusting advice
(such as mine) from the internet
on a project
like this. I'd want to do all the math myself, or hand it over to someone who I trust to do so.
You could calculate the force at the hole by using the leverages involved. You might find that the aft side of the tub is being crushed under a load of 20,000 lb. Stick a piece of 2" tube (with hole drilled) under a press with that load applied (whatever it actually works out to be) and see what happens.