outboard crane at stern

[blue-max]

missed a chance to  buy  someone's cast  off which was perhaps no  bad thing as getting it to  the boat would have been difficult, but been having thoughts about the design for some time. What I would like to  do  is to  use standard stainless tube fittings and make it  out of 25mm  pipe for the vertical and horizonal and bracing pieces. I wonder if 25mm tube would be strong enough ; wall thickness could be 2mm and perhaps lined with 22mm tube to  avoid bending. Outboard not that heavy 3.5 hp but the crane arm needs to  be about 80 cm. Any thoughts?         

[Yngmar]

Will need a diagonal support in the bend, else it is probably too springy.

[Happysailor]

I would consider making it (having it made) out of 40mm tube to get a cleaner look and feel. To make it out of 25 mm tube will be way too flimsy in any direction to lift your outboard.. (especially if you like 80 cm outreach)

[blue-max]

I've got some pipe at home and fittings for 25mm so will test in the garden with a weight on the end of the arm  and see how much deflection there is