Iím looking at putting a longer axle on an ĎA Frameí catamaran trailer to allow it to carry the folding trimaran shown in the first picture below. Existing trailer is second photo. The distance between the outside of the trailer guards is only 1670mm which seems somewhat narrow for the raised floats. The total weight of the boat is approx. 300kg, including floats of approx. 60kg each.

The option Iím looking at is to use a Ďbolt oní rectangular frame as shown in the third picture below which would be bolted with U-Bolts onto the existing rectangular frame where the springs are currently attached. The springs would then be relocated to the new frame. Bolting rather than welding would allow the new frame to be removed if the trailer is required for another boat which would not be very often, but also to avoid potentially damaging the existing trailer frame by welding.

Iím thinking that the distance between the outside of the guards could be increased by say 500mm to 2,170mm with the new frame being around 1700mm x 900mm made from 50x50x3 RHS. This would reduce the overhang of the floats to only 165mm per side.

My question is whether there are any structural issues with this approach i.e. using U Bolts rather than welding or bolting through the two frames, dimensions of new frame etc. and if members have any suggested improvements or recommendations e.g. should U-Bolts be vertical or horizontal.

Any feedback would be greatly appreciated.

Attached Images

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