Outer Limits 4x4 Board

i bought this as a project to build up/modify for my yacht but im unsure how to go about it..
its 75x75x4 or 5mm and looks ok but the section that the springs are attached to, will probably need to be replaced ..





il need to extend the drawbar and also extend the rear to cover the boat fully..

its 21ft total length and the yacht is 26ft


with my measurements il need to extend it by 2800mm total



how far can i extend the drawbar? without extra bracing?

or if i went 75x75x6mm would it help?

anyone know any places in shitney i should look at to get prices for steel for this??




any help/advice appreciated

This will be a pain in the ass to extend safely.. you are better off chopping the currant drawbar off, extending it from 1 piece of metal each side to your required length (minimum 75x50x3), then add bracing and move your axles up further towards the middle.

cheers mark.

75 x 75 x 6 about 12kgs per meter

metalland or anywhere really should stock this..

Few $$$ though...

You'll be better off extending the back of the trailer and moving the the axels back, then you wont have to touch the drawbar. Run the new rails on the outside of the current rails and about 300mm past the axel section.

Grant

mud4b wrote:This will be a pain in the ass to extend safely.. you are better off chopping the currant drawbar off, extending it from 1 piece of metal each side to your required length (minimum 75x50x3), then add bracing and move your axles up further towards the middle.

cheers mark.

i was going to unbolt it and use some thicker box section, would that work?
first pic doesnt show it properly

would going 75x125 be better for strength with the longer length? or stick with 75x75 and go thicker?

Is that a dry dock launching trolley or is it a proper road going trailer with springs (I can't see any springs on there)? Plenty of people at our yachty use the launching trolleys purely for getting the boat in and out with less maintenance than a true road going trailer.

If you're going to make that into a road going trailer for a 26ft trailer sailer (I think that's what you said), I'd be widening the chassis rails and getting the spring hangers as far outboard as possible.

What sort of yacht are you putting on it? Many trailer sailers can be loaded on trailers with massive unsupported rear over hang. I've got a Masrm 720R and the last cross member is nearly 2000mm from the transom.

Depending where your pivot point is, you could probably get away with your original plan of replacing just the SHS single drawbar in a longer and thicker length.

Not sure if any of this has helped. It might be easier if you show us a picture of your boat.

Cheers


Anthony.

Be really careful....old boat trailers very commonly rust from the inside out.......
If the metal is gal, the welds are usually the problem..... the only time I ever tried to mod a trailer like this I soon worked out it was far cheaper to build a new one.....
A lot of steel places have specials or clearance stock...ring around.
The last time I did I brought 3k worth of steel for 1.4k.... nothing wrong with it other than the blue paint was faded...