Thread: Triathlon trailer

Everyone likes a trailer build.

Originally Posted by easo

Everyone likes a trailer build.

No probs.

are the rails 150x50? how thick?

Yes the rails are 150 x 50 x 4, the crossmember's 150 x 50 x 3 and the drawbar 150 x 50 x 5.

That is some heavy duty material. I was going to do a car carrier with 2.5 and 3mm. Might have to reconsider.

If you do the main rails from 75 x 50 x 4 and the drawbar from 100 x 50 x 4 it will be extra extra strong. When you put the sides on the car trailer it produces a truss structure and this makes it extremely rigid. The triathlon trailer does not have this in a way that acts directly on the chassis rails, so needs very strong chassis rails to minimise flexing with such a large rear overhang. I also like the main rails to be heavy in the wall thickness to insure the suspension mounts don't pull out which they will do with a light wall, so unless it's a 750kg box we normally don't use 3mm wall main rails and never 2mm for them.

Simon
did you consider using structurals for the rails like PFC?
will you ladder truss the ain chassis rails?

S

Originally Posted by roverrescue

Simon
did you consider using structurals for the rails like PFC?
will you ladder truss the ain chassis rails?

S

Interesting point that brings us back to the good ol' days of trailer design and flashbacks of the RHS Vs Angle debates. I hadn't really thought too much about it to be honest. There is a hire trailer getting around here with a channel drawbar which I have looked at sceptically, but admittedly it's not bent. I guess I've generally preferred RHS type sections because I've always thought that it transfers forces efficiently throughout the structure in a number of ways and its easy to intersect with other members - but thats not to say that PFC's haven't been designed to be as good or better.

Just doing the ladder trusses as we speak. Heavy buggers, I can barely lift each arm of the drawbar - perhaps I need more gym time! Still haven't worked out how I'm going to flip the chassis! I think I'll be upsidedown welding instead.

Oh! Brainwave....... weld the mounts onto the chassis rails then the chassis together. Drawbar onto the front crossbar and then the crossbar into the chassis rails. Ok, problem just solved, thanks Steve!