Need help with 18' x 8'6" trailer frame

[e.gordon]

Ok as a millwright i spend most my time working out of a trailer. well its come to the point where my trailer is too small. rather than buying my trailer i figured it would be more fun to fabricate it. my dimensions are 18'L x 8'6" W. My questions are:
1.) What should i use as far as material for the frame?
2.) How many cross members should i use?

 

[shenion]

Hard to say as you do not say the load capacity of the trailer.

I'd say find one similar and take a look.

 

[pedrobedro]

Do some research before you start anything. What weight will you be loading it to and what are you towing it with ? You could adapt an articulated lorry trailer at the size you are looking at there.

 

[shenion]

Being in the US, I doubt he will worry about UK regs.

It is pretty lax here; my trailer is registered as home-made. Took nothing more than a bill of sale.

 

[e.gordon]

about my trailer

I need it to be able to support 6000 to 8000 lbs

 

[bigegg]

Usual [1] advice is go look at some trailers of the size your'e wanting to make, and see how they're made.

I would hazard a guess you're gonna want something like 8in x 4in x 3/8in channel for the beams, 4in x 2in x 1/4in channel on 16in or 24in centres

[1] I say "usual" advice - sensible advice is something else, and goes "If you have to ask, you don't know enough to make something which could potentially kill people"

 

[BuiltnotBought]

so it appears one question was over looked, the material. I have, as it happens just been discussing with my boss a trailer we need making. We are having it made off of an ally chassis and capable of carrying two Suzuki swifts ... 2.5ish tonnes I think. but the trailer only weighs 800kg. Though we have managed to drop that even more by dropping it to a twin axel and alloy wheels. "every little helps"

I can try find out chassis thickness and dimentions if you want. This is a flat bed with a cover. So cars can be transported without being seen.