williaty

I'm looking at retrofitting another commercial trailer frame with a floor to make it useful for cargo hauling. I've used 1/4" thick HDPE sheet before and it's been bombproof, as well as completely uncaring about weather and road salt. However, it's HEAVY. Does anyone have a suggestion for a material that has as good or better stiffness than 1/4" HDPE, still is completely unaffected by the weather, yet weighs less?

Yes, I realize I could spend a million dollars and make a honeycomb-core carbon panel. No, I'm not willing to do that.

flangehead

Stiffness at what scale? I used shelving material which has about 1” of section along one edge. The overall assembly is stiff. For point loads I cover it with 1/4” plywood.

see:

https://www.bikeforums.net/21220581-post693.html

spclark 

You're right, solid HDPE is heavy. Not cheap either, but fully 'recyclable' and bombproof.

With this project you describe, is there to be something under the surface that'll see wear and tear from cargo? Untextured HDPE itself is kinda slippery & 1/4" won't support pallet jacks for long without something thicker underneath.

Polypropylene is stronger, weighs less but costs more than similar thickness HDPE. Depending on how long you want to use this trailer you may be able to shave some weight using PP over HDPE or hardwood-planked trailer subfloor. In any event I'd look for sheeting with some texture for safety if you expect to be working in wet conditions.

I-Like-To-Bike

Will your cargo be packages or overpacked? If so, what is the purpose of an extra stiff floor? My DIY trailer floor uses rubber straps stretched across the trailer frame covered by cardboard and has carried much cargo and yard waste for over a dozen years w/o any problem.

See:
DIY bike trailer floor

williaty

It's a utility and touring trailer, so in the long run it'll have just about everything in it. I figure if I eventually wear out the bottoms of packs from stuff chafing against the fabric on the inside, I'll eventually wear out the trailer bottom fabric too. I'm just trying to get ahead of that problem.

TC1

6061-T6 is two orders of magnitude stiffer than HPDE, and only 3 times denser. There are good reasons why aircraft are built from aluminum, and not HPDE. For almost any question seeking a light and strong material, aluminum is a good answer.