Pirate 4x4 banner

1 - 6 of 6 Posts

·
Registered
Joined
·
564 Posts
Discussion Starter #1
For an aluminum open-car trailer, can I get by with 3003, or do I need 6061 for the deck?

I'm planning on only decking the outside 2 feet (where the tires run), and leaving it open in the middle. Span between cross rails is ~14", and I was planning on using 1/4 thick treadplate, but I supposed cost-wise 6061 in 3/16 is in the ballpark of 3003 in 1/4, so maybe thickness is unclear too... :confused:

Thanx.
 

·
Registered
Joined
·
564 Posts
Discussion Starter #2
Anyone?:confused:
 

·
Registered
Joined
·
62 Posts
I'll play.

Going from 3/16 to 1/4 thickness is going to increase bending strength about 45%. Material specs put 6061's yield strength a little over TWICE that of 3003 (will depend some on the temper of the material), so you're in the same ballpark either way. Having never built a trailer or welded aluminum, based solely on those strength comparisons, I'd pick the 6061 and keep the weight down.

Is that the sort of answer you were looking for?
 

·
Registered
Joined
·
564 Posts
Discussion Starter #4
I'll play.

Going from 3/16 to 1/4 thickness is going to increase bending strength about 45%. Material specs put 6061's yield strength a little over TWICE that of 3003 (will depend some on the temper of the material), so you're in the same ballpark either way. Having never built a trailer or welded aluminum, based solely on those strength comparisons, I'd pick the 6061 and keep the weight down.

Is that the sort of answer you were looking for?
Thanks - that helps a lot.

I guess for me the unknown is how much strength I need - i.e. do I need 1/4 wall 3003 or 1/4 wall 6061? The aluminum supplier I talked to said they usually sell 3/16 3003 for aluminum car-haulers, but I fear this is probably for 3000lb race cars, and not a 4-5k trail rig...
 

·
Registered
Joined
·
62 Posts
the wide tires on said trail rig will distribute the load fairly evenly across the 14" span. my gut feeling says 3/16" will be fine. it might deflect some initially, but probably will retain its shape indefinitely after that. the highest loads are going to be when you strap it down tight and go bouncing down the road. some extra reinforcement under the areas where the tires will sit loaded wouldn't hurt.

we could model this and run some FEA on it, but knowing the actual contact pattern of the tire and the dynamic loads it will see is hard to determine. there would be quite a bit of uncertainty in the final result.
 

·
Registered
Joined
·
564 Posts
Discussion Starter #6
Thanks - I was planning on reinforcing under the tire area, so this would definately help as you mentioned... I was hoping someone with an aluminum trailer would chime in with what works / doesn't... :(

If I don't get any other input, I'll go with 3/16 6061 or 1/4 3003 - depending on what I can get for a good price... While I'd prefer the 6061 due to its resistance to bending, it seems the 3003 is WAY more prevalent and has the chance to be cheaper...
 
1 - 6 of 6 Posts
Top