COUNTRYCOWBOYRANGER
New member
Would 2x3x.120 wall rectangular tubing be heavy enough for frame rails or would 2x3x.188 be a better solution? Thanks!
Strength to weight ratio
- Thread starter COUNTRYCOWBOYRANGER
- Start date
mikeprince
Member
The M101A1 which is designed to carry 3/4 of a ton offroad for the military uses 3" x 1.5" x .120 u-channel (not rectangular tube).
I believe many of the expo trailer builds are significantly over built, which translates into a bunch of adverse effects: harder to pull through rough terrain, bad gas mileage, harder to panic stop in emergencies, more wear and tear on tow vehicle, harder to hitch up and un-hook by hand, etc.
I'm in the process of lightening up an M101A1 for overlanding, and beside keeping the frame largely as-is, will rebuild the trailer tub and drop in a 3500 lb axle for most of the weight savings. As the build progresses I'll post info about the exact weight savings.
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Hillbilly Heaven
Explorer
2x3x0.083 would be my choice and I think it is on the heavy side.
Hummelator
Adventurer
I built my 5'x9' out of 2"x3"x.125.
Would almost say it's overkill actually.
If I were to build again ( from steel) I would go 2x3x.100 c channel- still overkill but would ensure no damage from over stressing it.
I would like to lighten the weight of my trailer so in the next year or two I plan on building a bolt together aluminum trailer.
Would almost say it's overkill actually.
If I were to build again ( from steel) I would go 2x3x.100 c channel- still overkill but would ensure no damage from over stressing it.
I would like to lighten the weight of my trailer so in the next year or two I plan on building a bolt together aluminum trailer.
ottsville
Observer
First question anybody should ask is what size trailer and how much weight you will be hauling. But in general, 2x3x0.120 is overkill for what most people here are doing.
Go take a look at an RV trailer. You may be surprised at how they are made.
Just remember dropping down in wall thickness will save weight but its pretty minimal. For example 3x2x1/8 wall weighs 3.9 lbs a foot, 3x2x.08 wall weighs 2.72 lbs a foot which would save you only 30-40 pounds depending your design. But the thinner wall you have to be more careful welding, versus the thicker wall.
DaveInDenver
Middle Income Semi-Redneck
Kind of an open ended question. I'm not a mechanical engineer but it seems to me you need to know length, tube geometry (I'd use a rectangle) and expected load. Then you may need to decide how much deflection you can tolerate. You can look it up, there's online calculators for beam deflection. If I had to guess even 11 ga (0.120" wall) rectangular tube will be more than sufficient for a trailer frame.
COUNTRYCOWBOYRANGER
New member
Basically I'll be making a M416 Style of trailer.
villageidiot327
Explorer
The trailer I’m modifying has a .1875” 3” angle iron frame. The tongue is .250” 3” c channel, and the upper portion was 2” .125” angle iron.
I’ve mowed all that down and will be building off the base frame with 2” .120” wall box tubing as the uprights, and then a 1x3” 13ga too rail. It will have a tub inside skinned of 16ga on the sides and 14ga on the front and floor. Not sure what the tailgate will be, likely 1x3” 13ga with a 14ga skin.
The lid will be aluminum.
I’ve mowed all that down and will be building off the base frame with 2” .120” wall box tubing as the uprights, and then a 1x3” 13ga too rail. It will have a tub inside skinned of 16ga on the sides and 14ga on the front and floor. Not sure what the tailgate will be, likely 1x3” 13ga with a 14ga skin.
The lid will be aluminum.