Humvee Cage Build
Hey folks, I'm designing a cage for my 4 man Humvee in Bend-Tech and ran into a problem. My first version I was happy with was just under 300 lbs! I'm thinking that kind of weight in the cage may make me roll:). So I went from cool design to cutting weight. I had originally planned to use 2" .120 wall DOM for everything but I can't get under 270ish doing that so I've been looking at changing some tubes to 1.75 and 1.5 .120 wall DOM. My question to all you with experience in building cages for large off road rigs is, how heavy is too heavy?
We like to look to the true experts on this, like SCORE for offroad and the SFI for drag racing, etc. SCORE requires 1.75 x .120 on vehicles under 4400 lbs and 2" x .120 on vehicles over 4400#. This is for racing of course, but safety is the last place I scrutinize weight. 300 lbs doesn't honestly sound that heavy for an offroad cage in a Humvee.
We have weights per foot here: https://woocommerce-151096-2596814.cloudwaysapps.com/tube-calculator/ and 2x.120 is 2.42 lbs per foot. So you are using 123 feet of tubing, which is 6 sticks. I think that 4-5 is a more common number of sticks, but a Humvee is over a foot wider than a usual vehicle, so I still feel that this is reasonable.
Remember that triangles are stronger than squares (in cage design)!
Thanks Joe. Just finished the cage design I'm going to move forward with. Have to figure out what I'm doing wrong with the bender first though.
Just did my first bends today to get the calibration done and ran into issues. I had read that using the roller pressure die could cause issues when bending 2" .120 wall DOM but that it may work. I gave it a shot and bent a pin, which I had read could happen with the roller. Also had issues with the clamp slipping and the ram really seemed to be struggling. So I got the pin out and tried using the normal pressure die. Cleaned up another 3 ft tube and gave it another shot. I have two clamps so I used my other new one, lubed the dies and the pipe to see if that would help the ram. Clamp slipped again and the ram still seemed to struggle but this time I was able to get it bent to 90 so I could check the spring back. Been dealing with a snow storm all day too so dealing with the ram is a tomorrow thing.
Was going to attach a screen shot of the Bend-Tech image but having issues attaching files, not sure why yet.
Here are a few screenshots of the Bend-Tech design and of the big POS get'n all this love. Using a mix of tube to try to keep the weight down. The red is 2" .120 wall and the blue is 1.75 .120. Estimated weight is 278.
She had a tough wheel'n season. More pics of her abuse are on my instagram @mattyd_603