The 24 Hours of Lemons Forums → Lemons Newcomers → Roll cage resources
hello, my university is having us do a Lemons car for our senior design team (capstone project i know how cool is this ) i am so excited to be a part of Lemons. they are making us make every part of our car including the roll cage.
we have a 1994 BMW 325i sedan we are going to race with.
we are looking for any design references for Lemons rated roll cage for that car.
thank you very much!
Have you looked at the 'How not to fail tech' handbook here:
https://24hoursoflemons.com/wp-content/ … 040419.pdf
You won't find a specific guide to your particular car on here, but there are a few known companies that can sell you a pre-bent kit. Roll Cage Components seems to come up in these forums fairly regularly, but I have never built a cage myself.
Otherwise, you will need to get a real pipe bender and probably some software to plan out your bends.
A couple of basics. Yes, study the how not to fail tech. Also look in the rules where it specifies things like spreader plate requirements and material (i.e. DOM or ERW). But really, your best resource is to directly contact the head of tech pagel@24hoursoflemons.com . who is a mechanical engineer that can speak your language.
Where are you located 313? There might be teams in your area with similar cars that would be willing to let you take a look at their crapcan that has already passed tech... Do you have experienced welders in your class/group? If you are going to tackle a cage that is one thing you will need for sure.
Where are you located 313? There might be teams in your area with similar cars that would be willing to let you take a look at their crapcan that has already passed tech... Do you have experienced welders in your class/group? If you are going to tackle a cage that is one thing you will need for sure.
we do have experienced welders and professional engineers overseeing our project my family's team is in the Detroit area but we are located in golden colorado. I just got done doing the Gingerman race and had a blast. my family team did not install the roll cage themselves. i am looking for general measurements so i can start on the drawings and FEA of the roll cage.
The purpose of the project may be for your team to do the work yourselves.
BTW: Read the forum topics - especially about cages and seats.
I know a guy who uses stiff wire for his measurements.
But he's also really good at mental 3D spatial relationships, so he always knows which surface of the tubing the wire represents. Amazing to watch.
I believe the tubing suppliers (also, S&W race cars here in PA) have guidebooks for submitting measurements.
If you're looking for info on how to go about designing and building a cage, I watched this series a number of times before I built my first cage. It is a long series, but he does a really good job explaining how to measure for and then mark and bend a cage. Like I said, watched it like 3 times, made notes, then bent our main hoop perfectly the first time. We only screwed up 1 bar, and it was the first forward down bar. Everything else after that we got on the first take. That wasn't natural skill, it was the hours and hours and hours of prep I did first to make sure I understood how to measure correctly, and how to translate that into bent bars.
https://www.youtube.com/watch?v=uqY6KITUnXU
General tip, remove the engineering from the cage building. Go do FEA and drawings and reports if it's required for your capstone, but ignore it when you build the actual cage. Fitting a good cage comes down to how well you can measure and then execute the bends and notches. Unless you're lucky enough to have a real 3d scanner and a full suit of CNC bending and notching tools, the quality of the fit and finish of the cage is 100% on your ability to hand finish the bars. Your drawings may end up being not representative of the final cage if you happen to measure some angles just slightly off. The end goal should be a quality cage that fits the car as best it can, not a cage that perfectly matches your first drawings but poorly fits the car.
+1 for The Fabricator Series guy
I think he's great with the video instruction format, and I think I picked up that link here in the forums, also.
I have the bend profiles for an e36 coupe, if you needed them
The 24 Hours of Lemons Forums → Lemons Newcomers → Roll cage resources