In a thread a few months ago someone (I wish I remembered who) mentioned that they put together all or part of their robot frame with connectors from this company:
http://www.estoconnectors.com/
McMaster sells similar parts, but for 3-4 times the price. My new team is working on a simple offseason bot and I'm looking into trying this for the superstructure. The tubing is similar to VexPro's VersaFrame however doesn't have brackets that interfere with bumpers and things.
If the friction fit isn't enough to withstand a beating then my thought is to drill through the tube and the fitting and put a #10 fastener through for some extra strength.
My question is: Has anyone ever used this or a similar system and how well did that work? Also, would you advise even trying this in the offseason?
Our team calls me "John Regular Neun," because John V-Neun is so spectacular! - John Neun [more] 
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