Originally Posted by chadcooper55
I don think they make 1 3/4 sch 40. 1 1/4 sch 40 is close to 1 3/4 .120. If he is using a106b or something similar what is the downfall?
because the chassis itself is the most difficult thing to modify once it is built. you can change and upgrade almost every component like steering, seats, winches, cooling, powertrain, etc. But the chassis is done once it is welded. It's not the place to save coin.
1 1/4" sq40 is 1.66 OD and .140 wall. As far as A106B or greater... judging by the seams, it looks like A-53 which is available at about any diameter. You have to be extrememly carefull where you put the seam in the bender. The seam portion can not change size dimensionally (can't be on the ID or OD) or it will split.
Most pipe is more brittle then a HREW and really not even comparable to a DOM. In a rig that you plan on bouncing off trees and rolling, I don't see why you would take the risk of a brittle failure and having to re-do the chassis down the road. I guess I don't know about SRRS safety rules, but there is a reason (or 3 or 4) that every motorsports sanctioning body that has any sort of good reputation requires DOM and HREW, depending on the location of the tube and weight of the chassis. So the chassis won't be comp legal in a lot of venues (I'm sure you can paint it black and hope they don't notice), but the OD of the pipe might stick out to anyone that techs in a lot of rigs...
It's just a weird spot to save money. Thats all. Carry on.