I actually used 1" square tube for the frame, and it is about an 1/8" thick wall. You could actually tip the tractor over with the cab frame I think, when you shake it the tractor shakes with it, its definitely not flimsy. The doors I used 3/4" square tube that is also about 1/8" thick wall. This sounds like it would be heavy, but two guys could remove it easily still, its not tremendously heavy. I wanna say til im done the cab alone will weigh around 200 LBs. thats without the doors since they lift off separately. The plexi pieces definitely added most of the weight.
Originally I would have loved to make this out of square aluminum, however I dont own a spool gun for my MIG welder. And after building it to the point I am at and driving it around, I think the weight of the steel helps to drown out the boiling feel of the diesel engine simply because, well steel is heavier in weight.
Im probably gonna be slow in my progress for the next week or two, I had a mishap at work that I have to heal from, but I will still be around the forum. Luckily the hard work of this project is almost over, next im on to the lights, wiper, and trim.