Hey OP, If youre a competent welder go for it using the same design as a factory folding one. There is no magic to any of this its basic fabrication, steel, weld bead and very basic engineering. Don't let all the emotional people sway you without providing some hard evidence to back up some of these wild, sky falling claims.
Dont put an employee in the tractor without re-certifying the ROPs though.
That's what I'm considering doing. My property is all flat except for some slopes on the back side of the house that are no more than 15°. I can easily fabricate a joint that will be stronger than the original tubing with some 1/4" steel plate. Besides, my BX has filled rear tires, so that lowers the CG more than normal.
While I'm not an educated, card carrying engineer, I would like to see proof that the weakest points on a BX ROPS aren't the welded areas at the mounts and the bends. The ROPS is basically a paralleogram and without a triangulating brace to opposite corners, it's going to deform at the corners, as they are the weakest points. My modification is not going to affect the strength at those points. I've seen a few rollovers, and unless it was onto a protruding object like a rock or a concrete wall, the vertical and horizontal tubes were undamaged.
I have no employees that would be operating the tractor as it is only for my personal use, so that's not an issue.
Having been around heavy equipment for a long time, I understand the risks involved, and I also know common sense is the most often missing factor in accidents.
So, I'm going to design a joint to install, and have a local shop look at it to get their opinion, and if they think it looks acceptable, this spring I'll do the installation.
I did recently see a good example of modification of an original design turning deadly. A friend sent me a video of a pilot who built and experimental aircraft, a low wing, two place composite construction bird, designed to be powered by a 100 hp Corvair flat six engine. After flying it for a while, the need for speed over came his knowledge of aircraft design, and he replaced the Corvair engine with a 200 hp Lycoming 4 cylinder engine. He was hoping to increase his cruise speed from 160 mph to around 200 mph. He also modified both wing's internal wing tanks to increase the capacity about 50%. When the video was made, he hadn't flown it yet, but was getting close to it.
My friend sent me a link last week from an article near where the pilot was based, relating that he had been killed when the aircraft came apart in flight. Now who would have seen that coming.
I also repowered my airplane, a 1960 Beechcraft Debonair. When I bought it, it had a tired IO-470 Continental, and a company in Minnesota has an STC (Supplemental Type Certificate) to install a later IO-520 or IO-550 Continental engine. The manual for doing the conversion was very comprehensive, and part of the conversion included installing some doublers in the area of the engine mounts the handle the additional stress for going from 225 hp to 285 hp. I worked under the close supervision of a local A&I (An A&P with an inspection authorization) and did all the work myself. When I was finished he signed off on it and said I had done and excellent job. The plane is a completely different animal now, and performs the same as a later model that was built with the IO-520, while burning the same amount of fuel as the old tired 470.
The company the I purchased the engine and installation kit from spent years generating piles of paperwork and doing hundreds of hours of light testing to satisfy the FAA engineers, even though Beechcraft installed the same engines in later models that were nearly identical in structure to my plane.
So I appreciate all the comments and opinions and have read and considered all of them in my decision.
Good gosh, this request for some information has take on the dimensions of a political debate. Never would have guessed it.
Keep the orange side up!