Building a ROPS?!

[Slamfire]

My Mitsubishi D 1800 has a couple of flat pads with bolt holes on the rear axle also, they are for mounting the fenders, in either one of two positions. I wouldn't dream of attempting to attach a ROPS to them. The installations I've examined in junk yards had heavy plates, bolted through all four corners, with additional attachments to the frame of the tractor. I rolled my tractor once, the exhaust stack prevented it from going onto the top. I just installed dual wheels to prevent that, and am still quite leary of side hillin'. I don't know what else I can do as Mitsubishi doesn't have any aftermarket ROPS available for my model. I've only the use of one eye so weldin' my own is out of the question, and all the local welders have turned me down. Let me know how you decide. /forums/images/graemlins/confused.gif

 

[EddieWalker]

kanmac,

Obviously you make some good points. If I implied that there
has only been one instance of an injury from a home made ROPS, then that was wrong of me and I apologize. I'm sure there's dozens and dozens of times this has happened.

This is a discusson on theory and opinions based on the original post of weather it would be better to build a ROPS, to modify a factory one to fit, or not have one at all.

If you can find a factory one, then I agree that would be the best avenue. No question about it. But your position that not haveing one at all is somehow safer contradicts the events that happened in your link. That accident was destined to happen with or without ROPS. Would they have done all those things they were doing if they didn't have the ROPS? My guess is yes.

There's no need to get upset with me because I disagree with you. It's nothing personal on my part. If something doesnt' exist, then create it. That's just me. You have a different way of doing things and that's wonderful too. Just not my aproach in life.

Sorry your through with the discussion, I've enjoyed reading yours and everyone elses views on the topic. All my tractors have factory ROPS and it's something I don't ever expect I'll need to worry about for myself.

But to be able to discuss a topic with such oposing and various views is fun for me along with educational.

Thank you,
Eddie

PS, what would you do if you had an old tractor without any ROPS and couldn't find a factory unit for it?

 

[cleatus]

I've enjoyed this discussion and I knew that there is no way we'll all agree on this subject,as even the gov's cain't. THe reason they got involved at all was to slow down law suits that were putting bussiness into bankruptcy that were supporting their campaigns. I know that there was also the thought about some saffety for the consumer, but more than anything money was involved, for reelection bids and manufacters and hopfuly less bankrupties,as that also cost companys money.
The one thing I do fill strongly about is I'm safer on my none ROPS row crop 55yr old tractor with piss poor brakes than I am driving to the store, which is only 2 1/2 miles.
I know each of us feel different about saffety and each of us will normaly try to be safe with the chores we do. I also know that most people feel very unsafe holding raw edged none safety glass and this is something I do most every day, without the use of gloves, but as this has been my job for years I know what I can handle.

 

[bobodu]

</font><font color="blue" class="small">( kanmac,



PS, what would you do if you had an old tractor without any ROPS and couldn't find a factory unit for it?



)</font>

You simply don't put yourself in a situation where an accident is LIKELY to occur.I saw a program on one of the learning channels about how accidents happen.Almost always,more than ONE thing has to go wrong...ie: brakes fail,poor maintenance,following too closely and excess speed.
If I read the single article cited correctly,the kid would still be alive IF..
The tractor wasn't pointed uphill
or..
He was doing something stupid like wrapping the tire.
or...
The darned post wasn't so firmly set..
or..
The bolts were longer.
or...
He was a little more experienced and wouldn't have tried this stunt.
My point is....I don't fly kites in a lightning storm nor do I clean a loaded gun.

 

[toy]

I have been reading this thread , but I never read the attachment of the tractor accident until tonight. According to what I read it wasn't the rops that failed it was the mounting points of the rops that failed . That was a sad thing that happened and Im sure the dad and the grandad will always be saying what if I had done it this way or that way, but what we need to consider and get from this topic is that when we add something to the tractor to carefully study all aspects of the job before we do this. This is one of a many tractor rollovers that had tragic end but I figure that there have been many that have happened where no harm was done where homemade rops have held up and saved lives . This thread has given me something to think about [it's a learning experience] take your time and consider all aspects of what your going to do ahead of time research the how toos of what your doing. One says you can build your own rops the other says not to its not safe, what I learned from this you can build your own rops its doable but be very carful and if you feel the least bit intimidated about building or question your ability of doing so leave it alone and get someone that knows what they are doing to do it for you whether it is a factory rops or a home built one.

 

[JustGary]

I looked carefully at my Kubota L2800 yesterday evening. The ROPS attaches only to the rear axle, in a fashion very similar to that in the accident report. Does that mean my tractor is not safe? Yup. I can only hope that I never get the opportunity to field test its ROPS. Well that's not exactly true; I can try really hard to not test it. That beats hope every time.

Show me any ROPS you can dream up and I'll show you a situation where it could fail. Granted, my failure mode might not be a "roll over," but that giant log shouldn't crush you when it falls on you, should it? Every engineer works within design constraints, even if they are back yard engineers. Had anyone asked me about the one in the report, I probably would have declared it safe for any rollover. Would that make the death my fault? I don't think so. What we don't know about the accident is how much power the boy applied to cause the rollover. The bar might have supported a simple rollback, but perhaps the boy popped the clutch at full throttle. We don't know.

If that tractor had had a hydro transmission, the boy would probably still be alive. Does that mean we need to ban gear transmissions? Of course not. Forget the transmission, tractors aren't safe... should we ban THEM?

I would not hesitate to build my own ROPS for a tractor that didn't have one available. Would it be bullet-proof? Probably not, but it would sure beat what's on the tractor now. If I sold the tractor and was worried about the ROPS, I would remove the it and sell it to the guy separately and make him put it on. I would call it a "canopy support" too.

Regards,

Just Gary

 

[toy]

Like I said it wasn't the rops that failed it was the mounting points that failed as evedenced by the pictures. I asume that at some point there had been a rops on it previously but had been taken off, when it was taken off was something else also altered on the machine and I beleive there was something about shorter bolts that was used than what was supposed to be used and or maybe the wrong grade bolt. In an ideal world they could have found a machine like that and checked out their rops and checked other rops on other machines to see how they were mounted. I think someone in this thread mentioned mounting the rops to the frame on their machine that sounds like the safest and best way to mount a rops if it was possible. I know that those folks are heartsick over their loss. Its good to be reminded to be cautious when you are working, but not so much that you become paralized by caution and cannot do anything.

 

[keeney]

One point I think is pretty clear here is that designing safety equipment is typically a one-shot deal. Most people cannot afford to to test their tractors to destruction or failure, so the only valid design strategy is to try and anticipate the worst cases and over-build it.

All of us who have read this thread would certainly take back-flip protection into consideration if we designed our own ROPs. What would we still be missing?

What about seatbelts? Anybody ever design one of those before? They are as important as the ROPs in this protection strategy. What size webbing? What to anchor it to? What angle to the seat? What about the seat itself?

Lots of design decisions that would take a lot of thought to get it right. In addition to careful thought and consideration, a lot of these things are decided through corporate experience, testing, and unfortunately, learning from previous failed designs.

In order of safety:

1. Buy a tratcor with a full 4-post, commercially available FOPS / ROPS or cab and seatbelt.

2. Buy a tractor with a 2-point ROPS roll bar and seatbelt.

3. Buy a factory-designed add-on ROPS for a tractor without a ROPS.

4. Carefully fabricate a self-designed ROPS for a tractor without a ROPS

5. Poor ROPS design that only protects in 50% of cases.

6. No ROPS

- Rick

 

[drmiller100]

Again, I'll submit involve a local person with experience in helping you design it.
Drag racers really do have good practical knowledge in building roll over protection. There are tried and known materials.
A simple roll bar has 4 mounting points. 4 mounting points means the structure will be tension/compresssion, not bending. Take a straw, and try to bend it. Pretty easy. Now take that straw and try to pull it apart. Much much harder.

 

[Paddy]

Your point is good. Have someone design it who has exp.

In addition; I'm a test engineer in the ele field. First, all designs that will be produced in high numbers will be made of the lowest cost method! Passing the ANSI, American National Standards Istitute, test; who said it passed on the first time! And if you think the item you just bought represents...exactly what was tested, your kidding your self. In fact test don't always represent field duty, how could they with all the options for problems. Tests are descibed in 3 types, Design tests, Conformance tests and Routine tests.

I have seen products retested, SAME DESIGN, 3 times to pass. Most likely the products going out the door look like the ones that did not pass.

In summary, it is tough to match a factory design with such thin guage materials and pass the same tests. So if you want to build a ROPs, don't copy one, exceed what you see!

patrick