Building a ROPS?!

[mark777]

For me, here it is in a nut-shell.

A certified ROP's rated for your make and model is "legally" better. Even the residual value of your tractor will be higher than that of one without the same structure. Most manufacturing companies meet all the minimum standards, but still keep costs down to maintain a higher profit margin.

And (as Eddie stated) a competent weldor with the correct materials can build one as good, or better. Diagonal supports, gussets and higher grade hardware is a good example to a superior hand built structure.

This is the catch and it's a real "Catch 22":

If you build and install a ROPs and seat belt for yourself that's OK....even legal. If you sell that tractor, or build a ROP's for any other tractor then you are liable for any injury sustained, regardless if it's the operators error or not.

If you build a ROP's but call it something else, like a HD canopy support and include seatbelts, your liable for the same circumstances as above.

And finally, doing the same as above and not including seat belts is as, or more dangerous than a tractor with no structure at all. I hope this helps in understanding why I do not manufacture my own (IMHO well built) ROP's.

Mark

 

[OldMcDonald]

What kind of seat belts do you have on your tractors, lap, diagonal as in cars, full harness? I have never heard of seat belts on ag tractors until this thread. Old McDonald.

 

[drmiller100]

u guys are funny.

a tractor flips, and what are the odds you will end up still sitting in the seat when it is all done???? so you all wear seat belts????

any rops is better then no rops at all.

Roll bars for race cars have some GOOD information. If you built a roll bar to specs for a 12 second quarter mile car, you'd probably be pretty safe in your 2 mph tipover. In particular, use good materials. Square tubing is a joke. If you are doing it yourself, either use a LOT of THICK steel, or mandrel bent roll bar tubing.
Further, use good mounting points. A roll bar that attaches in two places is worthless. Have a roll bar that attaches in at least 4 positions, each at least 3 feet apart. the earlier post is a great example. If that bar had just two forward supports, the kid might have lived.

The quarter mile fab shops are pretty friendly folks, and they have a LOT of experience, and they are usually REALLY friendly about helping people design good quality roll protection at very reasonable prices. And they have a LOT of experience in thinking about roll over protection.

Just my thoughts.

 

[markct]

drmiller100, i agree with you entirely that any rops is better than no rops. my dozer has a canopy type structure that i made primarily to be safe from falling tree limbs and such, while it dont consider it a rops by any means, if i ever were so unfourtanate to have a rollover its very likely that it would keep the machine from goin all the way over, it would probably stop it on its side, a much more likely place to be able to survive. another case in point is that i know of a guy that had a ford 8000 ag tractor, very simular to the one i have, it had a non rops cab on it, it was not a strong cab by anymeans, just formed sheetmetal mostly. he had a rollover, the tractor stopped on its side rather than going all the way over, probably saved his life, im not saying i would trust that type cab to be a rops by any means, but it was enough to stop it, thats better than nothing at all!!! my ford 8000 has the same style cab and i plan to build a rops for it eventualy, i have no worrys at all about building it. me and my father are the only ones who run it, and i am a competent welder so i see no reason not to build one. can hurt

 

[mark777]

Just a lap belt. The type you see on any late model tractor, with Torx bolts and welded nut plates for anchor points.

 

[kenmac]

Jerry , if you look at my 1st post on this thread I have a linc to the accident you refer to.

I talked to one of the yanmar dealers that had alot to do with getting ROPS developed for yanmars. He said that they don't roll a tractor to test the ROPS ,that they use hydraulics in the test process. I purchased one of the 1 st. ROPS for a yanmar & I have to say ,it is a better design than I could have made in my shop. In the test process they were able to know where to install the thickest steel & critical bracing. Without the testing the adverage person just don't know. You say ,any ROPS is better than none. Not correct , the man in the linc I provided must have thought the same. It may give you a false sense of security that I have a ROPS now so I want worry so you get into a situation & your ROPS fail, but like I said before, it's your life !

 

[EddieWalker]

</font><font color="blue" class="small">( You say ,any ROPS is better than none. Not correct , the man in the linc I provided must have thought the same. It may give you a false sense of security that I have a ROPS now so I want worry so you get into a situation & your ROPS fail, but like I said before, it's your life ! )</font>

Kenmac,

You say that the guy "must have thought the same." You are basing your position that no ROPS is better than a home built one base on what you "think" one guy in one accident might have thought.

Others have pointed out first hand experiences with rolls and how their ROPS performed. Can you state a single instance where a person was in a roll on a tractore with no ROPS that they came out of it without injury?

To me, this is an important distinction.

Eddie

 

[MarlandS]

Not to start a fight, but the story in that link shows how everything that can be done to create an accident was done and the kid payed the ultimate price and Dad and Grandpa will forever live with the guilt

First, a certified welder should have known about welding to cast and it's limitations. I get the impression that they installed the ROPS for fit and then neglected to finish it with longer bolts and a plate on the bottom (wasn't the original lower plate there already?) It would have probably been adequate for tipping the way it was set up but not flipping, especially anchored and under power.

THEN, they had a barely experienced operator doing one of THE most dangerous things you can do with a tractor, chain ,and post. Wrapping the wheel to pull posts isn't called the widow maker for nothing, I've been operating tractors for 35 years and never would consider doing this. It's too easy to miss the clutch or for your foot to slip off.

A ROPS is an easy thing to build correctly, it's not too tough to make it safe for rolling the tractor clear over but you CANNOT stack the deck totally against yourself and expect ANY man-made structure to keep you alive.

 

[keeney]

In regards to:

"To imagine that a factory ROPS found on any modern CUT will protect you in anthing but a basic sideways roll over or lay-down isn't realistic."

Well, its best not to find out the hard way, but all OSHA certified ROPS must also supposedly provide back-flip protection.

The commercial manufacturers do spend a fair amount of effort optimising their designs to be the most cost efficient way to manufacture a structure that will still meet the minimum requirements. One optimization is to only attach at two points. Its not easy to make it reliably strong enough attached only at the rear axle, so its not something I would recommend somebody try on their "1st generation, rookie, ROPS design". Also, I would not recommend blindly copying a commercial design - it would be easy to overlook something like the strategic use of a high strength alloy or the significance of a few 1/8ths of an inch of extra thickness in a key location in a casting. It is also likely that attempting a stright copy, you will be unable to sufficiently duplicate something like some cast-in additional reinforcing in the axle or a strenght-maintaing bend with little or no collapse in square tubing.

There are lots of ways to design a structure with a lot less risk of failure and a lot less chance of having a small ommission or defect turn into a failure. Its called a robust design strategy. Some people call it overbuilding. On example is attaching the ROPs at four points to the tractor. Its a lot less challenging of a design. The stresses are much lower overall - the attachment points are all in simple compression or tension, not bending. There is some redundancy by having four points vs. two. Less precise positioning is required because the protected volume is larger. The four-post design also adds some protection from stuff being dumped back on the operator from the FEL.

As another poster pointed out, don't forget the seatbelt. Its a very important part of the design.

- Rick

 

[kenmac]

Eddie, this is only one instance . DO you think this is the only accident out there where someone has fabed. their own ROPS and it didn't hold & someone was seriously injured or killed ? If you think so then you are badly mistaken.This is the only one that I happen to find & post do a google search on this subject ,I'am sure you will find many more. Eddie , if you want to build you something out of sheet metal & glue it togher with super glue & call it a ROPS it's ok with me . Just don't put someone elses life at risk because you think build a better ROPS than one that has been tested & certified. Yes look on the yanmar forum ,there is sa post there where someone rolled their tractor with no ROPS without getting injured. All it takes is a little searching & you too can find these things . As far as I'am concerned , I'am through with this subject.