BX25 Full Cage Rollbar

[NHmitch]

This is true and has been discussed here before about removing any additions of mods prior to selling. Even with a signed acknowledgement and release of liability from buyer, you could get sued by the family and likely get a stupid jury to agree to millions because you didnt explain in idiot terms that you cant pull a "Dukes of Hazzard" jump, land upside down on your tractor and live to drive off like the do in the movies. If McDonalds smart lawyers couldnt convince them that a customer should know that hot coffee is hot and deserves no compensation for getting burned with it between her legs, then I am sure any lawyer I could afford would loose big time. That is one reason I have put on an aftermarket ROPS on my Yanmar. It wasnt manufacturered with one and I wont sell it with one even though I had planned to make one myself when I bought it. Even having a store bought ROPS on your tractor and selling it to someone who then gets injured wont keep you from being sued and possible to loose the suit what with our laws and stupid jurors today and their "someone has to be at fault other than the ones involved" mentality. They're awarding millions for frivolous lawsuits and yet dont realize that some of the money they are giving away is theirs which the defendant will recoup if possible in raised fees and prices for their merchandise. Much of which we are already paying for as merchants have contingency money for lawyers and lawsuits built into their selling prices already.

HOWEVER: My point wasnt to make a point about escaping lawsuit but that lots of folks here on TBN are quiet capable of designing much better and stronger ROPS & FOPS than what they are selling on the market and to point out that just because it passed some tests, doesnt mean that it is better than a homebuilt at protecting you. I have said before, I would rather trust my design and welding on a life protection device than a $8 an hour small shop welder that 100 to 1 odds are that he hasnt tested his skills per AWS requirements and certainly not to ASME pressure piping requirements.

Gary,

I am just a big advocate for certified ROPS. The fact of the matter is ROPS have to undergo very strict testing, just like auto crumple zones. You may be able to make one that will work fine, however, I would disagree that any second year engineering student could properly design one just as effective and I only say that because the engineers who work on these specialize in this area. There are non certified ROPS on the market, and they may be put together by someone making * dollars an hour, but to be certified, you have to meet very strict standards. They spend huge money to make sure that you are safe, and meet all standards of certification, and testing, and the ROPS/FOPS are a huge safety measure that are regulated by OSHA and ISO. They test the metal at different temperatures, that can effect the strength depending on the type of metal used. If you do not believe me, look into the number of deaths that occur each year from homemade ROPS. As an engineer, you may be very qualified, but why take the chance? I was just trying to convey to people who have no experience with this specific type of engineering,that it may be a bad idea to modify your ROPS. The bigger issue is that you will decertify your existing ROPS and if you have a life insurane policy, and you die, the comapny will try to find any loophole to get out of paying. I have seen this before with modifications to vehicle safety devices. Anyways, you have very good points Gary, and this is not meant to be against you, I just worry about people getting hurt from improperly modifying, or fabricating their safety features.

The method OSHA uses to determine if your ROPS is modified is:

Certification of the machine ROPS, FOPS, or TOPS is provided to customers after extensive design and testing has been completed. This certification process is designed to ensure maximum operator protection. The process requires manufacturers to meet various standards and regulations
for the following subjects:

Any modifications to these structures such as welding, cutting or addition of attachments, can
change the metallurgy or structural strength. Such changes can reduce the effectiveness of the
structures and must be avoided.
Depending upon the specific design, some modifications or repairs may be permitted upon
authorization from the manufacturer. The original designer must assess these or a suitably
qualified mechanical or structural engineer experienced in this class of work.
Examples of changes that may adversely affect the cab certification are:
Drilled holes in the ROPS, FOPS, TOPS, seat mounting or seat
Welding on the ROPS, FOPS, TOPS, seat mounting or seat
Mounting heavy objects using existing cab bosses
Use of untested (per the standards) cab mounts
Use of attachments that exceed the machine certification weight
Use of a seat or seat belt other than listed as standard or optional for the machine
Installing monitoring screens etc, that invades the operator safe zone or interfere with
visibility
Any dents or deformation of the ROPS, FOPS, or TOPS structure
Excessive rust of the ROPS, FOPS, or TOPS structure
Heat discoloration and/or grinding on the ROPS, FOPS, or TOPS structure
Note: Failure to receive advanced approval from the manufacturer for any or all of these items
may result in voided cab certification.

 

[NHmitch]

I feel bad, I wasn't trying to hijack the thread, or argue with anyone, I just wanted to help, and I just want to make sure that you understand all of the dynamics of a modification, before making one. I have advocated for ROPS programs, and I have seen the loss that some people have experienced from accidents, so I tend to worry about modifications because they are usually never recommended. If you do, and you want to, great. Just make sure that you put lots of thought into the design.

 

[Artisan]

Don't feel bad!

I enjoy this...

My input at this second is everytime I suggest doing ANYTHING, no matter
how insignificant, a Kubota employee will recite to me a well rehersed line,
usually something like this;

"We can not approve, endorse nor help you make any modifications."

NOTHING, ZERO, ZILCH, ZIP! Ticks me off too...its my dam tractor and they act like I am committing hairycairie...

PS, Just add SOLD WHERE IS AS IS which you should do anyways when
you sell something.

 

[jim_wilson]

Just be careful, ROPS, and FOPS are very well calculated to have stress points, and if they are too rigid, or too weak, you can have catastrophic failure, and be crushed. I would try to invest in an OSHA certified ROPS or add a certified FOPS:

When the tractor above flipped backwards, this homemade ROPS tore away at the axle housing, instantly crushing the 14-year-old operator to death. The ROPS was undamaged.

This is from Iowa State University:


Iowa State University

You've read about rollover protective structures, or ROPS, for tractors. Maybe this year you'll build one for your old Farmall H.

Don't even consider making your own ROPS.

All ROPS must be crush-tested, a procedure that is extensive and destroys the structure itself. The tests determine if the protection zone around the operator station remains intact in an overturn. Without these tests, you do not know if the homemade structure will protect you during a tractor overturn. The structure gives you a false security, an attitude that may be more dangerous than an attitude that you have no safeguards.

Bars attached to the tractor axle, sun shades, or other devices cannot substitute for a dynamically-tested ROPS.

Many tractors manufactured before 1985 may be retrofitted with ROPS. Check with a local implement dealer for more information about retrofitting ROPS. The County Extension office also has a book compiled by the Marshfield Clinic that lists manufacturers, models and approximate costs.

Retrofitting can pose a difficult decision because its cost for an older tractor can exceed the machine's actual value. However, a homemade ROPS can cost you in other ways.

The building of protective structures is not rocket science. Although it often seems to be portrayed as such on the pages of TBN . Hot Rodders and car racers build protective roll cages into their automobiles ALL THE TIME. Go peruse thru the pages of any hard-core car racing magazine or stock car racing magazine and at least once a year there will be a how-to on building rollcages. There's dozens of places supplying roll cage kits for the do-it-yourselfer who wants to add a rollcage to his car.

Cars go many 10's of miles per hour faster than tractors do - so the forces involved in their crashes are much higher than a tractor rolling over.

Honestly I think a lot of the perception of the magical powers of factory installed ROPS comes from the backwoods hicks who think they can build a ROPS of FOPS out of electrical conduit and JBWeld.

Go look at some factory ROPS structures. Use the same types of tubing and wall thicknesses and so forth that are used by the factory. MAKE GOOD WELDS. Make sure you attach the structure to the tractor well. USE GRADE 8 or above bolts.

Unless you drop the tractor off a cliff - your "homebuilt" properly welded or bolted together ROPS is likely to stand up just as well as the factory one.

Yes - there are technical details that must be adhered to. No - this is not rocket science.

 

[Gary Fowler]

The only issue I see in building a copy cat version of one or making it a bit stronger is one is attaching it correctly. In the photo of the yellow International, the ROPS didnt bend or give but the guy attached it to the top of the axle where the holes were designed to hold the fenders only. If you look at the photo you see that the fenders carried forward with the ROPS because it broke the top of the axle housing off. NO failure of the ROPS frame- Just a failure of the installer to bolt around the entire axle with proper strength bolts. The entire article addresses this and does not fault the design of the ROPS only the installation.
I believe that if this had been a 4 post design with the front posts bolted into the frame, it would have held even bolted as it was, however common sense would have told him to 1) bolt around the cast iron axle rather to to the top. 2) he was not to smart to have been using a widow maker chain around the tire to try to pull up a post and (3rdstrike and your out) having his inexperienced grandson operating the tractor.
Even the best designed and installed devices cant compete against total stupidity.

 

[Gary Fowler]

One other thing,most folks here seem to missing the fact that he already has a certified ROPS system. He can install the top framing and additional posts for the box cage without welding or drilling holes in the ROPS if he desires and by doing so would only enhance the original structure. I dont think even F. Lee Bailey could defend that to the point of arguing that it nulled the original design and weakened the structure by making it a four point structure rather than a 2 point.

 

[jim_wilson]

If you are truly interested in building a ROPS from scratch - or - adding additional protective structure around your tractor I would suggest looking up the rules around building rollcage structures that most of the major race car sanctioning bodies have put into place.

There's a lot of good sense rules in there about how to build cages, the materials to use, weld quality, bracing, attachment points, etc.

Somewhere I have a copy of an old SCCA rulebook floating around and if needed I could probably transcribe some of the stuff onto a post here to give you an idea of the types of rules you should follow.

Gary Fowler made an excellent point - you could design a perfect ROPS bar - and if you do what the guy on that yellow tractor did - and attach it wrong - then it's not going to do anything for you.

That ROPS might have actually stood up to a rollover - but when the tractor went over backwards the ROPS bar just acted like a lever and popped itself right out of whatever mounting points it was bolted into.

 

[NHmitch]

I have nothing to gain from trying to stop people from making their own safety devices, and I do not surf TBN to attack these threads. I just simply cannot stand to see people die from very preventable mistakes. I am sure that I could make a seatbelt that may work from tying a piece of rope in a knot around my waist., but why take that chance?

There are plenty of implements that you can make at home, and fabricate yourself that will turn out great.. This has nothing to do with people complaining on TBN about homemade ROPS. Gary, you make good arguments and you have very good points and again, this is not an attack on what you are saying, however there have been multiple extensive research studies into the use of homemade ROPS, and all of the data strongly suggests against it. The physics of a tractor are different than that of a car, and you are not comparing apples to apples.

Again, if you want to make ROPS, or a cage for yourself, than that is completely up to your discretion, however in the case of this article, a 14 year old lost his life because someone felt very confident that they made a safe set up. http://www.cdc.gov/niosh/face/stateface/ia/03ia020.html

Again, we are all adults, and you can take what ever chances you want, but just remember that if your farm has employees, it is illegal to have a non-certified ROPS on your tractor for any employees to operate. If you make one, and some dies, you could also be found negligent. I understand that he is making a cage, and has a certified ROPS, but I have been to fatalities, and they are ugly. To me, it is just not worth taking the chance, or suggesting that some else takes that chance.

This is from the investigation into the 14 year olds death, and I think that we can all agree that that was an absolute tragedy, and I am sure that who ever built that set up, only had the best intentions.

ROPS appear simple and relatively easy to make, but they must have appropriate structural strength to absorb the energy and provide protection in the specified envelope in case of an overturn. Manufacturers design and test ROPS according to the ASAE 383.1 standard1, but it is not feasible for individuals to do so. The rollbar on this tractor appeared to be built very well by a qualified welder. The rollbar itself did not suffer significant damage in the overturn. However, the mounting of the rollbar was insufficient and the forces from the overturn broke the axle housings. It is not known if this self-made rollbar would have stayed intact if mounted according to the manufacturerç—´ specifications (see Diagram). Self-made rollbars are often thought to be better than nothing for overturn protection. However, without testing, the adequacy of a self-made rollbar is questionable. Given the complexities in design and testing, it is recommended that ROPS be built only by manufacturers who can ensure that the ASAE standard requirements are met.

Just for informational purposes and not for the sake of this discussion, if you do have employees,

The law regarding ROPS is:

A ROPS used on wheel-type tractors shall meet the test and performance requirements of 29 CFR 1928.52, 1928.53, or 1926.1002 as appropriate
These are the outlines for a ROPS test, and you have to follow the lengthy tests that are outline in IAW 29 CFR 1928.52
http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_id=13076&p_table=STANDARDS

W = Tractor weight (see 29 CFR 1928.51(a)) in lb (W' in kg);
Eis = Energy input to be absorbed during side loading in ft-lb (E'is in J [joules]);
Eis = 723 + 0.4 W (E'is = 100 + 0.12 W');
Eir = Energy input to be absorbed during rear loading in ft-lb (E'ir in J);
Eir = 0.47 W (E'ir = 0.14 W');
L = Static load, lbf [pounds force], (N) [newtons];
D = Deflection under L, in. (mm);
L-D = Static load-deflection diagram;
Lmax = Maximum observed static load;
Load Limit = Point on a continuous L-D curve where the observed static load is 0.8 Lmax on the down slope of the curve (see Figure C-5);
Eu = Strain energy absorbed by the frame in ft-lb (J); area under the L-D curve;
FER = Factor of energy ratio;
FERis = EuEis;
FERir = EuEir;
Pb = Maximum observed force in mounting connection under a static load, L lbf (N);
Pu = Ultimate force capacity of a mounting connection, lbf (N);
FSB = Design margin for a mounting connection; and
FSB = Pu/Pb

 

[NHmitch]

Artisan, and Gary, I apologize that I took so much space up in your thread, I didn't mean to hijack it. If you do the project, I hope it turns out well, I just wanted to give you something to consider. Best of luck.

 

[swick1]

Good point. I wouldn't diy rops / fops if I were commercial.