I have seen many arguements over dom vs. hrew vs pipe for rollbar/cage material. What are the pros and cons of using stainless tubing? I have a relative who owns a weld shop and would like to build a rollbar/cage out of stainless for me, but if it is not recommended, I'd just assume pass up the free offer. I will not be hardcore offroading, but a roll is still a roll.

Thanks for any information.

Stainless steel is made for one purpose...to resist rusting. It is weaker than any other type of steel. Period.

The less iron and carbon you put into steel, the weaker it is. Stainless is for kitchen forks and exhaust systems, not rollbars.

stainless will rip and crack apart. Don't waist your time or money building anything like a roll cage out of stainless. I've seen some bumpers before and they looked cool, but that's all I'd use it for on my truck.

Thanks for the feedback. I'll go with other tubing, and if there is anything I have learned from Pirate, I'll triangulate heavily.

John

Stainless steel is made for one purpose...to resist rusting. It is weaker weak=fragilethan any other type of steel. That's not correct: Stainless steel has a great hardness, stability and toughness than normal steel, may be to much hardness, cuz it defoms less than normal steel but it is stronger Period.

The less iron ???and carbon you put into steel, the weaker it is. only less carbon (weak=elastic) Stainless is for kitchen forks and exhaust systems, not rollbars.I don't think so

stainless steel 15 % Cr, Mo and V. Carbon is 0,45 % !!! Rest is iron and additives S, AS etc. Disadvantage of stainless steel is weight, special welding and less deformation. But until stainless steel is breaking, there have to be a lot of force to do that. I prefer stainless steel than scrap metal.

I have made my rollbar with stainless steel, and I will expand building it all around the body. :D

http://www.xjusa.com/projects/xjtomj/images/P101000v.jpg

http://www.xjusa.com/projects/xjtomj/images/P101000v.jpg

Can't you bend stainless???

Not 30" and with this little radius. Okay normal steel is better bending. :D

stainless steel 15 % Cr, Mo and V. Carbon is 0,45 % !!! Rest is iron and additives S, AS etc. Disadvantage of stainless steel is weight, special welding and less deformation. But until stainless steel is breaking, there have to be a lot of force to do that. I prefer stainless steel than scrap metal.


You are wrong. Stainless is weaker in almost every way than high carbon steel.

Let's make this basic...if stainless was stronger than high carbon, AND prevented rust, then why would high carbon even exist?

Stainless stretches more than carbon steel. It's more brittle to sheer than carbon steel. It's harder to machine, bend and weld than carbon steel.

A stainless bolt will break much sooner than a carbon bolt of the same size, both in sheer and in tension.

Finally, you cannot use a magnetic 90/45 form with stainless tubing.

You are wrong. Stainless is weaker in almost every way than high carbon steel.

Let's make this basic...if stainless was stronger than high carbon, AND prevented rust, then why would high carbon even exist?

Stainless stretches more than carbon steel. It's more brittle to sheer than carbon steel. It's harder to machine, bend and weld than carbon steel.

A stainless bolt will break much sooner than a carbon bolt of the same size, both in sheer and in tension.

Finally, you cannot use a magnetic 90/45 form with stainless tubing.

Making blanket statements like you have about a subject matter you apparently have little knowledge about, while it is the Pirate way it does no one any good.

Unfortunately Paz you are wrong in many aspects of what you wrote above as all of the properties ascribed could be attributed to high carbon steels as well. Without a material grade description and heat treatment condition for both materials being compared it is a vague, fill in the blanks generic rant.

There are many more modes of corrosion than rust, various SS grades are more resistant to some of them than CS but fare worse in respect to CS in others.

With the many grades of steel available one has to look at the intended use and the economics of the situation and base your choice on that.

Not all grades of SS are non magnetic and even cold worked 300 series SS can be considered magnetic.

Making blanket statements like you have about a subject matter you apparently have little knowledge about, while it is the Pirate way it does no one any good.

Unfortunately Paz you are wrong in many aspects of what you wrote above as all of the properties ascribed could be attributed to high carbon steels as well. Without a material grade description and heat treatment condition for both materials being compared it is a vague, fill in the blanks generic rant.

There are many more modes of corrosion than rust, various SS grades are more resistant to some of them than CS but fare worse in respect to CS in others.

With the many grades of steel available one has to look at the intended use and the economics of the situation and base your choice on that.

Not all grades of SS are non magnetic and even cold worked 300 series SS can be considered magnetic.
My knowledge of stainless vs carbon steel is from using it in real life engineering stuff. I consider DOM vs HREW vs stainless tubing to be based on the most basic rules...we're not dealing with exotic alloys and heat/cryo treatments.

Now, will you disagree that HREW is stronger than stainless tube for cages?
Will you disagree that HREW is easier to work that stainless for cages?
Will you disagree that stainless is a very poor choice for cages?

If not, why did you feel the need to post?

if stainless is weaker why does it take 3 sawzall blades to cut a keg in half?









fighting on Pirate is like the Special Olympics... no matter who wins your still retarded

My knowledge of stainless vs carbon steel is from using it in real life engineering stuff. I consider DOM vs HREW vs stainless tubing to be based on the most basic rules...we're not dealing with exotic alloys and heat/cryo treatments.

Now, will you disagree that HREW is stronger than stainless tube for cages?
Will you disagree that HREW is easier to work that stainless for cages?
Will you disagree that stainless is a very poor choice for cages?

If not, why did you feel the need to post?

I will repeat for you, without a material grade description and heat treatment condition for both materials being compared it is a vague, fill in the blanks generic rant. Which means that the statements you want me to agree or disagree with could be true for either materiel in comparison with the other.

If you have so much knowledge about the subject at hand where did the non magnetic comment come from?

As well when you state "high carbon" to describe carbon based steel you should really know what you are describing.

Until you can come up with a valid position backed by facts and knowledge, rather than the weak, easily picked apart rants you have posted the only thing you are doing is wasting everyone's time including yours.

Stainless is a much harder steel than normal steel. They even make special drill bits for drilling stainless as it will eat normal drill bits.

OK, since you want to discuss minutia rather than help answer the original question.

Let's assume he's talking about 304 stainless.
Let's assume we're talking about 1020 carbon steel.
Both are standard tubing, no exotic cryo treatment or anything like that.
Data taken from www.azom.com...

The stainless:
0.08% carbon
205 MPa yeild, 515 MPa tensile strength
215 HB hardness
40% elongation

The carbon steel:
0.2% carbon
295 MPa yield, 395 MPa tensile strength
111 HB hardness
36% elongation

So, Hmmm...
The carbon steel has over twice the carbon in the matrix (even you in a post several years ago said that carbon content is a strong indicator of steel strength). It has a much higher yield strength, and a lower tensile strength. Elongation is similar, but the hardness is half of that for stainless.

So, let's hit this steel with a rock. It will resist yielding better than the stainless. It will scratch quicker, but it'll stand up to a harder hit with no deformation. If the hit is REALLY hard, it will bend sooner than the stainless, but isn't that part of a cage? Bending of the steel will absord the impact, and not transmit it to other pieces. The welds will be happier.


Finally, let's discuss the future of this cage. He won't be able to fix it on the fly when in the field. Welding gussets to support damaged areas won't work (assuming someone around has a plain jane mig welding to do the work). Trying to toss some HREW in to fix areas won't really work. Heck, even welding the actual stainless cage to the carbon steel frame will be a bitch.

So, as far as I'm concerned, a stainless cage is not good compared to a carbon steel cage, in almost every area. Why the arguement??

You are doing better Paz, that is almost the exact argument I wanted to see. A real world comparison between two common material grades that lends credibility to your position which is something not achieved with a "its bad" rant. If that had been your first response I would have likely not responded or responded with a X2.

Due to the wide variety of material grades available in the mild carbon and stainless material groups you need to "discuss minutia" in order to have a tenable discussion as 0.10% carbon content difference or a heat treatment can have a large difference on the materials properties.

Carbon content is a good indicator of UTS in mild carbon steel but if you have a high enough carbon content that it is hardenable or alloying elements it becomes a blurry indicator.

Paz, you seemed to have misunderstood the yield strength and tensile strength. The yield strength is how much pressure a material will withstand before the pressure causes a permanent deformation of 0.2%. So given the material data provided, The stainless steel will start to deform before the carbon steel, ALWAYS!!!!!!! It doesn't matter "If the hit is REALLY hard" because if the smaller impact cause a deformation so will the larger one.

Now given the tensile strength of the materials the stainless steel is FAR stronger than the carbon steel. the carbon steel will break long before the stainless steel. So given your situation of a roll cage , the stainless will deform sooner and absorb more impact and transfer less impact to other parts of the structure, and it will actually take more force to rip it apart.

So as far as strength of materials goes in this case with these particular alloys, the stainless steel is actually a better material when it comes to absorbing an impact.

HOWEVER!!! yes it is twice the cost of DOM, HREW and chromoly, and it cannot be easily fixed in the field, you need a TIG or stick to weld it and you don't want to weld it to the frame of your vehicle as it will cause galvanic corrosion and the frame will rust out from around the weld. Not to mention the rods are expensive to weld steel to stainless. Also any stainless part needs to be insulated from the mild steel parts as it will also cause galvanic corrosion.

also note that higher the carbon content the HARDER the steel is, and generally the more brittle it is and likely to snap or crack rather than bend when it reaches its yield point. ie Your axles are made from ultra high carbon steel (1-2%), how many bent axles have you seen? and how many snapped ones? The stainless steel is more ductile and will deform sooner and take more pressure before ultimately failing

of course you can use MIG, but I prefer the look of TIG and stick.

5 year old thread bump? Paz has not posted here in over a year.

5 year old thread bump? Paz has not posted here in over a year.

ya, but when he's trying to appear to be the smartest guy in the room........ :rolleyes:

i know this thread is old, but i found it in a google search for stainless cages.
i'd like to get an answer from someone familiar with metal properties, not just an opinion on kitchenware. :D
I have access to heat treated martenistic stainless tubing for basically cheap or free through a friend in the industry. i am planning on building a cage for my xj, and i thought why not use it instead of dom or hrew?
it will have a tensile strength of about 200,000psi (1399MPa) and a yield strength of about 150,000psi (1070MPa) and 34% elongation at break. obviously much stronger than cold roll steel.