I am planning to build a cage for my FJ40. Is it worth it to spend double the $ for the DOM Tube vs. the welded steel tube. Prices I am getting here in Minnesota are 1.75x .120 wall on both

DOM is $3.30 a foot
Welded seam is $1.84 a foot

The way I understand it is the DOM is more consistent as to thickness variations but for a roll cage are both relatively the same strength and does it really make a difference on a street driven tail rig. This is my first off road rig and a family oriented event for me.

Thanks Tim

hrew hot rolled eletrically welded and dom drawn over manderal tube. hrew is use ond stock wrangler rolcages. hrew is k to use ive seen it used with graet resualts. i would use hrew if u arent gonna roll it alot. the otherr factor is overtime dom will last/sustain more rolls

hrew hot rolled eletrically welded and dom drawn over manderal tube. hrew is use ond stock wrangler rolcages. hrew is k to use ive seen it used with graet resualts. i would use hrew if u arent gonna roll it alot. the otherr factor is overtime dom will last/sustain more rolls



I hope to never roll it but off road anything can happen.:D

I am planning to build a cage for my FJ40. Is it worth it to spend double the $ for the DOM Tube vs. the welded steel tube. Prices I am getting here in Minnesota are 1.75x .120 wall on both

DOM is $3.30 a foot
Welded seam is $1.84 a foot

The way I understand it is the DOM is more consistent as to thickness variations but for a roll cage are both relatively the same strength and does it really make a difference on a street driven tail rig. This is my first off road rig and a family oriented event for me.

Thanks Tim IMO DOM is mandatory for a rollcage and if there is a question it would be should I spend the extra money for cromoly vs DOM ?

The HREW has a seam which leaves it prone to fracture or fatigue
when stressed

with you stating it is a family oriented event you should be able to answer your question with another question ..is your family worth the extra investment ?

I hope to never roll it but off road anything can happen.:D

most rollover incidents are not planned outings !! :D My .02

IMO DOM is mandatory for a rollcage and if there is a question it would be should I spend the extra money for cromoly vs DOM ?

The HREW has a seam which leaves it prone to fracture or fatigue
when stressed

with you stating it is a family oriented event you should be able to answer your question with another question ..is your family worth the extra investment ?



most rollover incidents are not planned outings !! :D My .02

I agree with Tony here and have first hand experience with rolling under both circumstance. Not to mention you very well may be spending dollars to save dimes any ways. One hard flop or grind against a rock and HREW is going to be dented. It's likely you will be redoing your cage, all or part. It's not a part of your car you want to try and save $ on. My 02

Justin

If you use 100 feet of tube on your cage, the difference is only $146.

I used hrew on the first cage in my commando. It lasted about 6 years of abuse. Then the last rock race I did, I endo'ed the rig and wasted the cage. Lucky I didnt die! The new cage I built is now DOM. No more worries, and an expensive mistake.

I have built a few cages with both DOM and HREW. I figure my life is worth the extra few bucks (And my wife's is DEFINITELY worth it). Spend the cash on the DOM and remember triangulation is your friend. Even with a regular DOM cage without the proper triangulation, you can be screwed.

I have rolled my rides with both. After splitting a tube, I will never use HREW again

Dima

be glad your paying $3 a foot for dom, its $7 and up here.

One of the best reasons for using DOM is that you can get 1.75" by .120 wall. When you get HREW, it's really a nominal 1/8" wall thickness (variation exists because of the seam. Even if there was no seam, however, it would still be about a .125" wall.

On HREW, the OD is much more accurate than the ID because it's processed through external rollers. The outside is accurately round and the diameter is accurate.

The interesting thing about 1.75" by .120 wall DOM is that the ID is accurately 1.510". That means you can get 1.5" by 1/8" wall HREW and slip fit it into the inside of your DOM. This is EXTREMELY useful for doing butt splices. If you can do butt splices on an inner tube, then you can fix F ups, you can reduce the complexity of building 3D bent structures, and you can make some segments of your build double thickness for extra strength.

You can't do that with HREW, because of the seam, and because the ID is too tight for a slip fit, and it isn't accurate even if you grind out the seam somehow.

If you want to economize, you can do external tubes which will actually take hits using DOM, but then do internal bracing, seat rails, shock hoops and other things that aren't armor surfaces out of HREW. HREW's plenty strong. It just doesn't have the resilience of DOM which is made from a slightly different alloy and gets work hardened in the process of manufacture.

One of the best reasons for using DOM is that you can get 1.75" by .120 wall. When you get HREW, it's really a nominal 1/8" wall thickness (variation exists because of the seam. Even if there was no seam, however, it would still be about a .125" wall.

On HREW, the OD is much more accurate than the ID because it's processed through external rollers. The outside is accurately round and the diameter is accurate.

The interesting thing about 1.75" by .120 wall DOM is that the ID is accurately 1.510". That means you can get 1.5" by 1/8" wall HREW and slip fit it into the inside of your DOM. This is EXTREMELY useful for doing butt splices. If you can do butt splices on an inner tube, then you can fix F ups, you can reduce the complexity of building 3D bent structures, and you can make some segments of your build double thickness for extra strength.

You can't do that with HREW, because of the seam, and because the ID is too tight for a slip fit, and it isn't accurate even if you grind out the seam somehow.

If you want to economize, you can do external tubes which will actually take hits using DOM, but then do internal bracing, seat rails, shock hoops and other things that aren't armor surfaces out of HREW. HREW's plenty strong. It just doesn't have the resilience of DOM which is made from a slightly different alloy and gets work hardened in the process of manufacture.


Are you a doctor or a steel salesman?

Are you a doctor or a steel salesman?


I'm a technophilic polynerd.

I'm a technophilic polynerd.

Stating it that way is triple redundant.:flipoff2:

Stating it that way is triple redundant.:flipoff2:

"Always have a back-up for plan B." was the motto, when I worked in the department of redundancy department.

I'm a technophilic polynerd.

:laughing:

I was asked to weld up a cage kit that a guy had ordered from jegs a few weeks ago. I was a little surprised that the kit was hrew tubing.

Guess I'm cheap :rolleyes:. I have a well designed HREW cage and don't lose any sleep over it. My rocker/ steps are double-sleeved and have still dented. There's no doubt that DOM would have dented as well in those locations, from those hits. A hard enough roll will tweak or dent a cage no matter what it is made out of. Cages are built to save your life once, if needed.

I want to build a cage out of 1.75 x .09 wall for weight reduction. I do not plan on using the cage except the one time it saves my life.

As always you have to answer the question of "what kind of wheeling are you interested in". If you want to do the hammers and get it in rocks like that, it is different than if you are a more casual wheeler.

Me, I snow wheel, deep snow and I always keep it on all three's. Weight is an issue more than using the cage for regular wheeling.

Scott

Guess I'm cheap :rolleyes:. I have a well designed HREW cage and don't lose any sleep over it. My rocker/ steps are double-sleeved and have still dented. There's no doubt that DOM would have dented as well in those locations, from those hits. A hard enough roll will tweak or dent a cage no matter what it is made out of. Cages are built to save your life once, if needed.

This is really the heart of the matter, right here.

On the one hand, there are streetable 4x4s which get tested on challenging trails and even get the occassional body damage, but a full flop would be a big deal disaster. These get "save your life" cages, often internal to body metal, akin to track racers. A fair number of these cages will bolt down to the body, as they're primarily designed to maintain a survivable occupant space and not so much to reduce vehicle damage.

On the other hand, however, there are rigs that are built to drive more tenuous lines, and for these, flops are regular occurrances. Although many of these are truly "tube frame buggies", many of the so-called tubed buggies still have chunks of an original 4x4 inside... including sections of frame and a VIN from the original vehicle. Others are much more identifiable as a (highly) modified commerially manufactured 4x4. Many of these are caged by welding into what's left of the frame, through or around what's left of the body.

I would hardly say that in the second style of build, the cage is designed for a one time use.

So, theres probably some apple/orange comparisons to iron out.

Given the appropriate design goals, and adequate building methods, there's nothing wrong with HREW or thin wall or even 1.5" tube. There just has to be a realistic assessment of what sort of expectations the user has of the end product. Then, the right material can be chosen.

Summary. you get what you pay for (literally). If you are starting the build on a cage on a family rig, I would say do it good once and do not worry about it later. I have buddies ith HREw cages that fared well on occasional flops and rolls, and some that did not so well. The cages did tehir job, but crumbled in sections. Design? triangulation, craftsmanship, build difference? Sure. But the difference in price is very small. If you build a HREW cage, and bend it and have to redo, might as well go a little stronger and uniform, and go DOM now and make it last longer. Most crazier rigs start as a family rig and evolve as your driving skills and wheeling balls grow over time :D

Will a HREW survive long on a mainly street driven rig with occasional offroading? Sure. but for about a hundred bucks extra you can go a little stronger and not to have think back about this argument after you flopped and the cage got slightly beat.

In contrast, there are those here running cages made fully of poo pipe and swear by them ;)

I was waiting for the poo-pipe reference to show up here:laughing:

To head back to the DOM vs welded tube debate, my reading on this has lead to two things:
1) DOM is stronger than welded given the same weight of material.
2) The seam in welded tube is a natural failure point.

In terms of cages, the key concern to me is the seam and splitting there. I can't say if this is a common issue or not but I'd rather not find out while trying to save some $$$ on a cage:homer:

If a cage is about 100 feet of tubing, how much are you really saving between DOM vs welded tube of the same given size?

Basically for about $150 he could have DOM (from teh price he posted above). Again, I am sure a lot of people wheel hard here with HREW cages, sliders, etc that survive a good beating. But still for that much difference, and considering teh same design and fabrication efforts, I would rather skip on MCD's and coffee for some time and go with DOM. I like to save $$ like the next guy, but on stuff to protect my nogging and my family's the answer is pretty obvious.

I am building a cage for the project #2 (family rig on tons), and the DOM is already piled up and ready to be bent :D

Most of the DOM in the grades and sizes commonly used in these applications starts out as HREW anyways so the DOM still has a a welded seam, it is just not as visible so in most cases the ``issues`` around weld seams don not go away because you bought DOM...

How about conduit? I hear it's real easy to bend and with the right design and triangulation you should be good to go right?

You know that really thin steel 3/8" diameter tubing they used for the old style folding TV trays? I would think that would save some serious weight on a rig. Plus it was gold plated.

Most of the DOM in the grades and sizes commonly used in these applications starts out as HREW anyways so the DOM still has a a welded seam, it is just not as visible so in most cases the ``issues`` around weld seams don not go away because you bought DOM...

the"normalizing" through the manufacturing process does make DOM the better choice between the two

although "conduit" cages do sound "cutting edge" in our current economic times!!:laughing:

DOM is a different alloy than HREW. Although it's true that it starts off being welded into a tube, it's still apples and oranges. DOM isn't just post-processed HREW.

I don't know of many HREW failures that involve snapping along a weld. Yes, the weld is probably a "heat affected zone", but at the same time there are a lot of differences between this and the heat affected zone that you create when you do a weld. For one thing, this is done in a hot roll process where the metal is going through a heating and cooling profile completely unlike doing an arc weld on room temperature steel. Another difference is that after the weld is completed, the entire tube gets squeezed down to diameter, which changes its properties. If anyone has actually seen this stuff fail along the weld, and taken pictures, I'd love to learn more about it. I just haven't seen it and I've looked.

Interestingly, I *HAVE* seen conduit fail in what I believe was a line along it's weld. I bent up a section of 3/4" EMT once, but screwed it all up. I attempted to repair it by twisting one bend relative to the other, and it snapped longitudinally, right next to one of the bends.

Oh... and if you're all about strength to weight ratios and resilience against cyclic loads, you're going about it all wrong using metal. You need to be thinking of nature's ultimate anisotropic composite material: wood.

Clearly, roll cages should be built of laminated bamboo strips and epoxy resin.

I have bought DOM quite a few times and it has always been 1018 or 1020 mild steel. What is the difference in that and mild steel HREWs 'ingredients'? I was always under the impression that the difference was only in the process in which it was formed.

Typically, HREW is ASTM 1010 (although ATSM 1020 is also used in some cases) and DOM is ASTM 1020 (although 1018 is also used frequently). The difference is composition is primarily in the carbon content with 1010 in the range of 0.08 to 0.13 wt.% and 1020 in the range of 0.18 to 0.23%

Does that compositional difference make much difference in physical properties? My reading of the literature says "probably not much". You can find different values for parameters such as Tensile Strength (TS) and Yield Strength (YS) for 1010 and 1020.For example, efunda.com lists the TS values as 365 MPa and 395 MPa and YS as 305 MPa and 295 MPa respectively. Different sources list quite different values and one could easily argue that the different numbers are all within analytical uncertainty. The efunda YS values of 305 MPa and 295 MPa strike me as being virtually identical.

So I don't see the published mechanical data as indicating "apples and oranges". The mild steel in either grade is very similar in its properties. It is only when you start making alloy steel with significant additions of Cr and Mo that you get significant changes in the physical properties.

DOM is a different alloy than HREW. Although it's true that it starts off being welded into a tube, it's still apples and oranges. DOM isn't just post-processed HREW.

I don't know of many HREW failures that involve snapping along a weld. Yes, the weld is probably a "heat affected zone", but at the same time there are a lot of differences between this and the heat affected zone that you create when you do a weld. For one thing, this is done in a hot roll process where the metal is going through a heating and cooling profile completely unlike doing an arc weld on room temperature steel. Another difference is that after the weld is completed, the entire tube gets squeezed down to diameter, which changes its properties. If anyone has actually seen this stuff fail along the weld, and taken pictures, I'd love to learn more about it. I just haven't seen it and I've looked.

Interestingly, I *HAVE* seen conduit fail in what I believe was a line along it's weld. I bent up a section of 3/4" EMT once, but screwed it all up. I attempted to repair it by twisting one bend relative to the other, and it snapped longitudinally, right next to one of the bends.

Oh... and if you're all about strength to weight ratios and resilience against cyclic loads, you're going about it all wrong using metal. You need to be thinking of nature's ultimate anisotropic composite material: wood.

Clearly, roll cages should be built of laminated bamboo strips and epoxy resin.

Typically, HREW is ASTM 1010 (although ATSM 1020 is also used in some cases) and DOM is ASTM 1020 (although 1018 is also used frequently). The difference is composition is primarily in the carbon content with 1010 in the range of 0.08 to 0.13 wt.% and 1020 in the range of 0.18 to 0.23%

Does that compositional difference make much difference in physical properties? My reading of the literature says "probably not much". You can find different values for parameters such as Tensile Strength (TS) and Yield Strength (YS) for 1010 and 1020.For example, efunda.com lists the TS values as 365 MPa and 395 MPa and YS as 305 MPa and 295 MPa respectively. Different sources list quite different values and one could easily argue that the different numbers are all within analytical uncertainty. The efunda YS values of 305 MPa and 295 MPa strike me as being virtually identical.

So I don't see the published mechanical data as indicating "apples and oranges". The mild steel in either grade is very similar in its properties. It is only when you start making alloy steel with significant additions of Cr and Mo that you get significant changes in the physical properties.

Is There a "Doc" in the house??:D

Paging "BellyDoc" DOM thread.....:laughing:

I believe this is going to end up being an "excellent tech" thread :smokin:

"watching" to see where it goes......:laughing:




EDIT:...subcribed !!!:flipoff2:

This is exactly why I asked this question here. My family has no $ value so I ordered up 200 feet. Yes it did hurt but I want it as safe a possibly. I ordered extra for mistakes and I also plan to make some tube flares for the rear wheel opening and spare tire mound and more rock sliders mounted on the frame.


It would probably be fine with the hrew but for the extra $300 it cost me if anything ever happened I could not live with myself because I was cheap.


Thanks for the wealth of knowledge and the great debate guys I love it. Wish me well, I have a new bender ready to go and am itching to pick up my tube Saturday.


Tim

Tim, that is a lot of freaking tube, hehe :) Post up pics on what you will be doing.

This is exactly why I asked this question here. My family has no $ value so I ordered up 200 feet. Yes it did hurt but I want it as safe a possibly. I ordered extra for mistakes and I also plan to make some tube flares for the rear wheel opening and spare tire mound and more rock sliders mounted on the frame.


It would probably be fine with the hrew but for the extra $300 it cost me if anything ever happened I could not live with myself because I was cheap.


Thanks for the wealth of knowledge and the great debate guys I love it. Wish me well, I have a new bender ready to go and am itching to pick up my tube Saturday.


Tim

Document your cage build here with pictures we look forward to seeing it.

geberhard beat me to it :D

DOM is a different alloy than HREW. Although it's true that it starts off being welded into a tube, it's still apples and oranges. DOM isn't just post-processed HREW.

DOM and HREW are the manufacturing processes and SAE 1010, 1018, 1026, 4140, 4340, 8620 etc. are the material grades. Your comparison is a slurry of apples and oranges because you are mixing the two up.

The difference between a stick of 1.75" x 0.120" WT 1020 HREW and a stick of 1020 DOM is that from most rolling mills is that the HREW has been through a few additional processes to make it DOM.

Very helpful old threda form Billavista on material strength calculation, and PSI yield strength:

ASTM Grade A-53 pipe: 30, 000
1020 ERW tube: 40, 000
1020 DOM: 70, 000


http://www.pirate4x4.com/tech/billavista/Links/

Typically, HREW is ASTM 1010 (although ATSM 1020 is also used in some cases) and DOM is ASTM 1020 (although 1018 is also used frequently). The difference is composition is primarily in the carbon content with 1010 in the range of 0.08 to 0.13 wt.% and 1020 in the range of 0.18 to 0.23%

Same comments as the post above in regards to DOM, CREW, HREW etc. being a manufacturing process and SAE 1010, 1020 etc. are grades of material which indicate the chemical makeup of the material. You cannot compare “ERW” to “DOM” because the statement lacks a material grade.

Anybody who says that they built their cage out of DOM or HREW and doesn’t state what material grade they used really shouldn’t be considered a good information source as there are ~15 carbon steel material grades of mechanical tubing commercially available in DOM, HREW, CREW, SSID etc.

If you just order A513 `DOM` or `HREW` from your supplier it can be anything from SAE 1010-1020:
480998

ASTM A513 Type 1 Tensile/Yield/Hardness Requirements:
480999

ASTM A513 Type 5 Tensile/Yield/Hardness Requirements:
http://www.pirate4x4.com/forum/attachment.php?attachmentid=345999&stc=1&d=1199849647

What Type 1, Type 2 etc. means:
http://www.pirate4x4.com/forum/attachment.php?attachmentid=455429&stc=1&d=1248141113

Typically, HREW is ASTM 1010 (although ATSM 1020 is also used in some cases) and DOM is ASTM 1020 (although 1018 is also used frequently). The difference is composition is primarily in the carbon content with 1010 in the range of 0.08 to 0.13 wt.% and 1020 in the range of 0.18 to 0.23%

Does that compositional difference make much difference in physical properties? My reading of the literature says "probably not much". You can find different values for parameters such as Tensile Strength (TS) and Yield Strength (YS) for 1010 and 1020.For example, efunda.com lists the TS values as 365 MPa and 395 MPa and YS as 305 MPa and 295 MPa respectively. Different sources list quite different values and one could easily argue that the different numbers are all within analytical uncertainty. The efunda YS values of 305 MPa and 295 MPa strike me as being virtually identical.

So I don't see the published mechanical data as indicating "apples and oranges". The mild steel in either grade is very similar in its properties. It is only when you start making alloy steel with significant additions of Cr and Mo that you get significant changes in the physical properties.


Damn Jack, you musta dusted off the old phd for that response!

Perhaps the "apples vs. oranges" analogy was a bit over-much... maybe red delicious vs. granny smith would be better. All the HREW I've gotten is ASTM 1010 and the DOM has been ASTM 1020, i.e, different alloys. That's been from several vendors in my area, although for all I know, all but one of them are probably sourcing their stock from the same supplier! My understanding is that the designation starting with 10xx means plain carbon steel and the last two digits represent carbon content in .01% increments. Should I be surprised that there are other steel alloys available for the same process tubes? NO. I should have known.

However, my understanding is also that the DOM process involves "cold working" and that the higher carbon content lends itself to more work hardenability. What I understand this to mean is that the crystal architecture is altered by the process of forming the DOM tube at a temperature below a critical value at which martensite is frozen into position. This yields a harder metal after processing. I have seen different values compared for the Rockwell hardness between these two types of tube (1010 HREW vs. 1020 DOM) but I'm not at home to see if they're in my materials book. I don't think this factoid came from the book, but I don't remember what the source actually was and so I myself, become suspicious. I don't think it was the BillaVista article, but I do think it was an internet resource, and from here at work, I'm just not finding it. Perhaps I'm remembering incorrectly.

Therefore, the argument isn't really so much the tensile strength of 1010 vs. 1020, but between additional properties that differ even more after processing the appropriate alloys.

Of course, as I'm sitting here in the back of the OR, waiting for the patient to wake up, this is all extremely relevant and useful information for a surgeon to know off the top of their head, so I'm obviously THE DEFINITIVE go-to source for such information.

Whatever you do... DON'T ask anyone with actual engineering materials science training to correct my comments because that would be a total waste of your time.

In the end, my biggest interest in going with DOM over HREW for my build, like I said before, was the expectation that I'd be fixing F-ups by doing butt splices over 1.5" HREW. In fact, this was a HUGE advantage for me. The dimensional accuracy of this material is perfect for that application.

It turned out I was right, and I used this technique multiple times.

Ok... so I start the post... do a case... finish the post... and the answer is slipped in right over my head.

Type 5 (mandrel drawn) 1020... I think that "RB" means Rockwell B scale ... minimum is 80.

On the other hand, the type 1 1010 is RB 55.

Those are the numbers I remember... but I was too chicken shit to just pull them out of my ass on Pirate.

Being wrong here doesn't play well. :homer:

I guess I am tainted because I cannot fathom calling up one of our suppliers and telling them that I wanted pricing on 1.75” x 0.120” WT DOM in singles or doubles and I doubt that they would even be willing to give pricing unless I told them I wanted pricing on ASTM A513 Type 1, 1020, 1.75” x 0.120” WT in single or doubles. And their next question would be if FSB & China sourced material would be acceptable.

You are correct that the RB=HRB=Rockwell Hardness “B” scale (1/16” Ball, 100kg of force on indenter).

Another option if you want a smooth ID is flash controlled ERW where the flash or ERW seam on the ID is controlled to 0.005” or 0.010” but whether or not this is cost effective compared to DOM is really dependent on your local supplier.

Your use of the term “alloy” in regards to 1010 & 1020 throws me off because most steel is not considered a alloy steel until manganese is greater than 1.65%, silicon is over 0.5%, copper is above 0.6%, or other minimum quantities of alloying elements such as Chromium, Cobalt, Columbium, Molybdenum, Nickel, Titanium, Tungsten, Vanadium or Zirconium are specified in the chemical composition.

Here is the chemical composition chart out of ASTM A513 for an example:
481066

So I'm even using the term "alloy" incorrectly.


Great.

:homer:

My only point was that I believe that the qualities that make 1020 DOM vastly superior to 1010 HREW result MORE from the process of making the tube than from the relatively small differences in the properties of the steel that is typically used to make such tubes.

Consider three solid 1" rods - two composed of carbon steel (one ASTM 1010 and one 1020) and one alloy steel, say 4130. In terms of physical properties, the 1010 and 1020 are relatively similar while the 4130 is significantly different. To me the apples and oranges are the carbon steel vs the alloy steel. When you make tube from these three steels, a 1020 DOM will be superior to a 1010 HREW because of the way the tube is made and a 4130 DOM tube will be superior to a 1020 DOM tube because of the properties of the steel used. So yes, you need to factor both steel grade and type of tube. For some grades that are very similar in their properties, the way the tube is made is most important. For similar tube type the grade is important.

Vocabulary failure aside, (I promise not to use the word "alloy" incorrectly anymore), my understanding of the rationale for using 1020 over 1010 for DOM is that it work hardens better than 1010. My impression is that running 1010 through the same process would result in similar dimensional accuracy, but no significant improvement in the hardness. So, yes, it's the process, but the material is chosen to optimize the effect. Is that correct?

So how dose a normal guy like me that is new at this know I got good DOM or just hrew that is sold as DOM? I asked for DOM when I got the price and was quoted $3.30 then I called another place was quoted about .30 a foot more for DOM but they said I could use hrew and it would be just as good but cheaper.

The $3.30 a foot is buying through a local guy I know who is a guy I drag raced with in the past. I told him it was for a cage so I think it is good stuff.


Tim

HREW has an inner seam. DOM does not.

Vocabulary failure aside, (I promise not to use the word "alloy" incorrectly anymore), my understanding of the rationale for using 1020 over 1010 for DOM is that it work hardens better than 1010. My impression is that running 1010 through the same process would result in similar dimensional accuracy, but no significant improvement in the hardness. So, yes, it's the process, but the material is chosen to optimize the effect. Is that correct?

Almost all metallic materials can be work hardened and to be honest I would have to do some research as to the effect carbon levels would have on the increase of hardness due to work hardening as off the top of my head I am not sure what would have greater implications in regards to lattice shifts and dislocations.

If you look at the ASTM A513 specs for min yields, tensile and hardness the general trend is that as carbon content increases the percentage of increase in min. YS and min. TS becomes larger but that percentage increase in min. RB is trending down so the charts are not a real good example except to show that going from HREW 1010 to Dom 1010 increases the min. TS by around 33% and that going from HREW 1020 to Dom 1020 increases the min. TS by around 34%.
481275
481276
481277
So how dose a normal guy like me that is new at this know I got good DOM or just hrew that is sold as DOM? I asked for DOM when I got the price and was quoted $3.30 then I called another place was quoted about .30 a foot more for DOM but they said I could use hrew and it would be just as good but cheaper.

The $3.30 a foot is buying through a local guy I know who is a guy I drag raced with in the past. I told him it was for a cage so I think it is good stuff.


Tim

All material coming out of a mill is typically marked with stenciling on the tube giving you information as to the manufacturer, OD, wall thickness, grade of material used, heat number and the specification(s) it complies with etc. If you look through some of the build threads here I know I have seen some pictures that show the markings otherwise you can take a picture of the markings on the tube you bought and post them here.

For a somewhat related example the picture below shows a pipe that meets the requirements of ASME SA-53B, ASTM A-53B, ASME SA-106B, ASME SA-106C, ASTM A-106B, ASTM A-106C and API PSL1 5L-B so the markings are pretty congested:
http://www.pirate4x4.com/forum/attachment.php?attachmentid=415629&stc=1&d=1232302430

wow, i don't know where you guys are getting your prices. i just got 3 sticks of 1.5" hrew. total bill $75 for all 3. 25 bucks a stick. dom is 4x that much money. it is a difference of $300 per 100'. and i have been wheeling a hrew buggy for 8 years. rolled hard quite a few times. and i am only just now redoing the cage because it is just too beat up.

bear in mind this is a 3500 lbs toyota buggy. and i am not out doing koh speed. so yes, for the go fast stuff i would be nervous with anything less than chromo.

but lets be realistic. the price difference is substantial.

GEEZ you guys got it easy 1 3/4 dom here is 12$ a foot and the same dimension hrew is 2.41$ a foot wtf?....what are you guys getting for prices.....cuz i think they are just trying to tube me on this deal......pun intended

Just a little to add.

Hrew 1.75 .120 wall weight per foot 2.089

DOM 1.75 .120 wall weight per foot 2.090

Are you sure about those numbers? That's almost a 10% difference. Is the HREW you referenced really .125" wall?

I would believe that if there were truly a material density difference, the denser material would be DOM which is compressed as it's formed. The ridge inside the weld on HREW can't possibly represent 10% of the volume.

What am I missing?

I thought I was:homer:

Turns out I was looking at 17/8 hrew:shaking:

Hrew 1.75 .120 wall weight per foot 2.089

DOM 1.75 .120 wall weight per foot 2.090


Here is a link.

http://www.tottentubes.com/catalog/newPDFs/TottenCatalog.pdf

I'm gonna make my next cage out of brass DOM.


There are a HELL of a lot of people out there that have rolled with a HREW cage and survived.

90% of the cage living through a hard roll is design, not the difference between HREW and DOM.

I'm gonna make my next cage out of brass DOM.


There are a HELL of a lot of people out there that have rolled with a HREW cage and survived.

90% of the cage living through a hard roll is design, not the difference between HREW and DOM.


Design definitely plays a big factor, as people with poop pipe always keep proving, but if you have the option of poop pipe or HREW will you go Poop pipe? I would say with such a small price difference go as strong as you can afford. I know people that keep on having to fix their buggy tubing wishing they had just gone with DOM to begin with. Sure they survive the rolls, but having to fix a weaker material will cost more ;)

Design definitely plays a big factor, as people with poop pipe always keep proving, but if you have the option of poop pipe or HREW will you go Poop pipe? I would say with such a small price difference go as strong as you can afford. I know people that keep on having to fix their buggy tubing wishing they had just gone with DOM to begin with. Sure they survive the rolls, but having to fix a weaker material will cost more ;)
As was brought up before. Poop pipe is not a material, it is a size. If the material was suitable, I would have no problem using pipe instead of tube.

Buggy tubing gets abused over and over again. Whay didn't they just go straight to Chromo?

Not many people will "fix" a cage that has bent in a hard rollover. They'll just replace it.. This is not a buggy (unless I have missed something)

As was brought up before. Poop pipe is not a material, it is a size. If the material was suitable, I would have no problem using pipe instead of tube.

Buggy tubing gets abused over and over again. Whay didn't they just go straight to Chromo?

Not many people will "fix" a cage that has bent in a hard rollover. They'll just replace it.. This is not a buggy (unless I have missed something)

Poop pipe....thats funny :laughing:

I agree with them......the majority of the stregth in any wieght sensitive structure (things with wheels) is not in the material, but in the design of it. I have built many cages out of poopy pipe, HREW, DOM, stainless, even played with cromo and titanium in the mountain bike world. Its in the design!

Lots of missinformation in this thread. All posted meaning to help for sure but not really correct.

Dom is drawn over mandrel formed. It still has a SEAM. Dom is held to a higher standard of measure. Meaning that dom .095 has to be some where near .093-.098 for example to be called .095.

Elect weld standards are much looser. I have bought .095 that measured .088 it is never over .095.

I cant believe some of the prices posted in here for Dom. I have checked prices from coast to coast shipped and locally I pay the below prices and they are the best I can find.

Elect costs me 26.00 for a 20 ft stick. .095
Dom costs me 132.00 for a 20 ft stick. .095

I build dirt track race cars. I use Dom in the main cage of the street stock type cars that are around 3000 lbs. Elect weld in between.

In 4 cyl cages I use all electric weld. There are cages I built in 05 that have been in several different cars and rolled 3-6 different times. All of these rolls would be similar to your jeep falling off your trailer on the frwy... The 4 cyl cars weigh 2000-2600 lbs. Some cages of mine have rolled down the cement wall and then been hit in the roof and held.

I cant see DOM being needed in any jeep thats not a high speed race vehicle. Even then the elect weld you guys are talking about like .120 is quite strong.

We use as light as we can in these race cars. .095 main cage and .085 and .069 in other areas.

www.jnjfab.com is my website if you want to see the cages Ive been building.

Chromoly is brittle. It will crack at the heat effected zone near welds from flexing.

It is used when you want the ultimate in lw, but dont care about it lasting more than a season in the racing world.

Most people dont weld chromoly correctly. It needs to be welded then the whole part needs to be heated and cooled. A lot of race car builders think the heat from powder coating is enough... thats not the case. Ive seen a modified whole back half fall off a nationally built modified from a light wall tap....

the very fact that I understand most of this thread make me feel like a metal nerd.

:flipoff2: