Tube vs. Pipe for my application

Its not life threatening in any way IMHO. I have built 3 circle track racecar cages out of 1 1/4" sch40 and 1 1/2" sch40. I have taken some serious hits on all of them with no injuries, and acceptable levels of deformation. I would build stuff out of pipe all day. I would suggest buying it from a steel yard and not Home Depot though... there are different grades of pipe.

FYI HREW and DOM are rated within 2% in strength of each other, and HREW and pipe are made using the exact same steel and processes, just different dimensions and pipe is not "officially" rated. The only pipe cages you will see fail are the ones that are very poorly designed or with very poor bends from using a crappy bender. Using a Harbor Freight bender is not the ideal way to build a cage, but if you follow some guidelines, your bends will be fine...

Straight from the Ryerson Catalog:

1.25" sch 40 pipe:
1.66 O.D.
.140 wall thickness
2.27 lbs per foot

60,000 psi tensile strength
35,000 psi yeild strength

1.5" HREW tubing:
1.5" O.D. (duh)
.156 wall thickness
2.23 lbs per foot

ASTM A513 Type 1 or 2

45,000 psi tensile strength
32,000 psi yeild strength

thanks for that, that is some great real world info.

its absolutely coming from a steel yard, my family owns and operates a local steel yard fabrication business. i can get all the sch40 i want for free basically

HeavyMetal said:

thanks for that, that is some great real world info.

its absolutely coming from a steel yard, my family owns and operates a local steel yard fabrication business. i can get all the sch40 i want for free basically

Click to expand...

But you cant get DOM?

racer32 said:

Using a Harbor Freight bender is not the ideal way to build a cage, but if you follow some guidelines, your bends will be fine...

Click to expand...

Would you care to elaborate on some of the guidelines us poor folks with the ol' pipe "crushers" could use? :laugh:

I haven't used pipe simply because I can get DOM and it is not too expensive. My only input would be DOM would have a higher re-sale value if you ever decide to sell it, otherwise cage design and weld quality are everything, you probably already know but try to keep the seam on the inside of the bend, obviously multi-plane bends it is not possible to have them all inside. good luck, post some progress pics.
Chris

steelmen said:

But you cant get DOM?

Click to expand...

for free? No

also they dont just have DOM lying around the yard.

the whole point im asking the question is to decide whether i should spend a lot of coin and special order something. or if i can just use the sch40 thats lying around in 20 foot lengths for free, and i was tired of all the cliche' recycled answers people just give with nothing to back it up other than "its what i heard"

Skullvarian said:

I haven't used pipe simply because I can get DOM and it is not too expensive. My only input would be DOM would have a higher re-sale value if you ever decide to sell it, otherwise cage design and weld quality are everything, you probably already know but try to keep the seam on the inside of the bend, obviously multi-plane bends it is not possible to have them all inside. good luck, post some progress pics.
Chris

Click to expand...

for sure, there will be pics and progress and all that good stuff

That's been hashed and re-hashed soooo many time here, there was a guy awhile ago who had alot of the same thoughts as you do, but he was gonna build his out of square tubing, because he had access to alot of it cheap.

That was a fun thread! whatever happened to that guy?

But seriously, many believe it can be done and with proper construction and welds, a strong cage can be built. Will it be as strong as DOM, probably not, would it protect you in a multiple high speed rollover end over end, no.

Will it hold up fine for 90% of the flops and mild rolls we crawlers experience, I believe so.

this jeep wont even be in the realm of anything high speed low drag related

no hardcore climbs, no intense rock quarrys. all of that is entirely out of the question in the scope of this build. thats the only reason i bring the question of cheap available materials into the mix

Georgia Mike said:

Would you care to elaborate on some of the guidelines us poor folks with the ol' pipe "crushers" could use? :laugh:

Click to expand...

Sure-

Look at your HF dies and make sure they fit the pipe correctly. There should be no gaps anywhere around the "top" of the die @ the centerline of the pipe. If your dies fit well and you are still expreiencing some mild kinks, bend slower. If you go too fast, the pipe will kink. If worst comes to worst, cut some cap plates out of 3/16, cap one end of the pipe, fill the pipe with some good silica sand and cap the remaining end. Any shop with sandblasting supplies should have bags of good silica sand for a couple bucks a bag. Cut and fit all your intersections tight and make lots of triangles...