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Mon Mar 30, 2009 9:24 am

I'm still trying to get into metal fabrication, but a little leary on the lingo here. I called my local steel shop and asked for:
' 2 Inch round stock steel, .090"
and he said:
' I don't have that, I've only got schedule 40, try shop xyz '

I'm not used to using schedule measurements on steel, only on PVC so far.

So what is the correct terminology I should be using? was what I said correct? I kindof know what I want (2" x .090 and something 1.5"), but I'm not sure what the correct lingo is.

Also, what is a good thickness for 1.5", just for general use like light bars or whatever. I wouldn't dream about doing anything structual yet :)

Sorry for the super newbie question but I come from a family of carpenters so I'm all alone in the metal working world!

Mon Mar 30, 2009 9:33 am

You are close on terminology.

Tubing is sized in the true thickness as in your 0.090 inches.

"Pipe" thickness is sized in the schedule table.

You will need to go to a supplier that carries tubing and not pipe. 0.090 is good for light bars. 0.120 is best for bumpers and cages.

Mon Mar 30, 2009 9:35 am

SSChicken
next time tell them you are looking for "tubing", Pipe is measured by "ID"
while tubing is measured by "OD", you never want to use pipe for any roll cage, I guess it would not hurt to make bumpers out of it other then the fact that you would need different dies for you bender for pipe and tubing.
.090 wall 1 1/2 round tubing would be fine for most bumpers I would think. I hope this helps.

Earthquake

Mon Mar 30, 2009 9:41 am

For main roll cage members 1.5 OD (or 1-5/8), .120 DOM (Drawn Over Mandrel) is probably best because its stronger then plain "mild steel" tubing and not near as expensive as chrome molly tubing....

For non-cage bracing 1.5 inch .090 wall is probably sufficient...

I believe Schedule 40 refers to PLUMBING PIPE not STEEL TUBING.... The key phrase here is "tubing" and you search should take you to steel sales & suppliers not plumbing supplies....

http://www.engineeringtoolbox.com/ansi-steel-pipes-d_305.html

And time somebody throws a "zinger" at you and infers you dont know what you are asking for do a little GOOGLE search and become informed buyer or searcher....

Dale

Mon Mar 30, 2009 9:47 am

Dale M. wrote: For main roll cage members 1.5 OD (or 1-5/8), .120 DOM (Drawn Over Mandrel) is probably best because its stronger then plain "mild steel" tubing and not near as expensive as chrome molly tubing....

For non-cage bracing 1.5 inch .090 wall is probably sufficient...

I believe Schedule 40 refers to PLUMBING PIPE not STEEL TUBING.... The key phrase here is "tubing" and you search should take you to steel sales & suppliers not plumbing supplies....

http://www.engineeringtoolbox.com/ansi-steel-pipes-d_305.html

And time somebody throws a "zinger" at you and infers you dont know what you are asking for do alittle GOOGLE search and become informed buyer ot searcher....

Dale

Thanks for all the info, helps a bunch. I asked for pipe specifically, but I'm assuming he misheard me perhaps? I can't imagine they don't have any, I called Cliff's Welding who doesn't do any (or very little) plumbing from what I've seen. They are the ones who did the upstanding job on my my windshield frame, bent a 1/8" piece of flat stock laterally around the frame o.0 Pic

Anyways, I might call them again and ask what thicknesses they have in 2" tube and see if I get a different answer. I'm guessing he misheard me or perhaps I accidently said pipe.

Thanks all for the info though, learn something every day :D

Mon Mar 30, 2009 12:13 pm

also instead of throwing around super fancy terms like CREW (cold rolled electric welded) and DOM (drawn over mandrill) use the terms, seamed and seamless.

Mon Mar 30, 2009 11:23 pm

"Seamless" tubing is another animal RLAP. And far more expensive. DOM has a seam which spirals, but the tubing is drawn over a mandrel after the seam is welded, which metallurgically reduces the effects of the seam as well as visually.

If the people at the steel supply aren't familiar with terms such as "CREW" and "DOM", I'd head to another supplier.

Mon Mar 30, 2009 11:59 pm

I did a stint out of state once, I was told it was called, NASCARTUBIN....

came back home where it is still called 1 & 1/2 095....

(still looking for that die for the tubin....)

Tue Mar 31, 2009 3:14 am

Im curious as to why he thinks that :?:

Tue Mar 31, 2009 8:21 am

Quote: I did a stint out of state once

What is your deffinition of "Stint"? Which Prison in which state?

In KY they call all of it Piipe (with emphisis on the i). I was in Western NY and they called it tobing.

In TN I heard it all called pipe. Water Pipe, Drain Pipe, Fence Pipe, muffler pipe and cage pipe.

The DOM also sizes the wall thickness very consistantly.

Tue Mar 31, 2009 9:20 am

ERW "Electric Resistance Welded" , same as CREW.

Found this on the web if anyone is interested in the different types.
http://www.zookpower.ca/forums/showthread.php?t=4593

Tue Mar 31, 2009 9:23 am

dustymojave wrote: "Seamless" tubing is another animal RLAP. And far more expensive. DOM has a seam which spirals, but the tubing is drawn over a mandrel after the seam is welded, which metallurgically reduces the effects of the seam as well as visually.

If the people at the steel supply aren't familiar with terms such as "CREW" and "DOM", I'd head to another supplier.

Funny all the DOM I have seen has a straight seam along length of tube...

Dale

Tue Mar 31, 2009 9:40 am

Dale M. wrote: dustymojave wrote: "Seamless" tubing is another animal RLAP. And far more expensive. DOM has a seam which spirals, but the tubing is drawn over a mandrel after the seam is welded, which metallurgically reduces the effects of the seam as well as visually.

If the people at the steel supply aren't familiar with terms such as "CREW" and "DOM", I'd head to another supplier.

Funny all the DOM I have seen has a straight seam along length of tube...

Dale

There is something to that.... My neighbor bought a roll bar (pre fab type) and they stated it was DOM. Looked more like ERW to me. My DOM has no seam and a spiral effect that you can faintly see going the full length of the tube. But it is definitely not a seam.

Tue Mar 31, 2009 9:56 am

Quote: My DOM has no seam and a spiral effect that you can faintly see going the full length of the tube. But it is definitely not a seam.

That is the way DOM is supposed to look. The inside mandrel smooths out the seam to where it is almost undetectable, visually and by feel and the outside mandrel does the same thing. The process rotates which produces the twisted appearance.

If it has a visable seam, and is in a straight line, it is not DOM. Someone is selling you a bill of goods.

Tue Mar 31, 2009 2:14 pm

If your building a car you need to look at OD size. The OD is what you can buy dies to bend your frame parts. I think your roll bar needs to be .095 1 1/2 OD.

Tue Mar 31, 2009 5:42 pm

Ok so yesterday I picked up a 20 foot length of 1-1/2" x 0.120 from a different proveder. Cost $55 (fair price?). My sole intention with this bit is for practice, so that's what I've been doing. Just welding tubes together, I'll be cutting this up and welding it to something else in another fashion here pretty soon, also be cutting some of the welds just to see the penetration (which I think was a little low this time around).

I'm using a Lincoln 3200HD which I have liked very much, I really have no formal training and most of what I do know comes from http://www.mig-welding.co.uk/ , though I'm planning on taking a course this summer some time.

I'm also using the 60 degree tubing notcher from Harbor Freight. It's TERRIBAD! The shaft wouldn't turn when I bought it, and it's like 1/8" off to one side. I cleaned and polished the shaft, and put some spacer washers in so that the holes are centered finally. Also the degree marker is completely off, 45 degrees actually makes a ~35 degree notch, so I'm just going to start using a protractor to measure from now on. Maybe I'll make my own scale on the notcher using the protractor as a guide. 39 bucks, though, so I can't complain too much. 39 bucks, and a little over an hour rebuilding it, polishing the shaft and bearings, oiling, etc. and I feel it will work for what I need. The ridgid bimetals I use with it kick ass, though. Not sure I'll be able to change blades since it's probably jammed on too tight, but I'll tackle that when it comes to.

Anyways, after all that babbeling, the reason I am posting is to show you my welds. They aren't perfect and I'm just asking you constructive criticism. Does it look like I've got too much/little power, feed? do I move too fast or slow? Are these welds acceptable? (not pretty >.<) They have just been cleaned with a wire wheel.

Again, this is 1.5" .120.

Thanks!

Tue Mar 31, 2009 5:54 pm

try a bit more heat (amps) the welder should have a nice steady sizzle not pop pop pop

Tue Mar 31, 2009 6:03 pm

It looks to me like you need to turn up your wire speed a little and try the heat up one notch. I use a little less than 3 for wire speed and C for heat. You can always back off to find a good setting for both.
Try to rest your gun hand on something while you weld and you will get way more consistant faster. I use both hands as much as I can.

Then again, I might be full of crap and some of the other guys I hope will say so.

Tue Mar 31, 2009 7:57 pm

Bubba 72 wrote: It looks to me like you need to turn up your wire speed a little and try the heat up one notch.

Alright now I'm up at D - 3.5, It looks alot better but doesn't penetrate the steel all the way. Isn't it supposed to? It is a smooth sizzle, also, not pop pop pop. I do notice on the other side that it is cutting into the metal, a bit, though.

Is this any better?

Tue Mar 31, 2009 8:01 pm

Slow down a little and burn through. Watch as you burn through to see just what it looks like. Then try welding slow enough to just keep ahead of burning through.

And practice, practice, practice.