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The last I had was from Aldo. A machine and welding shop can order it for you as well. When you get down to it, A36 will work, aw long as it's a batch that will weld to itself. I get a short bar to test this, and if it will weld I get more from the same lot.

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The manganese makes no difference in welding. 1018 and 1020 both weld just fine IF you get 'em hot enough.

 

A36 ( common structural steel) is the one that can get you in trouble. Most of the time it welds fine, but the tolerances are WAY more variable. If you get a batch with too much copper it won't weld for anything. Since it doesn't come with spec sheets the only way to find out if it works or not is to buy a small piece and see if it welds. If it does, get the rest from the same batch number at the same place. Note it is pretty uncommon to find a batch that won't weld, but it does happen. Usually found in the racks of the big box stores, since they buy whatever is cheapest at the time and a few years ago the Russians flooded the market with crappy structural steel. Some of it is still floating around.

 

Jerrod can make a better case, but the reason A36 is so variable is that the only spec required is a yield strength of 36 KPSI (thus the 36). Carbon can vary over a wide range, and tramp elements from scrap remelting are allowed in higher proportions. It does the job fine as structural steel and takes electric welding just fine.

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Jerrod can make a better case, but the reason A36 is so variable is that the only spec required is a yield strength of 36 KPSI (thus the 36). Carbon can vary over a wide range, and tramp elements from scrap remelting are allowed in higher proportions. It does the job fine as structural steel and takes electric welding just fine.

 

No, I can't; that is pretty much it. I can add that the bulk of the bad stuff in A36 comes from re-melting entire cars. Wheels, seats, wires... everything. The main elements that get in there to kill the mechanical properties is lead, tin, and copper. When you see movies where they crush a car into a tiny cube, that cube gets melted into rebar and I-beams. Now they generally don't crush the cars, they shred them. If you haven't seen a video of this stop reading this and go to YouTube immediately. So cool. This product is called slitter scrap. I will never allow this material in any foundry I work at as it produces bad metal. BTW, 36 ksi is terrible. It is crazy easy to produce steel (1025) that is twice as strong.

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Thanks guys. I was just thinking 1020 because I have seen that used and knew it would fit the bill. I didn't really think of 1018. I've ordered some of that though and am going to give it a go.

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Pretty much everything sold as cold roll is 1018/1020. One of the reasons is is more expensive than the A36 structural steel.

A lot of "cold rolled" steel is A36. You can buy cold rolled at the big box stores and it is almost certainly A36.

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If you go to a place that knows a bit about what they have (meaning not a big box store, but a place that only sells metal or a machine shop) they should be able to tell you what they have. Just be nice and ask if they have "anything like 1018 or 1020, just not A36". They should either be able to tell you what they have, or if they don't know it is probably A36.

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as far as I know none of the cold roll is A36 , I was told the inconsistency in the alloy destroys the rollers .. at least that is what i was told. in any case when I order from my steel supplier all cold roll is 1018 and all hot roll is "structural steel " (aka A36) but then I haven't bought steel at a hardware store in 20 years.

MP

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You can get 1018/1020 hot rolled and A36 cold rolled. I wish there was an easy way to know what you were getting, but sadly there isn't. Now, not all A36 is made the same. Technically 1018/1020 (and more) are A36 too. Those that cold roll A36 stuff that isn't quite up to spec for 1018/1020 likely have a specific hardness spec the supplier has to meet (at least a max, maybe a range for consistency). Cold rolled that is not 1018/1020 may still be pretty good stuff, even if it isn't exactly 1018/1020.

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Speaking of the possible flaws in A36. Here's a piece of A36 commercial quality, which looks like it's sheared from plate. I had put it in the tumbler to clean all the scale. Here's what it looked like after taking it down to bare metal. I've had A36 with a crack the entire length of 20', but I've never seen splotches before

Picture 1395 Large Web view.jpg

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