Hot rolled or cold rolled sheet metal

Are there any recommendations I’m cutting a lot of 16 and 14 gauge sheet metal. Does anyone have a recommendation whether to use hot or cold rolled steel.

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It’s really up to you. Honestly I prefer cold rolled because it doesn’t have that stupid mil scale on it, but it is more expensive

If you use hot rolled, a half hour bath in muriatic acid solution is enough to get rid of it (50:50 mix with water - you can add propylene glycol or isopropyl alcohol to keep it from freezing if that’s an issue). Then just rinse with water (you can also do a dip in a sodium carbonate - baking soda solution to counteract the acid but a good water wash is enough).

You can get a plastic tub from a farm store like Tractor Supply or a small water “pond” from Home Depot that will hold the 2x2 stock we can fit on the Crossfire. You only need a few inches of solution - just lay the steel in the tray and have the solution cover it.

The scale dissolves and you’ll have nice clean steel.

One thing though - keep your tray & solution covered. The fumes will attack any unprotected metal nearby. You should also use a respirator if you’re spending much time doing this. Always wear nitrile gloves.

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Thank you I appreciate that

thank you guys I really appreciate your input I’m not sure I want to deal with the ass that I got enough products and chemicals and stuff laying around here that I’m dealing with and I buy my sheets 4 by 8 and have them cut into two by two squares I think I’ll just spend the money and go with Cold rolled

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Yeah, I tend to do cold rolled too - less stuff to worry about. But the mill scale does help to keep surface rust from forming.

Check with your steel supplier for hot rolled picked and oiled plate and sheet steel. Its hot rolled that they have already removed the millscale with acid, and oiled to protect it. Price is better than cold rolled.

I get my steel from Online Metals and they don’t have P&O as an option. Their cold rolled is only 10% more than hot rolled so I tend to go with that.

Wouldn’t pickled & oiled require an acetone cleaning before painting or powder coating?

Need to acetone or solvent clean cold rolled too. It comes with a protective oil coating.

First time with all this and I have bought a Hot rolled 4x8 sheet 14 GA. Got it home and plasma cut it into 2x2 sheets.
Upon further inspection I found each 2x2 has a bow in it or has warped.
Is there less chance of warping with cold rolled?
How can I avoid this as it has been a PITA!

Ive been using hr as well and had the same issue, it shouldnt change from hr to cr. I’m going to use a cut off wheel to see if that helps as ive only used plasma for cutting those 4x8s down and will report back.

Have your metal supplier shear it into 2’X2’ pieces. Mine does it for free.

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I wish mine was free, they charge almost 15 per shear… But they are also less expensive material wise than anywhere near me.

Just for reference, I bought a full sheet of 16 ga hot rolled today for 72. And a sheet of 20 ga for 40.00.
I sliced them into 2x4 pieces with the plasma cutter and put them away for stock.

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5x10 sheet? Or 4x8?

Same sheet size for both the 16 & 20ga?

Not sure on your locations but Richmond VA I got my CR 16 GA 4x8 for 68 and 14 GA for 84. But like I mentioned they just charge more for cutting it so I just take them in half to get 2x8’s and just shift it down for the next cuts.

I have not been doing this long, but my instinct said go with the cold rolled. And after working with both for a short period of time. There is no comparison, I like to work with the cold rolled - Its just more workable ( sandable/finishable )and less dross - regardless of cutting the mill scale with muratic…

I like cold rolled too - the time savings from cleaning the mill scale makes up for the extra cost. Although having a sand blasting cabinet helps speed that up (I use 80 grit glass bead).

But if you want an easy way to remove mill scale without using muriatic acid you can use cider vinegar - soak your piece for 24hrs and you can wipe it off. Not as hazardous as muriatic acid.

I think they do not differ much in working with both of these sheets, but I prefer to work with cold rolled because of the speed of working with cold rolled.