Removing mill scale from HR steel

I've asked the same question. The answer: A solution of vinegar and salt. Use excess salt. Dissolve as much as you can in the vinegar. If done right there'll be a layer of it in the bottom of the container.

Regards,

Orrin

Sorry, I should have googled google's groups archive before asking this question.

I will surely try the vinegar or vinegar / salt solution.

Thanks and sorry, no more responses needed.

-Tom

Had the same problem until I started ordering sheets without slag a few more bucks and well worth it. Replaced my SB cabinet this week with large version from HF retail on sale $199.00 an excellent buy thifty on air at about 9 cfm. Try carbide blasting slag excellent for powder coating about

Ken

Not challenging the muriatic acid and vinegar/salt suggestions, just surprised that such mild chemical treatments would have any effect, at least w/ some of the HR scale I see. That scale, IIUC, is a kind of oxidation product, and thus pretty stable. The underlying steel itself is *much more* reactive to different breeds of acids, such as nitric, which is probably not available to consumers anyway, not just because of 9/11, but because it is pretty nasty stuff. The suggestions tho are certainly cheap enough to try.

It's interesting that different steels from different plants have really diff. appearances. I remember buying a bit of HR angle iron (approx. 1" x 1/8) that happened to be from Korea at the time. Mills bad-mouthed it alloy-wise, but let me tell you, it had an inside radius of *near-zero*, like arch. alum, w/ zero scale! Had sort of a reddish color, which is how you knew it wasn't cold rolled, also was grainier than CR. Straight and nice. Some of the crap I see today... goodgawd....

Cold-rolled is a nice option, albeit at extra cost, but might be worth the extra $$, depending on how difficult scale removal actually is.

Just >

Oh yeah, forgot to mention, lest the other suggestions don't pan out, running flat material through a "time saver" (basically a big stationary self-feeding belt sander) will give miraculous results, even a polish w/ the right grits. Pricey machines ($3K used, smallish), not a lot of shops have them.

If the material is suff'ly narrow, you could kluge your own time-saver w/ a

Yes. H Cl ( hydrochloric ) ( Muriatic ) acid works fine. Just did a bunch of small parts at school. The kind sold in the "big box" stors as concrete cleaner, it takes a while to work but does a good job. ...lew...

Whaddya know?! The vinegar & salt trick worked.

Soaked for about 12 hours and the mill scale came off with a nylon scrubbing brush.

Awesome.

-Tom