Question on muriatic acid

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larrycameron44
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Re: Question on muriatic acid

Post by larrycameron44 »

Well yes but you would have to leave it in for weeks.
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Re: Question on muriatic acid

Post by jmsrbrt »

That's why soaking in muriatic acid aids in the cleanup of dross. Those small pieces are actually "melted" (not the correct word) away to point where it's easier to clean. Overnight is probably long enough of a soak.
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Re: Question on muriatic acid

Post by GoingCustom »

I made some coasters a while back for the coffee table out of 1/8". After changing the patina on them several times over the years, I finally decided, well, my g/f finally decided she wanted them polished. So I put them in the acid bath. Couple weeks went by before I remembered I had put them in there lol. Finally had some time to work on them and took them out of the acid. The flat surfaces were fine, but the cut edges had several holes/pits almost like pumas rock sorta thing. Doesn't bother me, but now that I've made a long story long, yes it will damage the metal. Usually I leave stuff in there less than 48 hours without problem.
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Re: Question on muriatic acid

Post by jimjimmac »

I stayed away from the acid because of storage and the smell. Sounds crazy, but It was suggested to me a couple of years ago to put the things I cut from hot rolled steel that has the mill scale into one of those plastic bins like you can get at Menards, Home Depot, etc., and dump vinegar over them and let them sit over night, just enough to cover the piece(s). The next day you will see little bubbles from the acid reaction with the steel. Then you can take a rag and WIPE the mill scall right off. Yes, WIPE, not grind or scrub. I have been doing it ever since. Then I dry the piece and it is ready for grinding down to a bright silver.

Use either white or brown vinegar. They both have 5% acid. Not only does it release the mill scale, but any dross also gets loosened up and just chips off or flys all over the place if I hit it with a wire brush on my angle grinder. The acid somehow breaks or loosens the bond between the steel and the dross. You can use the vinegar a second time too, but after that it gets weak and real dark and ineffective from the mill scale deposits.

Vinegar is cheap, you can tolerate the smell, no gloves or scrubbing is needed, it works over night, and when it can't be used any more, dump it in the woods if you live there, or funnel it back into the plastic bottle it came in and put it in the garbage. Put a small piece of hot rolled with mill scale into a cool whip container and cover it with vinegar to try it out yourself. We get the vinegar in 1 1/2 gallon jugs at Costco.
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Re: Question on muriatic acid

Post by fergy »

have seen lemon juice used to clean engine parts before they just had it in a big tub and pumped a small amount of air through it to speed up the process maybe you could get that in a higher concentrate as you could drink the stuff they was using then when you finished cleanin parts you could use on your fish and chips
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Re: Question on muriatic acid

Post by hacnwac »

does muriatic acid have any useful effects with helping to remove dross on stainless
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Re: Question on muriatic acid

Post by CNCCAJUN »

Just cleaned a 12" Cast Iron Browning Sheave to restore an old attic fan.

A new one was over $100.00.

The one that was on the 50+ year old fan was badly rusted.

Soaked in white vinegar for about 48 hours . . . It now looks like new . . .

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Re: Question on muriatic acid

Post by fergy »

some one slap me if this is dumb :idea: but could i fill my watertable up with vinegar? :?:
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Re: Question on muriatic acid

Post by muzza »

fergy wrote:some one slap me if this is dumb :idea: but could i fill my watertable up with vinegar? :?:

Geez Daniel, are you into the Friday frothy's early, must be a Sandgroper thing :lol:

Do you leave your cut parts sitting there for 48 hours, also I think you may find that although vinegar is a mild acid it would still attack your table long term.

consider yourself slapped :o

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Re: Question on muriatic acid

Post by fergy »

mmm acid mmm alli :!: :!: :!: no not good
didnt think it through to far hey
had some real good cuts today (still setting the machine up)
but from what i can see is there a real need to use the muriatic bath ?
i meen i was cutting and the dross was just falling off there was some near the leadins but that just come off with a light touch with a paint scraper
does muriatic acid clean off millscale?
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Re: Question on muriatic acid

Post by JEd »

Yes muratic acid will remove mill scale.
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Re: Question on muriatic acid

Post by azfabshop »

Anyone have any idea how well a closed poly container of muratic acid will remain usable if stored outside the shop in the shade? wondering if summer heat would cause it to evaporate or diminish the effect and dont care to keep container in the shop when done. Thanks!
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Re: Question on muriatic acid

Post by steelfx »

azfabshop wrote:Anyone have any idea how well a closed poly container of muratic acid will remain usable if stored outside the shop in the shade? wondering if summer heat would cause it to evaporate or diminish the effect and dont care to keep container in the shop when done. Thanks!

Muriatic acid, even when diluted with water, will remain stable indefinitely when stored in a sealed poly container.
Muriatic acid aka Hydrochloric Acid is actually a gas, with the gas molecules suspended in water, so evaporation & the release of the gas molecules (fumes) are what breaks it down in strength.

Bill
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Re: Question on muriatic acid

Post by azfabshop »

thanks Bill. So it should remain effective in a sealed container outside in the shade as long as theres liquid, it will remain suspended. I was wondering if it would off gas and dilute the effectiveness so the next time I used it it would basically be water.
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Re: Question on muriatic acid

Post by fergy »

well if it cleans off millscale im in just have to build leantoo on side of shed dont like the idea of 200lt of muriatic acid in the shed
What does it do to ali and SS
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Re: Question on muriatic acid

Post by jmsrbrt »

azfabshop wrote:thanks Bill. So it should remain effective in a sealed container outside in the shade as long as theres liquid, it will remain suspended. I was wondering if it would off gas and dilute the effectiveness so the next time I used it it would basically be water.
My tub of acid is outside in a plastic container with lid, covered with a plastic tarp and in the shade. It seems to get diluted somewhat, the more parts I soak in it. I "freshen" it up from time to time with more acid, but eventually I outgrow the tub.
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Re: Question on muriatic acid

Post by azfabshop »

great I'll try it then thanks! I wasn't too fond of the thought of storing it inside the shop
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Re: Question on muriatic acid

Post by Charlene »

I just tried the vinegar and it worked perfect! I like the idea of not having to deal with the negative parts of acid.

Thanks!
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Re: Question on muriatic acid

Post by jimjimmac »

You got that right, but don't be surprised if people come into your shop and ask if you're making pickles. :lol:
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Re: Question on muriatic acid

Post by GoingCustom »

after reading this thread and seeing what the acid did to some 1/8" I had left in acid for a couple weeks, I decided to see what it would do to some 16 gauge. Here's a piece left in the acid for about 5-7 days.

Image
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Re: Question on muriatic acid

Post by fergy »

nice effect :)
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Re: Question on muriatic acid

Post by rottenleonard »

Well I broke down after reading on here about muratic acid and went to home depot and picked up a gallon. mixed it 1-1 in a bucket and threw in some 18 ga parts I had cut out of some sheats that had surface rust, they had a fair amount of dross on them. After letting them soak for about 4 hrs I went to check on them and couldn't be happier, no dross, no rust and they almost looked like they had been glass beaded. I didn't get them dried out fast enough and they surface rusted. So i threw them back in the acid and they came clean again, this time I rinced them and then let them soak in some used antifreeze i had in the shop. I then rinced them and blew them off. good to go!!, Anyone else have a good antirust solution for post dipping parts?

Anyhow if you haven't tried this go to home depot and get some you will be glad you did.
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Re: Question on muriatic acid

Post by muzza »

I don't know whether your Muriatic acid over there is more diluted than what we buy here as Hydrochloric acid but I use mine at about 10 parts water to 1 part acid (same ratio as recommended for brick cleaning) and parts come out clean in 3 to 4 hours depending how bad the dross is, real bad light gauge stuff I sometimes leave overnight. If I need the part in a hurry I find that if I soak it for about an hour the most of the dross with rub off by rubbing 2 parts together or using an off cut like a scraper. Mill scale usually only needs to be soaked for about an hour. I have even forgotten about stuff and left it in for the weekend and come Monday pulled it out and was fine.

Here in Oz we can buy either Hydrochloric acid which is $15.00 for 5 litres (about 1 1/2 US gallons) or 35% for $13.00 so I buy the stronger stuff and dilute it more in the acid bath.

With smaller parts I have another container with Sodium Bicarbonate/ water solution I also rinse the parts off in to neutralize the acid then rinse with water and blow dry, larger parts I just rinse with water and then blow dry.

If the customer wants the parts to go rusty I don't rinse it off and just let it dry naturally.

Murray
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Re: Question on muriatic acid

Post by abmetal »

For the guys that use muriatic acid......who uses it diluted and who uses it straight?

Allen
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Re: Question on muriatic acid

Post by jmsrbrt »

Diluted 50/50
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