Restoring metal parts with Muriatic Acid.

Mr Gorsky

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Watched an early episode of Graveyard Carz some time back and Mark told the long turd to "take those bolts out back and put them in the muriatic acid to clean them up".

Today I Googled "muriatic".

Muriatic acid is diluted Hydrochloric acid...some say four parts acid to six parts water. I couldn't find any Muriatic acid in my neck of the woods, so I just got some from full strength gear from the hardware store. Cheap.

Being cautious, I went ten percent acid (always add acid to water, never water to acid). Use gloves, goggles, sleeves, etc. Into a plastic container went the water, then the acid, then the parts.

Only do this outside in a well ventilated area. Not in your workshop. Google says that the fumes will rust everything nearby...overnight. And your lungs. Keep the kids and dog away.

Fantastic stuff. A few hours later, bingo:



Before:
latch.jpg



...and after:


latchacid.jpg




No scrubbing, no scotchbrite, nothing. Just rinsed and applied WD40 to prevent further rusting in the short term.

More pics to come.

Regards,

Mr G :cool:
 
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mmissile

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Most important part of the above.............Watch the vapors...they'll kill ya!
 

Mr Gorsky

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This lid used to look like the rest of the booster:


masterlid.jpg

 

dryheat

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Thanks for this tip Mr Gorsky ...

Muriactic acid is readily available at any pool store. I've even picked some up at a local Walmart.
 

Mr Gorsky

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Will it strip paint and will it hurt pot metal?

No, it won't strip paint.

Yes, it will destroy pot metal.

To save some time you can go 20-30% acid....just be alert to the increased fumes and more aggressive reaction when the part is in the mix. I've stuck with a 10-15% mix.

Use a second plastic container filled with water to rinse your parts a few times once you remove them.

Before:


spring3.jpg



and after:

springacid.jpg



- - - Updated - - -

Thanks for this tip Mr Gorsky ...

Muriactic acid is readily available at any pool store. I've even picked some up at a local Walmart.

Yeah, I've seen the "pool acid".

I couldn't find anywhere near me that had "pool acid" with the concentration listed on the label.....it just said "pool acid". That's why I went with full strength hydrochloric acid and diluted accordingly.
 

super-bee_ski

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I washed a garage floor a few years ago.
Thought I could "hold my breath" for a few seconds and ran out of the garage after inhaling a big breath of the Muratic Acid
To this day I still have a cough
 

flypaper

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Hydrochloric Acid "Muratic is the worst possible acid to use on any metal. it permanently damages the steel.

yup
its some really nasty stuff i would rather avoid
you don't want to get it on you and its fumes are nasty
if it gets in a cut it takes the nitrogen right out of your blood and
you will get intense pain.
it will do just as much harm as it will good
it will completly strip the plating/galvenizing right off your part clean
that graveyard car hack clown will have people destroying thier parts
if they don't have a clue about what they are doing.
even evaporust that is a very weak acid will destroy stuff if you are not careful
 

satman72

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And this would be much different from blasting a part & changing the surface structure... how? Yes when you submerge something in acid it will etch the surface, but that is typically what is done with any rust removal process. It all depends on time.
 

flypaper

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And this would be much different from blasting a part & changing the surface structure... how? Yes when you submerge something in acid it will etch the surface, but that is typically what is done with any rust removal process. It all depends on time.

comparing it to blasting
is apples and oranges
the point is there are alot safer ways (evaporust!) to restore something then using a
chemical that could really harm you or your parts.
so you save a few dollars and you are putting
yourself closer to harms way at the same time.

hey if you like it, go for it! more power to ya!
just remember be really really careful, one mistake/slip up and
you could pay for it in alot more ways then one.
its simply not worth the risk to me..
 

snakeoil24

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Hydrocholric creates heat in the presence of Iron , it dames the nicjkel content of the steel and leaves it exposed to rust even if it is painted. A safe way is to use Phosphoric acid which is available in hardware stores just look on label. You can uise Molasses, which converts into Phosphoric acid in the presences of Iron. this method is very safe and is great after blasting to remove micro rust which blasting can not get rid of all iron ox
 

Cranky

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I've used muriatic acid to clean radiators with good results.....and yup, time and dilution is a factor. So is ventilation for sure! Haven't tried to clean parts with it tho.

I washed a garage floor a few years ago.
Thought I could "hold my breath" for a few seconds and ran out of the garage after inhaling a big breath of the Muratic Acid
To this day I still have a cough
In the late 70's, I used to help my sister and BIL with their hardware store and rental property and one time when I was mowing a lot, the mower ran out of gas so I grabbed a 'gas' can and filled up the mower not knowing it was Varsol. The mower ran on it but the next time I tried to use it, it wouldn't start and upon sniffing the gas, I knew what it was. Now, knowing how he would use just about any kind of container for any kind of liquid, I did a quick sniff of the contents of the gas can he had in the garage to make sure it was gas the next time I mowed. Well, this day the gas can happened to be full of Muriatic acid and it about knocked me for a loop when I sniffed it! He got a real big piece of my mind the next time I saw that bastard as I lost a lot of respect for that jarhead that day! I was pissed to say the least and I'm pretty sure I could have killed me a marine had he been near by that particular day. From then on I brought my own gas and charged it to his property account. Dumb @#$&
 

zyzzyx

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Using any acid on metallic parts causes stress corosion cracking. At the very least, if you use it on any parts that are under any kind of stress, you should stop the reaction with
a baking soda and water stop-bath. Glass-Beading parts is much friendlier to the parts because it impacts the part with the round beads and makes the surface more dense.
Kind of like when turbine and aircraft parts are shot-peened. Fumes are "Killer".
 

Mr Gorsky

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I'm not worried about any of this stuff getting stress cracks!!

Like anything, use common sense and don't submerse anything you consider fragile or critical. I'm using a weak acid mix, taking my time and not taking risks.

Here's the latest victim:


throttlebracketacid.jpg

 

64BEL

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White Vinegar works very well and safely, as well as molasses.
 

Lets Roll

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Make sure you store the muriatic acid in a safe place too. I had a jug of it break open in my shed and it made a mess.
 

Mr Gorsky

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How long do you leave the parts in the acid?

Some parts (like the master cylinder lid) took 90 mins to clean up. The hood spring took about six hours.

Make sure you store the muriatic acid in a safe place too. I had a jug of it break open in my shed and it made a mess.

Yeah. I've stored it in the garden shed, well away from anything I care about too much :)
 
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