I cleaned my brake with CLR and

[hogpatrol]

I did an ultrasonic clean on one stainless brake using brass cleaner and distilled water and it turned the brake almost black. Use the same method with all my other brakes and never had the same result. Only thing I can figure, could have been cheap foreign steel with different chemistry.

 

[Nick Caprinolo]

Don't think I would use a wire brush. It will probably scratch it. Try a buffing wheel with a mild abrasive such as rubbing compound for an auto. On the other hand, having it beed blasted should be a very inexpensive process and might be the best course of action.

 

[hogpatrol]

A scotchbrite wheel in a bench grinder is another option. Dremel setup would use these:

https://amazon.com/Rocaris-Abrasive...DL,B07T1M9KC1,B00063VT0G&srpt=ABRASIVE_WHEELS

 

[PopCharlie]

I used CLR to clean carbon out of a pistol barrel. It was from a Rock River 1911 in 9mm. It got the carbon out, but discolored the outside surfaces of the barrel. I was able to use a dremel with a buffing wheel to restore it. I also polished the feed ramp while I was at it.
I have used it on my BR rifle barrels with no ill effects. However, I stopped using it after the pistol experience.
PopCharlie

 

[gdbleb]

That picture looks exactly like the time I soaked a nickel-plated faucet handle in CLR overnight to remove calcium deposits. CLR destroys nickel. Says so in the fine print. No idea what the base metal is/was.

 

[coldboreshot]

+1 here for the mention of BoreTech C4. I use it on a small rag covering a toothbrush and work the brake's ports. Also a bore mop down the inside. Don't even have to remove it first. On a couple of VAIS brakes, cotton swabs through the small ports. Doesn't take very long.

 

[Dgd6mm]

Don't know if the finish had something to do with the discoloration but I soak mine in CLR overnight and neither of my 3 tuner/brakes have shown any sign of it so far.

I have left my brakes in CLR for lengthy periods of time and never have I had discoloration.

 

[0.1 Aggregate]

FWIW, here is what the manufacturer has to say about using CLR on metal items:

 

[bobinpa]

Thanks for all of the replies, I appreciate it. I was hoping someone could give me the "why" it happened. I'm not worried about getting it "fixed" so to speak. I'm pretty sure that it can be re-blasted and that will clean it up. If not, then I guess my mistake will get more expensive and I'll get another one made. I truly don't know why it happened. I know other people use CLR in the same way with way different results. So what caused this??? It is a stainless Shrewd brake. I know Shrewd isn't the best but I'm not recoil sensitive at all, I just use a brake on some guns so I can see my hits and the Shrewd works good enough for me for that.
Now, is it that the stainless is a "lesser" grade or do you think it is the fact that it was blasted or when it was blasted was some foreign material impregnated into the brake surface? I have a lot of these brakes, so I guess I'll go back to my old way of cleaning them. I just posted this so others would see what could happen or maybe someone would say that it happened because of ???? Maybe I'll try it again on a "polished" brake and just not leave it in as long and see how that goes....

 

[Sandstorm]

Its the metal composition that makes up the stainless...your likely has a higher zinc content.
Stainless comes in so many flavors...and blends if know what I mean.
Here is one excample : This is only one example...of many ..different types

304 stainless steel must contain:

18% to 20% Chromium
8% to 10.5% Nickel
0.08% Carbon
2% Manganese
0.75% Silicon
0.045% Phosphorus
0.03% Sulfur
0.1% Nitrogen

 

[hogpatrol]

Just a WAG, but are you sure it's not chromoly?

 

[ridgeway]

I did a test awhile back with soaking 416 barrel stubs in CLR and alloy testing each one. The shorter stub etched and the HV did not. Did an alloy test on each one and here is chemistry make up. This is all in another thread here.

Sporter make up:
410-416 SS
Cr=11.85
Mn=.654
Fe=86.54
Ni=.588
Mo=.364

HV makeup:
410-416 SS
Cr=11.74
Fe=86.88
Ni=.445
Mo=.318

 

[hogpatrol]

I did a test awhile back with soaking 416 barrel stubs in CLR and alloy testing each one. The shorter stub etched and the HV did not. Did an alloy test on each one and here is chemistry make up. This is all in another thread here.

Sporter make up:
410-416 SS
Cr=11.85
Mn=.654
Fe=86.54
Ni=.588
Mo=.364

HV makeup:
410-416 SS
Cr=11.74
Fe=86.88
Ni=.445
Mo=.318

Possibly the nickel is the culprit.

 

[Minshooter]

+1 here for the mention of BoreTech C4. I use it on a small rag covering a toothbrush and work the brake's ports. Also a bore mop down the inside. Don't even have to remove it first. On a couple of VAIS brakes, cotton swabs through the small ports. Doesn't take very long.

Same here.
I bought a used suppressor mount that was so carboned up, it looked like a piece of charcoal.
Wrapped it with a paper towel, soaking it well with BT C4. 24 hours later, all the carbon wiped
off clean, without harming the black nitride finish. Could hardly believe it. Looked like new.

 

[dhagerty40]

This is from the Safety data sheet for standard CLR:

Restrictions on Use: Incompatible with strong oxidizing agents, metals (except stainless steel, chrome), acids, bases, and bleach.

since there is over 20 different types of CLR and all have different chemical makeups Make sure which type you are using! What I see from your Pic, that brake was Plated (most likely nickel).

https://clrbrands.com/CLR/media/PDF/CLR-CalciumLimeRust-SDS-1-16-19.pdf

 

[Deleted Dewey]

I did an ultrasonic clean on one stainless brake using brass cleaner and distilled water and it turned the brake almost black. Use the same method with all my other brakes and never had the same result. Only thing I can figure, could have been cheap foreign steel with different chemistry.

A whole lot of expensive steel is foreign as well.

 

[JayHHI6818]

Best use for for CLR is cleaning chrome running boards on my F150. Road salt really messes them up. Spray on let sit ten minutes and rinse with water.

 

[bobinpa]

This is from the Safety data sheet for standard CLR:

Restrictions on Use: Incompatible with strong oxidizing agents, metals (except stainless steel, chrome), acids, bases, and bleach.

since there is over 20 different types of CLR and all have different chemical makeups Make sure which type you are using! What I see from your Pic, that brake was Plated (most likely nickel).

https://clrbrands.com/CLR/media/PDF/CLR-CalciumLimeRust-SDS-1-16-19.pdf

Thanks. I did not know they made different mixtures. I'm pretty sure, but not positive I am using the same as the video I saw. The brake isn't plated. It was turned down to match the diameter of the barrel and bead blasted.

 

[Bill Norris]

Best bet would be the nickel content but I'm certain that is debatable.