Cleaning and rust remover- turned my screws and nuts black

[Nevus]

I thought this was a pretty straight forward plan. I removed some
parts from the right gun assemby on my STTNG. The screws and cannon
mounting plate were a little rusted and has some lime looking
oxidation. I cleaned them with shome rust remover (phosphoric acid),
toothbrush and scotch brite pad. Rust removed good but not great.
The gun plate would not get shiny and still had a lime look to it. I
tried some CLR in the same setting. The gun plate did nothing but the
small screws all turned black. My late night googleing has failed
me. Anyone had this happen? Advice?

[Ron - NYP]

I use LLRM and leave the parts in overnight, when I take them out, I use a
piece of wire so my hands never touch it, then I take it and immediately
rinse it with water under high pressure and all the black residue washes
right off. Then I blow dry all the water off , very rarely do you need to
wire brush something this way. works for me ok.
Ron

--
www.newyorkpinball.com

Pinball Flyer Database
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"Nevus" <csock...@gmail.com> wrote in message
news:3043cb79-44b8-4f3c...@v17g2000yqv.googlegroups.com...

[Nevus]

Thanks for the reply. I forgot my Chemistry. Looking it up on Wki I
found the following.

(Edited) "Phosphoric acid may be used as a "rust converter", by direct
application to rusted iron, steel tools, or surfaces. The phosphoric
acid converts reddish-brown iron(III) oxide (rust) to black ferric
phosphate, FePO4........After treatment, the black ferric-phosphate
coating can be scrubbed off, leaving a fresh metal surface...... The
black phosphate coating can also be left in place, where it will
provide moderate further corrosion resistance. (Such protection is
also provided by the superficially similar Parkerizing and blued
electrochemical conversion coating processes.)"

I thought I had either "blued" my hardware or adding the CLR has
somehow stripped the shine away. I guess I didn't think the hardware
was completely covered in rust so I wasn't expecting a complete
coating of black. I'll try soaking overnight this evening.

[Rob Myers]

The problem with CLR is that is reacts with ZINC plated parts
horrifically. (It's OK with nickel plated, chrome plated, or
stainless steel parts.)

I CLR'd a few zinc plated parts, and believe me, it can strip that
zinc of right off and down to the mild steel beneath it. And before
completely going that far, it turns the surface zinc black; and that
black stuff does *not* rinse off easily --- if at all. You will have
to get out jeweler's rouge and a buffing wheel to handle it. It has
happened to me, so I'm not just speculating here.

CLR will react with zinc plated parts almost instantly. You can see
it start to turn black-ish, and small bubbles start to form. At that
point, it's too late. Don't put zinc plated parts anywhere near CLR.

You can use CLR on 'rusty' (pitted through) nickel plated steel, but
forget about using it on zinc plated steel.

If you want to see a similar, but even worse reaction, try using CLR
on Aluminum (no, don't try it).

This reaction I am talking about (above) has nothing to do with
converting brown Iron III Oxide to black Ferric-Phosphate. Your
chemical statement is correct, but it doesn't apply when dealing with
zinc or aluminum reacting with CLR.

Cheers,
--- Rob

On Sat, 11 Dec 2010 06:35:44 -0800 (PST), Nevus <csock...@gmail.com>
wrote:

[Nevus]

Thanks all. No CLR anymore, just to be safe. I'm not sure what parts
would be zinc or nikel coated so why guess and ruin parts.

I took the expeirment farther lsat night. I placed some leg bolts,
small screws, and two post screws in the phosphoric acid overnight.
Early on the acid bubbled and the parts got a little shiny. This
morning, all dark/blue coated (ferric phosphate?). It does not wash
off with water or toothbrush. :(

I'll glady take more tips, brand recs etc. I'm starting to think I
need to just buy new stuff.

[Ron - NYP]

I meant liquid lightning rust remover

--
www.newyorkpinball.com

Pinball Flyer Database
www.nypinball.com/brochures.php

"Ron - NYP" <rons...@optonline.net> wrote in message
news:4d036f44$0$20158$607e...@cv.net...

[jimmythekid]

Best rust remover in my opinion is apple cider vinegar.

[ovfdfireman]

I got married and mine turned blue

[duked...@gmail.com]

I've had the same thing happen to me on screws & nails. I'd like to know how to get rid of the black "residue" after using CLR. Soaking them in WD-40 might work. Dunno?

[Ken Layton]

On Sunday, March 19, 2017 at 7:35:18 PM UTC-7, duked...@gmail.com wrote:
>
> I've had the same thing happen to me on screws & nails. I'd like to know how to get rid of the black "residue" after using CLR. Soaking them in WD-40 might work. Dunno?

You either left them in the C-L-R too long, or else you mixed it too strong.

For zinc plated stuff you should mix 10% C-L-R to 90% water. Leave the screws in for about 15 minutes.

[phis...@hotmail.com]

CLR leaves nothing behind to protect the metal. A good metal polish will. I use and recommend Blue Magic. It leaves a very thin coating of silicone.

If you can't get the rust off with a tumbler and polish, run the parts through the tumbler afterward (with polish) to get a protective coating on them.

-phish

[mariaw...@mcacademy.com]

On Saturday, December 11, 2010 at 1:10:29 AM UTC-5, Nevus wrote:
> I thought this was a pretty straight forward plan. I removed some

> parts from the right gun assemby on my STTNG. The screws and cannonblah blah