Thanks: 0
Needs Pictures: 0
Results 16 to 25 of 25
Thread: Brushed Stainless Rust Removal
-
2nd Dec 2020, 05:43 PM #16Senior Member
- Join Date
- Apr 2018
- Location
- Perth
- Posts
- 168
-
2nd Dec 2020, 06:08 PM #17Gear expert in training
- Join Date
- Aug 2008
- Location
- Melbourne
- Age
- 34
- Posts
- 1,075
Thought I'd look up pickling gel/paste....nitric acid AND hydroflouric acid
Full hazmat suit, gas mask, decontamination...definitely pass on that one
-
2nd Dec 2020, 06:34 PM #18Golden Member
- Join Date
- Sep 2008
- Location
- Riddells Creek, Vic.
- Posts
- 831
-
2nd Dec 2020, 08:00 PM #19Most Valued Member
- Join Date
- Jul 2006
- Location
- Athelstone, SA 5076
- Posts
- 4,255
Is this the stuff you can get off Ebay
https://www.ebay.com.au/itm/Able-Ino...9-cadbfbd0a253.
-
2nd Dec 2020, 09:59 PM #20Senior Member
- Join Date
- Apr 2018
- Location
- Perth
- Posts
- 168
Thats the stuff. when I was working we actually couldnt buy the stuff because of the dangerous goods licence and that we were a food manufacturer here in Perth.
Look at the ingredients, Hydrofluric acid and nitric acid. Hydrofluric will readily enter the body and start eating your bones. And burn the skin.
Scary to think you can buy it on ebay.
https://ehs.unc.edu/chemical/hfa/
-
3rd Dec 2020, 06:49 AM #21
-
3rd Dec 2020, 09:07 AM #22Member: Blue and white apron brigade
- Join Date
- Feb 2006
- Location
- Perth
- Posts
- 7,183
I have had two mild HF acid burns. A drop of concentrated HF must have got through the seams of a double pair of gloves onto to a spot on my right hand between the index and ring finger. I did not notice it until several minutes after when I was exposed (handling 500mL bottles of HF, it was the only acid I handle at the time ) and by then I was out of the lab. It started out as a mild burning sensation and I absentmindedly sucked on the spot (turns out you mouth is relatively safe due to all the Ca++ ions floating around there, the precipitates small amounts of the fluoride ion as CaF2). The pain increase and I then went to the Uni medical centre and they injected the site with a Ca solution and slathered a Ca gel over the site which had now turned red. The pain diminished over about 10 minutes and the only after effect was a loss of a 1c size area of skin around the site. The second exposure was on a finger knuckle of my left hand same problem with Plastic gloves This time I saw it happen and we had a HF first aid treatment pack in teh lab and applied the gel and the went straight to the med centre where they did the injection. Much less pain this time. The absorption of the HF depends on how much oil your skin has built up on it.
After this we changed the lab protocols and used nitrile rubber glove covered by a tough plastic glove, safety specs replaced by full face shields, and a perspex safety shield. We used to make/distill our own concentrated HF, nitric, perchloric, and HCl acids.
The nitric is also pretty nasty. The worst one was, unbeknownst to me, a drop of concentrated nitric fell onto my cloth shoe coverall and burned a 5mm diam hole right through the coverall, leather trainers, the sock and the nail of my big toe . This took about 20 minutes and only when it hit flesh did I notice, excruciating pain like someone had poked a red hot needle into my toe.
The whole nail eventually turned yellow and fell off.
I also got some acid onto the inside upper arm of my lab coat which soaked through the fabric and burn off an area skin about the size of a 20c piece. It must not have been that concentrated because I don't remember it hurting that much.
Lots of other acid incidents in 30 odd years.
-
3rd Dec 2020, 06:52 PM #23
My time in a lab was limited to uni days. Mainly molecular biochem- working with animal cells, playing with centrifuges, gels, and all the fun serums which are made from cow pancreas, placenta, and aborted fetuses.
In my experience, it was always a case of 'read the MSDS' which as a 20 y.o. was no fun at all.
IIRC for HF it is Calcium Gluconate gel. Get a burn and rub it in until you use the whole tube, then hopefully by that time you are in emergency.
-
3rd Dec 2020, 09:13 PM #24Novice
- Join Date
- May 2018
- Location
- Brisbane
- Posts
- 12
ss steel tarnish
It’s hard
All you want to know and more about stainless steel can be found in papers on the sites of the manufacturers of the product.
Sites like Austral Wright (australwright.com.au) and Silcotek (silcotek.com)
I know they have good documentation as I have used their product for many years
Don’t bother with the snake oil merchants. The actual manufacturer of the stuff mostly have good research papers on their products.
Rain water is acid Been that way since it was invented.
Unpolluted rain water PH 6.8 – 5.5
Polluted rain water Maybe down to PH 4
Extreme pollution Rains sulphuric acid
Sea water is salty (basic) PH 8.1 8.2 or there about.
Contains all the halogens. All 5 of them. Some hydrogen sulphide will be floating around also. Comes with the territory.
Stainless steel isn’t stainless as noticed
Why does stainless steel tarnish? Clue: Lugi Galvani circa 1780
You have two options.
Best option. Learn to love patina. Patina good pretty
Or
Clean it off and have a job for life.
Best way to clean it would be to get a stainless steel cleaning pro in to clean and seal.
The have all the gear to do the job.
Can the patina be removed from stainless steel? Phosphoric acid and Acetic Acid is the goto.
Acetic acids works too by a different reaction.
Which is best depends. If one doesn’t work well try the other.
How effective depends on how heavy a layer of patina has to be removed.
How long before the patina returns? Immediately
That is how stainless steel works.
How long before the tarnish returns? Immediately
Wash down with demineralised water and alcohol (metho) to neutralize the electrolytes and slow the return until the electrolytes are replaced by the sea breeze
There are coating available to stop the tarnish. There may be on suitable for your situation. Probably a good idea to have a pro do that. A bad application may give grief. All coatings have a life and require maintenance
Seems like you may have a fair area to cover. Better start soon because you will be there for a long time. You will probably need to get some tooling together to do the job. Doing it all by hand probably wont be fun.. When you finish it will be time to start again.
Or learn to love patina
Have fun with that.
SAM_0913.jpg
-
8th Dec 2020, 12:27 PM #25Diamond Member
- Join Date
- Oct 2008
- Location
- N.W.Tasmania
- Posts
- 1,407
It may be worth your while investigating electro polishing. That will remove embedded ions which will lead to rust. The trouble is, it will also remove the brushed finish, and you would have to re-do that finish, but perhaps you could do that with scotchbrite say, to avoid contamination with Iron (Fe) ions. I don't think that it will be practical for large areas, but small parts maybe.
Similar Threads
-
Rust removal by electrolysis
By 19brendan81 in forum METALWORK GENERALReplies: 42Last Post: 8th Sep 2015, 12:40 AM -
more rust removal
By morrisman in forum METALWORK GENERALReplies: 61Last Post: 2nd Jan 2015, 01:14 PM -
RUST REMOVAL - CLR?
By jim47 in forum METALWORK GENERALReplies: 10Last Post: 26th Sep 2014, 01:29 PM -
Rust removal Evapo-Rust
By neksmerj in forum METALWORK GENERALReplies: 7Last Post: 22nd Jul 2012, 01:26 AM -
How To: Brushed Stainless Finish
By Jarh73 in forum WELDINGReplies: 8Last Post: 6th Feb 2012, 08:51 PM