Cleaning stainless steel.

[zardoz]

Just read that, apparently scotch brite contains aluminium oxide as an abrasive agent! Rather ironic really.

ps: does anyone know if the 'real' 3M scotch brites are any better than the pound shop cheapo's ?

 

[langy]

There seems to be a bit of a tendency for people to go completely over the top with regard pre cleaning stainless steel material before welding it, never did it myself when I was on the tools and am struggling to remember ever seeing anyone else do it either.
So long as the material has been correctly stored and hasn't been allowed to become contaminated with any foreign matter I cannot see any benefit, post weld treatment to remove surface metallic oxides is another matter of course

Me neither I just clean with a blue poly disc and wipe with acetone

 

[Jrstainless]

Hi lots of ways to clean stainless.
We never clean before fabrication always after. We have a couple of electro cleaners now they are great one is wurth and the other anopol. Saves lots of time and sweat lol. (The anopol cleaner will be getting put up for sale soon)
We used to use pickling paste then scotchbrite!
Jr

 

[KemppiFrog]

Hi lots of ways to clean stainless.
We never clean before fabrication always after. We have a couple of electro cleaners now they are great one is wurth and the other anopol. Saves lots of time and sweat lol. (The anopol cleaner will be getting put up for sale soon)
We used to use pickling paste then scotchbrite!
Jr

Since Wurth seem to badge others products, any link to the electro cleaner? I have been asked a couple of times if I have one, but assumed it was for larger production than I do.

 

[Jrstainless]

Since Wurth seem to badge others products, any link to the electro cleaner? I have been asked a couple of times if I have one, but assumed it was for larger production than I do.

Here you go:

https://eshop.wuerth-industrie.com/...;sid=SZ-UkVK-mJaRkQAHkzqKTF20qbxEOrKdmTQ-Apq0

Here's the anopol one too:

http://www.anopol.co.uk/weldkleen.htm

Hope this helps?
Jr

 

[KemppiFrog]

Here you go:

https://eshop.wuerth-industrie.com/...;sid=SZ-UkVK-mJaRkQAHkzqKTF20qbxEOrKdmTQ-Apq0

Here's the anopol one too:

http://www.anopol.co.uk/weldkleen.htm

Hope this helps?
Jr

It does!!
Things have moved on since I was asked last time.
Thanks.

 

[hotrodder]

If you've got a suitable power supply they're easy enough to make... typically 10 - 30V / 4 - 500W some are AC, some DC some offer both (to do with marking/etching and electropolishing versus 'cleaning') some woven glass fibre cloth for the pad* (as an aside it's what a TIG finger is albeit in sleeving form for cable/hose protection) and the electrolyte- buying the proper stuff probably works better than homebrewing as they'll be other stuff in there like surficants etc but the usual suspect for the active ingredient is phosphoric acid and alternatives include acetic and citric. I found citric to be slow/not work on 'burnt' welds but that might have been 'cause the power supply (a 12V battery charger) i was using was a bit weedy or because it's usually mixed with other stuff- one research paper i read claimed 40 - 50% phosphoric + 15 - 20% acetic gave the best results

* the pad type get stumped by nooks, cranies and even a plain old fillet weld sometimes. There are now brush based systems about that use a carbon filament brush instead of solid heads. Haven't got around to buying a suitable brush and having another play as toooo many other things to get on with. Google 'tigchamp' or tigbrush for some info on the brush based systems, IIRC their tech specs suggest it uses pulsed DC

 

[KemppiFrog]

So, the sort of electro polishing system a scultor was thinking I might have, would be a big tank with that mix of chemicals and the work connected to one pole and the tank to the other (or an electrode)? I got the impression they didn't have one 'cos it was very spendy. Perhaps it the amount in the tank of the size of kit they needed that cost the money.
Thanks hotrodder, I might give it some thought. I make a few boat fittings and electropolishing would be atractive.
DW

 

[hotrodder]

I think for 'proper' electropolishing where the entire part is dunked in a tank (like plating but backwards) things can quickly get into insane power supplies due to the current density. 'Real' electropolishing traditionally uses more dangerous acid blends in the electrolyte too and AIUI leaving them out slows things down lots. It's been a while since i looked into it but there's quite a few patents and other stuff about that go into detail, googling things like 'electropolishing stainless glycols' will get a bunch of them and swapping out glycols with 'ultrasonic' a bunch more

 

[hotrodder]

I'm glad this got brought up again, had a fairly quiet day as stuff that was supposed to turn up didn't so i dug out the wand i made eons ago and hooked it up to the 24V 15A DC power supply i bought a while back. This took about 30 secs using citric acid...

Pic is awful quality, in real life the half i went over with citric is bright & shiney with zero discolouration. Zero fumes noticable, very little fizzing/heat noticable either so i reckon something else adding to the electrolyte to improve conductivity might speed it up to the instant results you see in sales vids for the proper gear?

Cost... £25 for the power supply IIRC and the wand probably took 1/2 hour or so to cobble together from what was kicking about. Need to go and buy a carbon filament brush now and think about running a pump for the electrolyte from the same power supply.