electrolytic rust removal

[T0rnado69]

Stuck a bid on the PSU I linked to above - don't anyone here gazump me......

Ohh i need a psu lol

lol i wouldnt do it to ya slim

im going to get one of those ones that wallace got.
well the new version as thats whats listed now

 

[slim_boy_fat]

^^ Got it at starting price of £12.50 + p&p.

 

[T0rnado69]

Wished that happened everytime

 

[droopsnoot]

Hmm, makes me wonder if there isn't something else wrong with the setup then, as I recall trying it soon after I bought it with no great results.

I've set the Rapid PSU up again to clean up a gearbox crossmember, and it's working much better than it did before. The significant change is that instead of using a crocodile clip on the wire to the workpiece, I now have a round terminal on the end of the wire and hold it onto the item with a G-cramp. That must be the change - the only other thing is I'm using a different bucket and it's probably not that.

 

[Turbo]

I have an earth return lead from an old welder that I use on heavy items. The 200a clamp on it makes a good connection though I normally grind a clean spot on heavily corroded items.

 

[MattF]

This is the type of scenario where the baskets come in handy. You can fair imagine what a pain it would be stringing all of these pieces individually.

 

[MattF]

Most people wrongly assume that a higher current is better, whereas in fact, a lower current over a longer time period gives far better results, depending in what it is you are trying to achieve.

That actually depends on the piece(s), level of corrosion and result desired. The finer the piece, or the more original detail desired intact once the process is over, the lower the current the better. However, on occasion, letting the setup run full pelt can be beneficial, as the formation of bubbles also provides a form of scrubbing action on the surface. It's usually at the cost of risking losing fine detail if corrosion is well set in though. In general though, keeping current low is preferable.

 

[Screwdriver]

That actually depends on the piece(s), level of corrosion and result desired. The finer the piece, or the more original detail desired intact once the process is over, the lower the current the better. However, on occasion, letting the setup run full pelt can be beneficial, as the formation of bubbles also provides a form of scrubbing action on the surface. It's usually at the cost of risking losing fine detail if corrosion is well set in though. In general though, keeping current low is preferable.

It does but hydrogen embrittlement is another problem with too high a current, especially if the part is a critical mechanical component. I didn't want to get dragged into a tech debate but I have studied the process in some detail.

 

[MattF]

Hydrogen embrittlement is only temporary.

 

[knighty]

great thread, have read from start to finish, I'll build an electrolysis tank next week (or the week after, time depending)

plan is to cut down a plastic 45gal drum and sue that, and I'll see what scrap I have to dump in it for anodes


but... does agitation make any difference? - a small pump to keep the solution moving ?

most things like this agitation helps, but I don't see it mentioned here at all

was thinking I could filter the water - maybe just stuck out of the bottom, pump into another container and have it overflow back into the main tank... so any crud falls to the bottom of the second tank ?

(pond style all plastic pump so it doesn't react with the solution at all)

 

[MattF]

Wouldn't have thought that additional agitation would make much, if any, difference. If you try it though, let us know the results between running a pump and not.

Filtering the solution definitely wouldn't hurt, but isn't a necessity. All of the crap settles to the bottom of the tank when you're not running it, so it's out of the way as such unless you stir it up.

 

[Barlidge]

great thread, have read from start to finish, I'll build an electrolysis tank next week (or the week after, time depending)

plan is to cut down a plastic 45gal drum and sue that, and I'll see what scrap I have to dump in it for anodes


but... does agitation make any difference? - a small pump to keep the solution moving ?

most things like this agitation helps, but I don't see it mentioned here at all

was thinking I could filter the water - maybe just stuck out of the bottom, pump into another container and have it overflow back into the main tank... so any crud falls to the bottom of the second tank ?

(pond style all plastic pump so it doesn't react with the solution at all)

I experimented with filtering the crud from the water, the sediment destroyed the pump quite quickly and its extremely fine so clogs filter media very quickly. If you wanted to agitate then you could use an air pump and air stone(s) but I don't think its necessary. a 12v supply will be more than enough and just give it time to do its thing

 

[GW8IZR]

If the liquid was rare or expensive it might be worth filtering to extend its active life, as its neither I wouldn't bother.

 

[Turbo]

Hydrogen embrittlement is only temporary.

I wouldn't agree with that. I had a set of external spring calipers that were working perfectly but had some surface rust. I put them in the e-bath to clean them up & when I took them out the c shaped spring on the top had went completely brittle and crumbled away! Now I never put anything in such as springs or spring steel.

 

[MattF]

If a spring crumbles, it was likely shot anyhow. Or, it may just have been a naff quality spring. Springs are actually a perfect example for hydrogen embrittlement. They'll usually be next to useless once removed from the vat. Try them in a day or two though and they'll have returned to normal. You can speed up the process by baking them. It could also just have been pure crap luck on your part. Never personally had a spring damaged as yet by the process though.

 

[T0rnado69]

and about time..

they finerly edited the description to remove
out of stock - new model arriving soon.
and put a picture up of the new model PSU.

shame they never did the web link LOL

http://www.elitemodelsonline.co.uk/...PS200ADJ-Fusion-200W-Adjustable-Power-Supply-OUT-OF-STOCK-NEW-MODEL-ARRIVING-SHORTLY

 

[The_Yellow_Ardvark]

A lot of people use washing soda, easy to get, cheep etc.
I use citric acid.
We know it will de rust normally, run a current through it and it will clean the rust of and not leave you with a mess.
Plus the mix will stay clear.

When I have done horse shoes, some have turned out a grey mat finish not black oxide.

The good thing with citric acid mix you can let it stand and use it after filtering as a base to make Copper sulphate to copper plate.

 

[T0rnado69]

well i finerly bite the bullet and ordered one..

O-FS-PS200ADJ

doing a few bits again in the bucket using the battery charger.

 

[Wallace]

well i finerly bite the bullet and ordered one..

O-FS-PS200ADJ

Good bits of kit for the money.

 

[anto]

A lot of people use washing soda, easy to get, cheep etc.
I use citric acid.
We know it will de rust normally, run a current through it and it will clean the rust of and not leave you with a mess.
Plus the mix will stay clear.

When I have done horse shoes, some have turned out a grey mat finish not black oxide.

The good thing with citric acid mix you can let it stand and use it after filtering as a base to make Copper sulphate to copper plate.

Can citric acid be disposed of down the drain in high concentrations?
Does it need to be renewed in the electrolysis bath after a while or would one batch do for a lifetime?