electrolytic rust removal

[Screwdriver]

I just bought another Swindens. Looks like it's been used as a boat anchor!

S.

 

[droopsnoot]

Transformer based chargers? Whack a photo or two up of them. Electrolyte seems to be good in current temps, as in no freezing. My cleaning tub has iced over several times over the past month or two, but the vats haven't once, as yet.

Here's a photo of the two battery chargers, also a PSU I got somewhere cheap that I also don't seem to have had much success with.

Actually, it looks as if it might be an old version of one of these ( http://www.rapidonline.com/electrical-power/rapid-6a-ac-dc-power-supply-65048 ) and if it is, the fiver I "risked" on it was a bargain. If I can make it do something.

Milkstone is the phosphoric based stuff? One I've not tried, as yet.

Yes, that's it. I used phosphoric to paint on to some corroded bits on the shell in the form of "phDown", a hydroponics product, but milkstone remover is much cheaper. Painting it on to pitted bits that are filled with black corrosion works well - paint it on, agitate it a bit, brush with wire brush, wipe off and do again. Cleaned a nasty pitted bit to completely clean the other day, way longer than blasting but less messy.

 

[Screwdriver]

Well I cleaned out the tank and stuck the goop in a bag to drain off the water.

What's left is almost black and dries to a rusty orange. It smells like Daz. LOL.

I am assuming it must be magnetite which will oxidise back to "proper" rust. The powder is magnetic when dry and I am tempted to dry it out and find a use for it.

Any ideas? Pretty sure it's ok to dump it in the garden, after all it's just a very pure form of dirt.

S.

 

[MattF]

Here's a photo of the two battery chargers, also a PSU I got somewhere cheap that I also don't seem to have had much success with.

That Rapid looks like a nice bit of kit. Should be good for running the vat.

 

[MattF]

I am assuming it must be magnetite which will oxidise back to "proper" rust. The powder is magnetic when dry and I am tempted to dry it out and find a use for it.

Any ideas? Pretty sure it's ok to dump it in the garden, after all it's just a very pure form of dirt.

S.

I'd bin it, personally. A lot of it will be iron based, but there'll be other crap from paint and the like in there too.

 

[Robotstar5]

I am assuming it must be magnetite which will oxidise back to "proper" rust. The powder is magnetic when dry and I am tempted to dry it out and find a use for it.

Any ideas? Pretty sure it's ok to dump it in the garden, after all it's just a very pure form of dirt.

With the right packaging and sales pitch you could make a fortune selling it as a high end beauty product

 

[slim_boy_fat]

Any ideas? Pretty sure it's ok to dump it in the garden, after all it's just a very pure form of dirt.

With that FE content, it should make a decent fertiliser for your grass - well diluted, of course.

Proceed at your own risk, I accept no responsibility if it goes pear-shaped.......

 

[droopsnoot]

That Rapid looks like a nice bit of kit. Should be good for running the vat.

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'll have a go over the next few days, though my citric acid has now turned up - after admitting they'd lost the parcel and advising me to contact the seller for a replacement, they've now found and delivered it.

 

[Maker]

I am assuming it must be magnetite which will oxidise back to "proper" rust. The powder is magnetic when dry and I am tempted to dry it out and find a use for it.

Any ideas? Pretty sure it's ok to dump it in the garden, after all it's just a very pure form of dirt.

S.

I just googled it and found no workshop/home uses but apparently it reduces hexavalent to trivalent chromium which is incorporated into the magnetite when it crystallises, so maybe stainless electrodes aren't that bad after all.

I would just dump it in the garden. The bush in out front garden outside the garage hasn't died yet, uprising considering I feed it all my electrolysis and caustic soda sludge, dirty ferric chloride, DCM & other tasty solvents.

 

[MattF]

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'll have a go over the next few days, though my citric acid has now turned up - after admitting they'd lost the parcel and advising me to contact the seller for a replacement, they've now found and delivered it.

Simple things can totally cock the process up. That's where having an ammeter on the setup comes in handy. If you don't see any current draw, you know either a connection is poor else something else is up. Most problems, if the setup is generally sound, are usually down to bad connections.

 

[slim_boy_fat]

Would 15 amps from a PSU be too high an output for running my tank/bucket?

Watching a unit on the 'Bay with this output, to avoid any risk of b*ggering up my Ring battery charger/starter.

 

[bigegg]

Would 15 amps from a PSU be too high an output for running my tank/bucket?

Watching a unit on the 'Bay with this output, to avoid any risk of b*ggering up my Ring battery charger/starter.

the actual amperage depends upon the resistance of the tank, and the voltage.
15a might be max, but you shouldn't ever exceed a couple of amps.
might be worth putting a 3a autofuse in the line, just incase you ever short out the supply tho...

 

[Robotstar5]

Would industrial 24VDC power supplies be any good?, I've got a few from 1A up to 10A output.

 

[Screwdriver]

Yes all you need is about 10 to 15 volts and your setup will determine the amount of current flow. The only thing the power supply needs to do is to be able to supply a constant current (1-2 A is plenty) for up to a couple of days at a time.

 

[Robotstar5]

Yes all you need is about 10 to 15 volts and your setup will determine the amount of current flow. The only thing the power supply needs to do is to be able to supply a constant current (1-2 A is plenty) for up to a couple of days at a time.

Shouldn't be a problem, I've seen this type powered up for 10+ years!

 

[Screwdriver]

Cool. I assume you can turn the voltage down or you might end up running too much current. Either that or use a dilute electrolyte. Seriously, unless you want to blast something clean and are not fussy about the surface finish, you only need 1 A really to make it work.

 

[Robotstar5]

Cool. I assume you can turn the voltage down or you might end up running too much current.

That's why I asked as the voltage is generally only adjustable from 26-30V so I would have to dilute electrolyte more than a 12V system?

 

[Screwdriver]

Specifying a current without a surface area doesn't make sense, just saying a blanket 1A total doesn't cover everything...

What you need is a certain amount of mA per square cm of surface - more surface = more current to have the same effect in the same time.

1A treating a car chassis will take a year - 1A doing a hammer head will take a couple of days...

Run a high voltage if you want, put a resistor in series to drop it.

Also remember, current is drawn, not pushed.

Sorry but you are just being pedantic. I am trying to help here, not score points. I don't feel the need to write a dissertation on the subject and if someone on here was even considering doing a chassis, I am pretty sure they would mention that. Don't you think?

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.

There are a few simple practical guidelines and rules of thumb which will give the lay user fantastic results. There's no need to start performing calculations or trying to make it sound more complicated than it actually is.

 

[slim_boy_fat]

Didn't mean to start a war, lads.

I've spotted another one outputting 5 amps which I might have a punt on. This should do the trick, I hope?

http://www.ebay.co.uk/itm/281956497129?_trksid=p2055119.m1438.l2649&ssPageName=STRK:MEBIDX:IT

 

[slim_boy_fat]

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