Electrolysis

sauter shop
shop deals on amazon
Shop deals on ebay
UKworkshop.co.uk

Help Support UKworkshop.co.uk:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
C

Charlotte

Established Member
Joined
16 Jan 2009
Messages
69
Reaction score
0
Location
Kingston, London/Gloucestershire
So I bought some new (old) toys and they are a bit rusty.

Currently, I have a cap iron and blade hooked up to the -ve side of a battery charger. The anode is an old circular saw blade (homebase special so no carbide in sight). Both are positioned with wood and cable ties in a plastic box with about 7-10 ltrs of water and 5 tablespoons of sodium bicarbonate as electrolyte.

I'm not seeing bubbles and the rust is still there.

I'm all ears as to why! Connections are obviously solid. Current is 6v trickle - the onboard ammeter reads about 1.2.
 
Charlotte,

Possible reasons are that your trickle charger isn't big and powerful enough - I'd expect to see 5 or 6 amps when dong this on my 12v charger.

the electrodes are too far apart - try them closer but not touching

The saw blade is stainless steel - unlikely but try to find a scrap of ordinary iron or steel (nails?) to se instead.

You could always try the citric acid approach instead, or phosphoric acid - they both appear to work.
 
Charlotte,

I suggest you would be much better off using one of the Shield Technology products. These really do work very well and are available from Workshop Heaven.

Jim
 
yetloh":3t8z438g said:
Charlotte,

I suggest you would be much better off using one of the Shield Technology products. These really do work very well and are available from Workshop Heaven.

Jim
Click to expand...

Yep, what he said. :wink:
 
Hi Charlotte,

I use electrolisis to great effect, first thing is try using Sodium Carbonate (available for a couple of quid from most supermarkets as washing soda). I recall that bicarb is not as good.
You have things wired up the right way round (believe me I've got it wrong many times).
As others have said try getting things a bit closer but not touching and up the amps if you can. Either that or leave it for a while, nice and slow is usually best anyway.
Regards

James
 
Hi Charlotte,
I have used this technique several times , and agree with James that you do indeed have it wired up correctly (anode on the +ve, part/s to be derustified on the -ve ) and hes right with bicarb is NOT what you should be using, sodium carbonate (washing soda) is what I usually use at a couple of quid a kilo bag from your local s/market.
my "formula" is about a 1/4 bag in a 25ltr bin topped up with water to a couple of inches of the rim ( for plane bodies) and ancilliaries afterwards, seems to work a treat for me.
another tip, if doing plane bodies towel dry them after their dip and stick them in a warm NOT HOT oven, as the porousity of cast iron holds moisture and the baking dries them out substantially better than just towel drying.

edit: 15-20 mins in the oven , and you should be able to hold them in your hand when they emerge (hence it only needs to be WARM NOT HOT DAMHINT :oops: )
HTH
 
I tried this with a car battery charger and a bucket of Soda. It turns out that my car charger is too intelligent and cuts out if there is not enough resistance across the electrodes...
 
Surely the electrolyte doesn't matter as long as there is enough conductivity and there are no reactive ions in the solution.

Amperage is a measure of the flow of charge - the more the better - but you need to know how much is actually flowing. Put a meter in series to measure it - be careful though, don't blow your meter!!!

As for the sacrificial anode, this must be iron or a metal with a higher electrode potential (absolutely not copper!). I'd be careful about alloys, etc. they may have undesirable "impurities" - pure iron sounds good.
 
From the link that BugBear posted (I've read it before, but you saved me going looking for it :) )

"although the chromium present in stainless steel may produce poisonous chromium compounds in the electrolyte as it erodes which are considered dangerous and which will be illegal to dispose of down the drain in many areas"
 
I switched out the blade for an iron bar and put everything in a smaller container to no avail. I think the charger is all clever and designed to be above bucket chemistry but have one final plan before caving and taking Matthew up on his offer!
 
Charlotte":1r5ikmmf said:
I switched out the blade for an iron bar and put everything in a smaller container to no avail. I think the charger is all clever and designed to be above bucket chemistry but have one final plan before caving and taking Matthew up on his offer!
Click to expand...

Charlotte

Find yourself a dairy supplies firm and get 5L of Milkstone cleaner (about 50-60% phosphoric acid) works a treat when diluted down to about 15%. It just dissolves rust out.

There's bound to be loads in\around Gloucestershire. Costs < £10.

I've used it extensively on cleaning up car parts that make LN stuff seem like it comes from a Pound shop. :wink:

Dibs
 
I bought my Milkstone Remover from SCATS - they have branches over the South.
It works a treat and the 5L will last for years!

Rod
 
Rod
What exactly do you do with this stuff from Scats?
I have several 'rust chunks' that might benefit from this and was going to try the electroysis route but this may be easier.
Hope your trip to Canada was fun!
Cheers,
Martin
 
mahking51":1x5ejasr said:
Rod
What exactly do you do with this stuff from Scats?
I have several 'rust chunks' that might benefit from this and was going to try the electroysis route but this may be easier.
Hope your trip to Canada was fun!
Cheers,
Martin
Click to expand...

Milkstone Removes is Phosphoric Acid at somewhere near 50-60% concentration.

Dilute it down to around 15% and either dip the metal in it and leave it there for say 5 mins and then pull it out and check or spray it one and "top up" a little later.

http://www.42gpw.com/acid.html

might give you an idea of what\how long\etc.

It's certainly one of the cheapest and possibly quickest options going - not to mention due to thea acid's tendency to attck iron very slowly - possibly a very safe one (from the perpective of minimising the affect on good metal).
 
Martin

It is a cheap way of buying Phosphoric Acid. ( I read about it a few years ago on a Car Forum)

I dilute it with water about 50% in a bucket and immerse the rusty parts overnight.
Rinse in water and clean off the black/grey film with wet & dry etc. Any rust left in pits/holes etc has been chemically "pickled" and the resultant black compound can provide some corrosion resistance.

Canada was great - mainly dry and sunny but getting colder. It was mainly to see the Grandchildren so did not do much touring around. Managed a couple of walks to LV for some small items!

Rod
 
Benchwayze":3dvzwdp5 said:
Charlotte":3dvzwdp5 said:
But they cost money whereas electrolysis gear I have kicking around!
Click to expand...
Powerful argument!
Click to expand...

The last time I bought the stuff it cost me £7 for 5L's - at some point it's just not worth faffing about and if the car restoration people are using it - you
can bet it works a treat.

But horses for courses and that.
 

Latest posts

Back
Top