Is there such a thing as too many amps (30a) when doing rust removal electrolysis or will it just be faster?

nadiayorc

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I bought a 12 Volt 30 Amp power supply yesterday from Amazon (arriving in a few days) and some appropriate gauge cables (10AWG, max 50 amps according to the amazon page) and some 1cm diameter carbon rod eletrodes and I didn't really consider if it could be too many amps for rust removal. Everyone else I see doing it seems to use 12v with around 2-10 amps, normally from a car battery charger. I wanted to use a proper power supply as car chargers can be awkward to find without the smart features these days, and often aren't that consistent in their output.

As far as I understand, the amperage is how many electrons are output through the wire? Would there be any negative effects of the higher amperage or would it just be faster?

I would appreciate any responses that aren't just guessing and from people that have tried higher amperages or know the physics behind it.
 
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I use an adjustable DC power supply for my setup and have run anywhere between 2 and 15 amps when trying to clean up my iron pieces. The only thing I noticed when running the higher amps is that it seems to break down the wrought iron pieces faster. It does clean rust faster, but (and this is a hypothesis) I feel like the the higher current flow starts to break down the wrought iron layers. Now there could have been rust in those layers/graining of the iron, but my pieces on higher amps did have some stronger pitting compared to those on a 2 amp current. Also if you think about arcing electricity off of something, a strong current will burn the item, a weak one is just a spark. When I run my tank now, I just keep a close eye on everything no matter what I amp setting I run and may even pull things several times to scrub them up and check them. Best practice will be to find some junk iron in the field and play with it.
 
I use an adjustable DC power supply for my setup and have run anywhere between 2 and 15 amps when trying to clean up my iron pieces. The only thing I noticed when running the higher amps is that it seems to break down the wrought iron pieces faster. It does clean rust faster, but (and this is a hypothesis) I feel like the the higher current flow starts to break down the wrought iron layers. Now there could have been rust in those layers/graining of the iron, but my pieces on higher amps did have some stronger pitting compared to those on a 2 amp current. Also if you think about arcing electricity off of something, a strong current will burn the item, a weak one is just a spark. When I run my tank now, I just keep a close eye on everything no matter what I amp setting I run and may even pull things several times to scrub them up and check them. Best practice will be to find some junk iron in the field and play with it.

Yeah I guess the best thing to do is just mess about with scrap when it arrives. I've dug up plenty already such as nails and stuff. It won't be here for a while though, estimated delivery is next Wednesday so just wondering about other peoples experience.
 
As far as I understand, the amperage is how many electrons are output through the wire? Would there be any negative effects of the higher amperage or would it just be faster?

In my experience, it is faster, but it can also unnecessarily pit the item.
 
In my experience, it is faster, but it can also unnecessarily pit the item.

I guess I just have to try it out and see, I should really have got an adjustable one but oh well. It was only £15 and has quite good reviews.

Might try a larger amount of water/more gap between the item and electrode for a bit more resistance, but the graphite electrodes I got are only 10cm long and 1cm diameter so not really suited to very deep buckets or something.
 
......but the graphite electrodes I got are only 10cm long and 1cm diameter so not really suited to very deep buckets or something.

for my tank I use 1ft sections of pre-cut rebar from Home Depot. At $1.65 each, I use them until they rust over and then toss them. I can tell from your use of cm and £ you're probably not in the US, but I am sure you local hardware or building supply store has them.

https://www.homedepot.com/p/Weyerhaeuser-1-2-in-x-1-ft-4-Rebar-05150/202094322
 
for my tank I use 1ft sections of pre-cut rebar from Home Depot. At $1.65 each, I use them until they rust over and then toss them. I can tell from your use of cm and £ you're probably not in the US, but I am sure you local hardware or building supply store has them.

https://www.homedepot.com/p/Weyerhaeuser-1-2-in-x-1-ft-4-Rebar-05150/202094322

The pre cut rebar is also what I use. I just rotate them and scrape them clean occassionally. My power is just a simple old wall wart ac to dc power supply. Can't remember the specs, but I had a box full of them and picked one that matched what people were recommending online. I think it was 1 amp. I cut the ends, soldered in a 2 amp fuse on one side, and then soldered on clips. It has had no problem doing horseshoes and door hardware in a 5 gallon bucket, but it takes a few days. I keep the object a few inches away from the rebar.
 
So you guys aren't using typical car-battery chargers? I need to research this!
 
Well one thing you need to understand:
1- Current (Amps) is DRAW by the circuit.
2- Voltage is supplied by the source.

So a 12V, 30A source will apply 12V to the electrolysis electrodes.
How much current is drawn depends on the resistance of the electrodes and solution. This depends on the size (surface area) of the electrode (item being de-rusted counts) and the type and amount of 'salts' in the solution as well as the distance between the part and electrode.

You could use this on smallish parts and electrodes and draw only 1 Amp. This means (by Ohm's Law, that the resistance is E/I = 12V/1A = 12 Ohm. No problem.
For larger part/electrode current draw may go up to a few Amps.

The biggest issue is if the part and electrode touch then the resistance can be close to Zero Ohms. This will try to pull near infinite current from the source.
Hopefully the power supply has internal current limiting or shut down on a short condition.

Did you go to the Sticky post at the top of this sub-forum and read through the electrolysis section of the linked paper??????
This has much of the fine details.
 
Well one thing you need to understand:
1- Current (Amps) is DRAW by the circuit.
2- Voltage is supplied by the source.

So a 12V, 30A source will apply 12V to the electrolysis electrodes.
How much current is drawn depends on the resistance of the electrodes and solution. This depends on the size (surface area) of the electrode (item being de-rusted counts) and the type and amount of 'salts' in the solution as well as the distance between the part and electrode.

You could use this on smallish parts and electrodes and draw only 1 Amp. This means (by Ohm's Law, that the resistance is E/I = 12V/1A = 12 Ohm. No problem.
For larger part/electrode current draw may go up to a few Amps.

The biggest issue is if the part and electrode touch then the resistance can be close to Zero Ohms. This will try to pull near infinite current from the source.
Hopefully the power supply has internal current limiting or shut down on a short condition.

Did you go to the Sticky post at the top of this sub-forum and read through the electrolysis section of the linked paper??????
This has much of the fine details.

I did have a feeling this was how it worked but wasn't quite sure.

After I posted the first post I did find this very useful (and long) guide that I read through and learned a lot from.

I don't think the power supply has any short circuit protecting as it was just a cheap chinese one but it has pretty good reviews generally. I will just have to be careful not to let them touch.
 
So you guys aren't using typical car-battery chargers? I need to research this!

The 1 amp ac to dc wall wart power supply did the job in my link below. About day or so on each side. I did some additional detailing and scrubbing, but the electrologists caused the major rust to just flake off. Unless you're in a big hurry, that's more than enough power for coins, small tools, horseshoes, etc...

https://metaldetectingforum.com/showthread.php?t=269707
 
This is a link to the one I bought. It's a DC power supply, and the upside is you can adjust the voltage and amps along with it. Little more pricey, but you can control it and know what settings you're on. The only thing I added to it, was extra lengths of wire with larger clips on them. So I go from the device, to the wires that come with it, to an extra length of wire with a larger clip. That way, when the clips rust, I can toss them and add new ones.

https://www.amazon.com/gp/product/B073TW8H2S/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

On a side note, to avoid flipping items around in the tank for coverage, I will often suspend my items in a steel painters bucket and that bucket becomes my electrode instead of a piece of rebar. It helps things along a lot faster. Just put the metal bucket in a plastic one, because after a while it will develop some tiny holes.
 
I did have a feeling this was how it worked but wasn't quite sure.

After I posted the first post I did find this very useful (and long) guide that I read through and learned a lot from.

I don't think the power supply has any short circuit protecting as it was just a cheap chinese one but it has pretty good reviews generally. I will just have to be careful not to let them touch.

That is a good paper on the practicalities of doing electrolysis.

If your 30Amp PS has no short protection it would be a very good idea to add a fuze inline with one lead. A 10-25Amp automotive fuze is easy to use. Just install spade lug sockets on the wires to change the fuze.

Does that PS have an Ammeter?

The 1 amp ac to dc wall wart power supply did the job in my link below. About day or so on each side. I did some additional detailing and scrubbing, but the electrologists caused the major rust to just flake off. Unless you're in a big hurry, that's more than enough power for coins, small tools, horseshoes, etc...

https://metaldetectingforum.com/showthread.php?t=269707

That is what I use: a 12VDC, 1A wall wart.

I insert a 1Ohm resistor in series to measure the current (Vdrop across R) with a DVM. Being able to monitor the current is important.

I have used iron/steel electrodes but these need cleaning often.
Just bought some carbon electrodes but haven't had a chance to use them yet.
 
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