Rust Removal using Electrolysis on a large scale

[TOBASH]

What is the advantage of this over acid bath?

Most of the parts I have that are rusted get an acid bath, a wash, a blast with WD40, and a trip to the oven to get rid of latent water and theoretical hydrogen in the steel.

What is the advantage of this over muriatic (plumber's)acid given most of the rust in the washing soda method is just converted to another type of rust and not usable metal?

 

[Coolerman]

Well first, it's a lot safer than a big vat of acid. Especially if you have pets or kids.

Second, no method of rust removal converts rust to 'usable metal'.

Third, it's cheaper. Water = free, a container of sodium carbonate that will last you years = #8.00 around here, a 33 gallon plastic trash can from Wal-Mart = $7.99, and most folks have a battery charger and a bunch of scrap steel laying around if they own a Cruiser.

The acid works great though. I have done many nuts and bolts in muratic to quickly clean them...

 

[TOBASH]

Fair enough coolerman

Muriatic is cheap as dirt, but it is dangerous, especially to inhale.

Thanks, and best,

T

 

[einstein]

How long are you guys leaving your parts in? Can you leave the parts in for to long and cause damage, or does it automatically stop fuzzing when its done?


Matt

 

[2fpower]

So I had an idea for a good vessel to do this. something on the lines of coolermans. How about taking an old keg? Stainless steel - really thick. pick them up for about $40. Seems perfect. Just cut the top off.

Thoughts?

Also, I found the soap at Ace hardware store. Actually they did not stock it but they ordered it into the store from ACE and it cost the same as on the website with no shipping charges.

 

[einstein]

You dont want to use stainless period. Its toxic if it grounds out it releases a toxic gas.

Even better use your garbage can or your recyclable container.

 

[2fpower]

Thanks Einstein. I had not done the research yet. I tried to delete my posting, but could not edit it.

 

[aktundra]

Came accross this technic after I had finished my 40, so I have tried nothing and have no experience, so take this idea as completely untried.

But I thought a children's wading pool ( hard plastic not infatable) may be a cheep tub for larger parts ( bibs, doors, etc)

 

[einstein]

That actually is a excellent idea. I think either a wading pool or my recycling garbage bin that the city makes me have is going to be the next one. Thing i like about the wading bind is its long you can set alot of parts in it and make sure its not grounding out, plus cleaning the rebar would help also.

 

[sggoat]

Just found this thread----Hydrogen embrittlement will only occur at elevated temps(>1000 deg F), and over a long period of time(>12 months). Also depends on the austentitic properties of the steel-usually higher carbon steels with some level of Chrome in them.(usually found in T-11 through T-21 steels)--not sure, but don't think cruisers were fabed of this.

 

[Midgainc]

You guys will laugh at this one....but...I actually used molasses to remove the rust on a milk can a couple years ago. I put the milk can in a 55 gal drum with a concrete block on top, then filled with water and 50 lbs of agricultural molasses. 7 days later, 95 % of the rust was gone....unfortunately I had to waste all that good mash when it was over. Call me crazy, but I heard this would work, and I just had to test it.

 

[tucker74]

I've used electrolytic rust removal quite extensively on everything from small parts to bell housings and even brake drums. I've never seen any issues, the drums turned fine after de-rusting and painting (would have seen issues here if brittleness was a problem). I used a pretty standard setup, cooler, 16mm sheet metal electrode, super baking soda and a bolt or wire to hang said part. This works much faster than molasses and doesn't remove as much material as blasting (though I use soda and media blasting as well). Hope this helps -



Tucker

 

[toomanytoyzz]

You guys will laugh at this one....but...I actually used molasses to remove the rust on a milk can a couple years ago. I put the milk can in a 55 gal drum with a concrete block on top, then filled with water and 50 lbs of agricultural molasses. 7 days later, 95 % of the rust was gone....unfortunately I had to waste all that good mash when it was over. Call me crazy, but I heard this would work, and I just had to test it.

I use this method all the time. To me, it's better than electrolysis. It's much easier to set up, and you can leave it alone without wondering if the shop/garage is on fire for leaving the electric on. The one thing electrolysis has over molasses is it gets the job done much faster. I'm almost at a year with my resto so time is something I'm willing to sacrifice on derusting parts.

 

[PyroNeuby]

I've been using the electrolysis method for a while myself, currently working on the bib and grill for my '76 FJ40 using an old 30 gallon plastic storage tub and a NAPA 85-200 Manual Trickle Charger. I'm having to do approx. half at a time due to size and using an old brake rotor for the anode. If you get a small trickle charger like this you'll likely have to bore holes in the plastic chasing like I did as they have a thermal cycling breaker in them. I used a 3/8" bore bit making 2 holes per side and just keep a fan pointed in the direciton of the charger while using it.

Here's a close up on the bottom of my bib where the hinge mounts showing a good before/after example. (I did use a spot weld cutter to remove the reinforcement first.

Once finished a plan on using a quick acid wash to pickle the steel (yes I know I could have used this from the start, but electrolysis does in fact deposit some good iron back into the pits where acid wash does not, also this should be a much easier wash using less diluted muratic acid afterwards). Once the black oxide is removed from the wash I'm going to try electrogalvanizing to eliminate the possibility of future rust.

I'd like to find a old plastic animal dip tub to use, also a 55-gal plastic drum (most tent rental places have them to fill with water and anchor tents) would work for larger parts. The other thread on using an old PC power supply sounds interesting.

 

[Splangy]

Just found this thread----Hydrogen embrittlement will only occur at elevated temps(>1000 deg F), and over a long period of time(>12 months). Also depends on the austentitic properties of the steel-usually higher carbon steels with some level of Chrome in them.(usually found in T-11 through T-21 steels)--not sure, but don't think cruisers were fabed of this.

Not exactly true. Hydrogen embrittlement can occur at low temps and hardened fasteners are susceptible to it. That includes the hardened class 10.9 fasteners found on Land Cruisers.

That said, I have no idea whether or not this process will create the hydrogen concentration necesary for embrittlement to occur. I doubt you would have to worry about much, but I wouldn't toss any head bolts in the mix.

 

[PyroNeuby]

Anyone used Super Iron-Out to remove the black magnetite after electrolysis bath? Also in electroplating use of an aggitator in the solution as well as increase temperature help prevent buildup on the anode and increase effeciency. Anyone tried this? I'm thinking an immerision heater grounded to the cathode (your part being de-rusted) and a plastic fish aerator might really help.

I'm getting ready to attempt zinc electroplating after all the rust is stripped. Just waiting on chems from Amazon and brushing up on my electrochemistry. (Been a while since college, I'll keep you posted.)

Oh I found a good science journal report on embrittlement the other day, I'll post the link soon.