Rust removal - will there be anything left?

[tolsen]

Following Evilution's advice and I am now trying rust removal by electrolysis.

100 litres of pure Royal Deeside water mixed with 500 grams of soda crystals. Iron pinch bar used as anode. Old 20 amps non intelligent battery charger is power source. Current at the moment is 4 amps.

[markinnz]

Nice .. how long is the process expected to take ? It'll lift off the remaining paint as well wouldn't it ? (bit a of a bonus if it does :-)

[tolsen]

We'll find out over time. Factors such as bath temperature, solution strength, current, rust thickness etc I assume will affect required treatment time. I've just inspected right hand side of engine subframe after brewing for 9 hours. Most rust just fell off and remaining rust came off with a washing up brush. Will be treating left hand side for 4 1/2 hours and can then compare the two sides. Looks like I need to source a large drum so I can treat the whole subframe in one go.

[tolsen]

A great success thanks to Evilution.

View of the underside of a rather rusty 450 Cabrio subframe now partly cleaned by electrolysis:

The tide marks are plainly visible. I will need a tub style tank to treat the forward transverse part. Using our bathtub is not an option, although quite tempting.
Both side were treated for 9 hours, then pressure washed.

[Thrumbleux]

[
. I will need a tub style tank to treat the forward transverse part. Using our bathtub is not an option, although quite tempting.

.

Plenty bathtubs in the corners of fields around Banchory that cattle aren't currently drinking from. Get lucky with a live electric fence and you have a power source too!

Presumably the receptacle has to be non-metaillic - ruling out slitting a 40 gallon drum lengthways?

[heinkeljb]

Get a 45 gallon plastic drum and slit it length ways! Or for even more depth, stop it from rolling and cut a slot in the side just wide enough for the sub frame section to go through.

John

[tolsen]

A pig trough dug in the back yard lined with polythene ought to do the job.

[Evilution]

That's not a bad result for only 9 hours, I always go for a straight 24. It will only remove rust, it won't lift old paint so if you have rust under the paint, you'll have to wire brush those areas first. I like the idea of the plastic 45 gallon drum with a window cut in the side.

[markinnz]

I'm so glad they don't use salt on the roads around here .. means my turbo'd roller-skate will last longer! :-)

[pistanbroke]

Any of you ever used molasses solution. first came across this last year on Austin A35 club forum, from a guy in Australia. Mix 5 litres molasses (available from equine suppliers as a horse feed supplement), with 25 litres water and leave your rusty components soaking. Amazing results though it does take longer than 9 hrs to achieve those results shown above.

[tolsen]

Molasses for rust removal is rather messy and time consuming. Less suited for our Smart cars unless you possess a second car or a bus pass.

[cougar7609]

The idea of the bathtub brings back memories of my grandad who would use anything and everything to get the job done, half of the time my grandmother never noticed until she went looking for some kitchen implement and couldnt find it because he had used it as a screwdriver or to pull apart something. lol

Could you not get away with it while the other half is at work?

Looking good though, Ive just taken the front brace (bit under the radiator for those who know the van) off a Citroen Relay van that was in that state, I found it easier to sand it down and repaint with rust killing paint. Its worked very well. I have to say it would probably be quicker easier and cleaner doing that than using baths and the such, but then again it may not be as good but it does the job on an old van for me

[mottofreee]

You can also use a metal container but must be small changes made.
Surface that comes in contact with the electrolyte is painted (90%) with electrolyte-resistant paint(I have used it : http://www.magazinvopseaauto.ro/spra...negru-mat.html ) ;
The current is proportional to the unpainted surface electrode;
pieces to be suspended in the electrolyte (do not touch the vessel walls).
For large parts, we used different containers:
- From the cans of plain water (20l) to oil barrel (208l) 1-DSCF1432.JPG

Unfortunately, the container should be cleaned after each use well - perhaps blasting is the most appropriate method + repainting.

[tolsen]

Taking delivery of a 205 litre plastic drum tomorrow. Intend to cut drum in half just as shown in previous post. The drum is a wee bit too short but I assume the ends will flex sufficiently to allow subframe to fit.

[Evilution]

Come to think of it, a child's inflatable paddling pool probably would have been a better idea. You could do the whole thing in 1 go and it doesn't take up any room when not in use. May have been cheaper too.