Thread: Well, that went well, not!

Ken

Not being a chemist, I cannot answer your question. But there isn't any reason to mix them together , using caustic alone will remove both paint and rust. So why would you mix the washing soda in ?

The rust will turn black, you can then brush it off with a wire brush .

I have read about the embrittlement thing, but it has never happened to me .

Mike

Hi Morrisman,

I'm not a chemist's bootlace either, so it sounds that caustic soda can be used alone. I presume that what ever chemical is added to the water, it acts as an agent to aid in the conductivity of electricity. I plead dumb your honour, someone will have the answer.

Ken

Took the plunge and tipped in some caustic soda with immediate results.

The amp meter jumped from 3 amps to off the scale, and shut down. The Arlec is dual voltage, 6 and 12 volts, so switched it onto 6 volts and tried again.

Things are bubbling away again on 6v with a current draw of 4 amps.

The lathe bed feet were originally Hercus green, and have been over painted in sky blue by students. Reckon they applied the paint with a mop.

The blue has all come off in sheets, and now the green is loosening.

Ken

link

ELECTROLYTIC RUST REMOVAL (ELECTROLYSIS)

The electrolytic process finally took 99% of the paint off including the factory paint underneath. I'm surprised that the inside of the castings were not given a lick of undercoat.

In fact, there was no sign of undercoat on any of the castings.

A final lick with a wire brush in the angle grinder, and the feet are as good as new cast.

There's a tiny bit of rust on the inside, but some undercoat will fix that.

I might try and get some undercoat on today, if the wind drops.

Sorry about the crappy snaps, iPhone cameras are next to useless, so is the photographer.

Ken

Wow. They came up neat. I may have to consider electrolysis next time i need to get some crap off any castings. What did you end up using? A caustic soda/washing soda combo? 50:50 mix?

Simon

They look real good, as you say like new castings.

One question though, will the electrolysis remove oil/grease as well, or just rust and paint?

I'm not sure if electrolysis will remove grease, but I'd reckon with a 50/50 mix of washing soda and caustic soda, nothing would survive.

Still, I would chuck the part in a tub of kero, and hit it with a brush. I think the cleaner the part, the faster the process will be.

Now got some etch primer on. I'm using White Knight Rust Guard S.L.S. Etch primer, grey. A bit over $10 at Bunnings.

More shock, horror, gasp. My tin of Dulux enamel top coat has gone hard, and to make matters worse, the sticker on the can with the Hercus green formula on it, has totally faded, unreadable, zilch, jack sh*t..

Guess I'll have to take a painted part in to the paint supplier and have it colour matched.

Question. Will any paint mob custom mix a colour and put it in a spray can?

Ken

Hi Ken,
All depends on how fussy you are going to be about the colour match but Killrust Wilderness (a Colourbond colour) is a pretty close match to the Hercus green.
Give any of the Dulux spray paint you get from the green shed a big miss, its fast drying but chips if you look at it mean and disolves with the breifest exposure to petrol etc.
Killrust takes a while to dry but it gives a very durable finish and I think the white Knight metal paint is pretty good too.
Killrust is cheaper at the big blue shed than White Knight at the big green shed.
Cheers,
Greg.

Originally Posted by neksmerj

The electrolytic process finally took 99% of the paint off including the factory paint underneath. I'm surprised that the inside of the castings were not given a lick of undercoat.

In fact, there was no sign of undercoat on any of the castings.

A final lick with a wire brush in the angle grinder, and the feet are as good as new cast.

There's a tiny bit of rust on the inside, but some undercoat will fix that.

I might try and get some undercoat on today, if the wind drops.

Sorry about the crappy snaps, iPhone cameras are next to useless, so is the photographer.

Ken

HI Ken,
reckon I'm going to have to try that method. I have always used molasses and water, smells nice but messy.
Is your Iphone in a cover as I found the flash is distorted with the cover on. I now slide the lens and flash just clear and take the shots.

Phil

I find a 50:50 mix of turps and meths is very good for stripping paint.

Michael

Struth, I can't take a trick. I went to Bunnings to buy a new tin of Dulux Quit Rust epoxy enamel, Green Freeze, and guess what, they no longer stock it. It was the closest colour I could find to match the Hercus green.

They directed me to a nearby Dulux Trade Centre, and got the same story, "sorry, it's been discontinued". Bugger me.

At best, if I take a painted sample in, they will try and match it in an industrial paint. Won't be quit rust, & won't be epoxy based.

This will teach me for being slack in the restoration process.

Ken

Go for the Wattyl Kilrust. I have it on all my machines that have needed painting and works a treat

Michael

Gentlemen, thanks for all the comments re Hercus green paint. I want to stick to the paint I started with, but it looks like I have to use a normal Dulux enamel or industrial enamel.

I sent am email to Dulux expressing my desire to continue with the Quit Rust Epoxy enamel, but have been informed that this type of paint was discontinued in 2009.

Is colour matching done by eye, or do paint centres have a computer matching system?

I still have 1/3 of a litre of the original paint left, but it's covered with a thick skin. Can I recover this paint, and how? I will be applying the paint with an air brush.

Ken