question removal of rust

[me_groovy]

hi all, got some pipework I'd like to keep original if I can. rust has gotten this far. so far I've taken a brillo pad to it to knock off the worst but what's the best approach to removing it without removing the metal underneath?

 

Thanks

[cosrec]

electrolysis

[MB1944]

I second that, I have just started using it. Amazing.

[Niels v]

Or if you have time molasses

[AmmoMan]

I second that, I have just started using it. Amazing.

 

I third it, also just started and can't believe how easy/cheap it is with excellent results.

[Hoseman]

Molasses, cheap

[MB1944]

Not cheaper than washing soda, water and a battery charger which most should have.

[Surveyor]

Not cheaper than washing soda, water and a battery charger which most should have.

 

I tried and didn't do well, can any one post method a quantity

[Hoseman]

I tried and didn't do well, can any one post method a quantity

Molasses,plastic tub,warm water!

Nothing simpler.

[Pete Ashby]

electrolysis

 

electrolysis works very well, particularly on small parts that may be damaged by more aggressive methods. There are just a few points that need to be addressed for the process to be effective. There are any number of web sites giving the details but basically it boils down to:

 

a: make sure the sacrificial steel is in line and reasonably close to the work piece but NOT touching and do not use this

process on Brass, Copper or Aluminium

 

b: scrub the work piece with plenty of clean water immediately it's removed from the electrolysis bath

 

c: dry the work piece quickly ( I use a hot air gun to get into the corners etc)

 

d: undercoat with a good quality primer

 

Pete

[Niels v]

And ventilate during the electrolysis process, hydrogen gas forms during the process.

And don't use electolysis for high strength steel

[Surveyor]

Molasses,plastic tub,warm water!

Nothing simpler.

 

Haven't heard of this method, what volume of water and how much molasses?

[Pete Ashby]

And ventilate during the electrolysis process, hydrogen gas forms during the process.

And don't use electolysis for high strength steel

 

Good point Niels

I should have said that, there is a fair volume of Hydrogen produced it's best to do it in a loose covered plastic tub or barrel outside, certainly not in an enclosed space.

 

Pete

[Whittingham warrior]

Haven't heard of this method, what volume of water and how much molasses?

I've seen it at a ratio of 10 parts of water to one of molasses. After the first week scoop off the scum that has formed.

[Zero-Five-Two]

Had a go at the electrolysis a few years back, took a bit of trial and error to get it right but the results were superb, and it has become a staple of de-rusting Militant parts ever since. Stuff can be left to de-rust while you do something else.

 

 

Dustbin of soda in action, you can tell how well it is working by the amount of scum

 

Couple of tips I found to improve performance.

 

Make sure the sacrificial steel in reasonably clean to start with, that bit of rusty old angle iron you found at the back of the shed just wont cut it. Also try to make it a similar size to the item being cleaned, too small and it wont lift the rust off, too bit and it will just draw current from your charger.

 

Keep the charger clips out of the soda solution, they will dissolve faster than the rust. Give the solution a stir every now and again. Mostly I leave an item "in" for 24 hours, and turn it/stir it up every 8. Works for me.

[AmmoMan]

Have a before/after photo of a Bren T&E that I tried my first electrolysis session on.

4 hours in a bucket with a battery charger, big spoon of soda and an old iron bar.

WD40 once it was dried off.

 

[me_groovy]

this is brilliant, thanks guys. I've been checking some youtube videos today of DIY setups and I'll give this a go for sure

[cosrec]

What i like about it is you cannot overdo it eg once the rust has gone nothing happens. If you end end up with holes in your pipes they where shot anyway

[john1950]

Very important to ventilate the area and No naked Flames nearby.

[ruxy]

Have a before/after photo of a Bren T&E that I tried my first electrolysis session on.

4 hours in a bucket with a battery charger, big spoon of soda and an old iron bar.

WD40 once it was dried off.

 

 

A nice valuble assemby , however because of the value - I would have tried something far less aggressive first - such as a soak in white vinegar , this would have given exact same results - so electrolysis not a good fair test. It seems to me the original treatment was in part still extant - and seems to have stood up during the electrolysis (as expected).

 

Some of the components - knurled wheel & levers seem 'hot black oxide' finished (blackadizing) - esp. on a knurled surface this gived very good protection long term. The appearance of light rusting can sit on the surface without penetrating. In fact fresh from the wash tank , it can seem to have red rust contamination.

I worked at a factory that did this process and similar finishes in-house - such as 'gun-bluing' . A smelly Dept. so I used to keep out - however first class for getting your own 'govvy' jobs done. Should have taken more notice of the process , after the wash tank - I think came a final dip in 'contact inhibitor oil' , that soaked in to the oxide..

[bigduke6]

Electrolysis is the way to go, as long as you clean the item and the anodes every few hours etc the results are excellent, I do mine outside, and in most cases leave overnight. You can achieve better results by placing several anodes around the item.

 

For small items I use Unitor Metal Brite, this is Phosphoric acid based.