rust removal

[Dougie SwanParticipant @dougieswan43463]

Hi

can anybody tell me if there are any chemicals available to remove heavy rust from iron and steel?

I am begining the restoration of a very old and rusty Aster engine and wondered if the pickle solution I use to clean copper etc might work

I want to try to clean as much as I can from the cam gears before I try to seperate eveything

Thanks

Dougie

[Dougie SwanParticipant @dougieswan43463]

[lee hawkins 1Participant @leehawkins1]

Hello Dougie

Some people will shout out no no, when I restored old cars years ago, I was able to get hold of neat Hydrochloric acid which I would use to clean heavy rusted back axles, I will admit though back then health and safety was a bit thin, I should imagine the neat stuff will be hard to come by nowadays anyway, But you can use brick acid from builders merchants, they clean bricks down with it, it is Hydrochloric acid mixed, not so strong, just means you leave it longer, it will eat that rust up no problem but it will also carry on eating away at the new metal and can leave it porous, you just got to keep a real good eye on it, soon as you see the rust gone, give it a good wash down with washing up liquid, dry it, and if it is to be left unpainted you will have to give it a coat of light oil

Be very careful take all safety precaution, don't get it on your concrete floor, it will eat a hole in it

Regards

lee

[MM57Participant @mm57]

During my various car restorations I've had a good experience with Bilt Hamber Deox-C

**LINK**

Edited By Martin Millener on 15/12/2013 20:52:17

[DMBParticipant @dmb]

Lee,

What do you mean, "dont get it on concrete floor"? DONT ever use that nasty stuff inside any enclosed space. For sake of your future health, always but always outside in open air – fumes!! I have used it ,outside of course, to get black mill scale off hot rolled steel plate. Works a treat!

Hydrochloric, Sulphuric Acids and the Strong alkali, Caustic Soda. Use them all only outside with eye protection and upwind of the container. Keep container protected from birds and animals. If you have an accidental spill, neutralise with opposites – acid / alkali.

Hope you all take great care for selves and innocent wildlife/pets.

John

[Ady1Participant @ady1]

Malt vinegar dissolves rust, and if you leave it long enough starts to eat the metal as well

Best for dunking, there are various strengths up to 5% and cheap as chips from those big superstore chains

[LambtonParticipant @lambton]

Dougie,

Use electrolysis which is a very safe and effective way of removing rust from iron and steel.
it only uses dilute washing soda (not to be confused with caustic soda) and low voltages from a battery charger.Don't believe theoretical warnings about hydrogen embrittlement as this does not happen with iron castings or steel unless it is of a very high and unusual grade. I have used bulldog clips to clamp the wire to the part being cleaned and after many hours immersed in the electrolysis bath the spring has remained unaffected and still works perfectly.

Do an internet search for electrolysis and you will find dozens of sites manly from the USA. I have used this process extensively and so can assure you that it works very well. Try it !

Don't use hydrochloric or sulphuric acids as they both remove the parent metal as well as the rust and produce a very active surface on the metal which will start to rust immediatelyafter rinsing.

Eric

[Ian S CParticipant @iansc]

If you want to use chemicals, citric acid isthe safe way to go, buy the powder at your local home brew(beer) shop, or super market,
with the electrolitic method, it’s safe for most steels, except the likes of springs, take them out before you start, if they are rusty, replace them. Ian S C

[OuBallieParticipant @ouballie]

Animal feed molasses in a 4:1 mixture, water:molasses respectively, but some have used an 8:1 solution.

Used the former on my spare rusty Austin Seven block, head and other rusty parts, and it removed all the rust and scale.

Keep the solution stirred.

Geoff – Workshop here I come.

[Ian S CParticipant @iansc]

For circulating the fluid, I use an aquarium pump, seems to work well, not needed when using the electrolitic method, there is a natural circulation caused by the electrical current flowing between electrodes. Ian S C

[Dougie SwanParticipant @dougieswan43463]

Thanks for the replies

I am thinking of using the electrolysis method but some of the parts may have bronze bushes fitted

Will this method destroy the bronze?

Dougie

[Ian S CParticipant @iansc]

Dougie, the bronze bushes should be OK. If there is loose rust, knock it off with a chipping hammer, or a wire brush. When it’s finished in the bath, it will require protection as the rust will return as you watch, it’s quicker than paint drying, or grass growing. Ian S C

[Dougie SwanParticipant @dougieswan43463]

Do the parts need to have all traces of oil removed to expose the metal or will it get under the oil and work OK

Dougie

[Ian S CParticipant @iansc]

Remove all the oil you can (you get enough muck in the mix as is), soapy water, or hand wash is good, don't think it has to be complete removal. Ian S C

[nigel jones 5Participant @nigeljones5]

I use electrolysis also

[Dougie SwanParticipant @dougieswan43463]

I have been trying this electrolysis method following some of the advice above

I am using dilute washing soda with a 5 amp battery charger

My results have been less than encouraging

After a 24 hour soak none of the rust deposits have been removed

The liquid is discoloured and bubbles appear on the negative connected workpiece but no rust removal

Does anybody have any suggestions

Dougie

[ronan walshParticipant @ronanwalsh98054]

More amps dougie ? Take it out and give it a rub with a wire brush and start again ?

[I.M. OUTAHEREParticipant @i-m-outahere]

Dougie,

Have a look on youtube and search for mrpete222 or tubalcain as he has uploaded a video of this procedure recently and it may be of interest to you .

Ian.

[Ian S CParticipant @iansc]

You could try a bigger electrode. The one I use is a block of lead, 200 mm x 100 mm x 15 mm. Every now and then I take to it with a chipping hammer, and knock off all the scale build up on the electrode, which reminds me, I better go out and switch it off, because I found a bit of metal that will do the job I'm doing much better, without cleaning up, the bit in the bath will do for another day. Ian S C

[LambtonParticipant @lambton]

Dougie,

I have never had any trouble removing rust from iron castings of mild steel items. A few tips from my experience may help:

• Ensure the sacrificial anode is large enough – within reason the larger the better and if possible made of stainless steel.
• Washing soda need to be at 4 g per litre
• You should aim to be getting at about 2 amps actually flowing through the circuit. Measure this if possible.
• The current can be varied by reducing or increasing the distance between the anode and the work piece as well as by altering the applied voltage.
• As Ian says ensure that all oil, grease etc. is removed from the work piece.

I hope this is of help.

Eric

[Dougie SwanParticipant @dougieswan43463]

Thanks for all of the replys

I swapped my setup into a smaller container and things started to work like I expected it to do

Thanks

Dougie

[Sub MandrelParticipant @submandrel]

Hi Dougie, if the smaller container made a big difference, you may have not made the solution concentrated enough.

Neil

[Ian S CParticipant @iansc]

The main thing that the smaller container would do, is bring the two electrodes closer together, quite interesting to put an ammeter in the circuit, and move the electrode (don't short it, your power supply might not like it), or try lifting the electrode partly out. You will use about the same amount of power regardless of the current, just that as the current is reduced, the time for the job increases, just take your time, the rust took a long time to get there.

Ian S C

[MICHAEL WILLIAMSParticipant @michaelwilliams41215]

A very safe way to do derusting is to use a long immersion in a Gunk tank with frequent agitation and treatment with wire brushes and old paint brushes .

Gunk doesn’t actually dissolve rust but certainly loosens a lot of it up enough to brush off . Gets into tight spaces easily too .

If your engine is a real mess take it to a commercial garage and have it steam cleaned to begin with . They may let you use the Gunk tank as well .

MikeW

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