cheap and easy rust removal link

[bonny]

i didn't know good old vinegar could do a turn for rusty classic bits !   

http://www.cookhaus.co.uk/vinegar/index.htm

[brackenfel]

Hi Bonny,
Wow, just vinegar   Makes me think twice about putting it on my fish 'n chips now though....

Thanks for posting that, I'll go to Adsa in the week...
Adrian

[orabanda]

Another good one is Coca Cola; just pour some on steel and watch it clean up!

[muskrat]

Good stuff. Changing my eating and drinking habits. Now wot to mix the rum with?
Cheers

[BSA_54A10]

All metal oxides are alkaline.
Alkalines react with acids
Vinegar is an acid ( acetic to be precise )
Coke a cola is acid ( phosphoric )
Rust converters / removers are acid ( phosphoric , nitric, hydrochloric in varying ratios )
The trick is to find one that leaves the surface in a condition that is useful.
Molassis is an excellent rust remover that leaves the steel with a porous complex phosphate coating that takes oil really well so is really useful for tools but dose not take paint very well.

[bonny]

i'm going to buy a couple of small bottles and see for myself how well this works .

[900triple]

I've got some alloy in a malt vinegar bath just now. A monobloc body, an oil tank filler cap.

Any likely hood of damage overnight? Chemistry wasn't my strong point at school!

[MG]

The (original) Monoblocs and the filler caps are made from a zinc alloy, and I wouldn't put that into acetic acid (vinegar).
In the best case they will turn dark-grey or even black overnight, in the worst case they will slowly disintegrate.

The bore for the carb slide is a functional surface and I wouldn't risk getting this damaged, roughened, etc., so better take the parts out (and rinse them with water!)

[900triple]

Out!

This forum is great...is there anything it doesnt know?

What about an old alloy cylinder head (T110) which has a layer of oxide protecting it?

Or am i best just sticking to iron and steel?

Cheers

[900triple]

I've taken the monobloc body out (2 hours?), which was very grubby and gave it a going over with a toothbrush followed by a hose down and then a rub with a clean cloth...

Result is a new looking carb body!

Alloy bits didnt appear to be at all affected Is that because the acid can't permeate the oxide?

[bonny]

here is a link to another forum i hang about on , its all about general metal bashing , and some of the members are into bikes too , this is a link to where i found the vinegar trick, http://www.mig-welding.co.uk/forum/index.php ,and this gent graffian is interesting too
http://www.mig-welding.co.uk/forum/showthread.php?t=15914&highlight=vapour+blasting

anyone else here a member on there ?

[mike667]

i've had lots of experience with removing rust from tanks  -  the coke/vinegar and even molasses (yes!) all work OK for light to mild rust -  but none of these are great if there is  considerable  rust.
the two best i've found are phosphoric acid, which works really nice and isn't really corrosive (or smelly) or muric acid ( AKA diluted hydrochloric acid). The muric acid works well too and is quick and easily available - i like to buy "the works" toilet cleaner which is available at most hardware stores (or any department store) and its main ingredient is hydrochloric acid - add to the tank and swish a few times for about an hr and rinse well followed by a WD40 fogging (or marvel mystery oil swishing) to prevent flash rusting. I then typically add a cap or two of castor 2-stroke oil in the gas to prevent rust from forming again (no the bikes exhaust doesn't smell like castor - bummer i know). Donre the muric acid treatment to probably half a dozen tanks, always with good results - just don;t get it on the paint!!!

m  

the works toilet cleaner is also great for removing rust stains from driveway /concrete, probably clear up acne well to

[Brian]

Just one more little thing, after you have cleaned the rust out by whatever method you choose and have thoroughly washed it out with water put a couple of cups full of metholated spirits in and swish it round and tip it out, then sit he tank in the sun and let it dry.

Metho absorbs the water so there is no moisture left lurking in hard to get at places. There is a fancy name for it, I think its hydroscopic or something like that but simply means it will absorb water.

If you are really keen you can tip the metho back into a glass, add a teaspoon full of salvital and enjoy a glass of poor mans champagne 

[muskrat]

I use both the molasses and metho that way it's like rum to drink !!!
If you suspect water in your fuel, a cap of metho will help it burn.
For bad rust I use POR15.
Cheers

[mike667]

Just one more little thing, after you have cleaned the rust out by whatever method you choose and have thoroughly washed it out with water put a couple of cups full of metholated spirits in and swish it round and tip it out, then sit he tank in the sun and let it dry.

Metho absorbs the water so there is no moisture left lurking in hard to get at places. There is a fancy name for it, I think its hydroscopic or something like that but simply means it will absorb water.

If you are really keen you can tip the metho back into a glass, add a teaspoon full of salvital and enjoy a glass of poor mans champagne 

acetone also does this....

[BSA_54A10]

Zinc castings get a really tight oxide coating due to the chemistry of the alloy.
They will be slow to start reacting to acids, particularly reducing acids, but when they do they will dissappear before your eyes in a matter of seconds.
The best thing that I have found for zinc parts is a good boil in dishwasher detergent.
They will get a light coating of hydroxide ( because the detergent is alkaline) which is medium grey and will rub off with a tooth brush dipped in warm water.
To get a brighter than new finish , follow the boil with a soda blast.

The light metals are all highly soluable in oxadizing solutions which in laymans terms are most acids and all alkalis so you have to be careful with aluminium and zinc based parts.
Iron OTOH is almost insoluable in strong alkalis so the best way to clean up your barrels or head is to boil them in caustic soda which will also degrease them as well and if left in long enough strip off the paint.

[chaterlea25]

PLEASE DONT BOIL YOUR ALLY HEAD 

John O R

[900triple]

So whats the best way to clean an alloy head then?

[bonny]

soda blasting ? or vapour blasting always leaves a nice finish.

[Brian]

A friend has just had two alloy heads soda blasted and I was very impressed with the finish. A nice clean dull sheen finish, I would certainly recommend it.

I haveny had any experience with it but there is also aqua blasting which I believe is also very good.