Author Topic: cheap and easy rust removal link  (Read 1579 times)

Online BSA_54A10

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Re: cheap and easy rust removal link
« Reply #15 on: 31.08. 2010 12:19 »
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.
Bike Beesa
Trevor

Offline chaterlea25

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Re: cheap and easy rust removal link
« Reply #16 on: 31.08. 2010 20:20 »
PLEASE DONT BOIL YOUR ALLY HEAD  *eek* *eek* *eek* *eek*

John O R
1961 Super Rocket
1963 RGS (ongoing)

Offline 900triple

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Re: cheap and easy rust removal link
« Reply #17 on: 31.08. 2010 22:49 »
So whats the best way to clean an alloy head then?

Offline bonny

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Re: cheap and easy rust removal link
« Reply #18 on: 31.08. 2010 23:47 »
soda blasting ? or vapour blasting always leaves a nice finish.

Online Brian

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Re: cheap and easy rust removal link
« Reply #19 on: 01.09. 2010 01:44 »
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.