Soft cleaning of corroded ally?

[T i m]

Hi All,

I'm tidying up an old Honda CB 'Two Fifty' and whist at the Kit Car show today i nearly bought some cleaning fluid for such things that apparently was mostly phosphoric acid (if I remember correctly)? It's mainly for around the cylinder barrel fins, the outer casings / rocker cover were lacquered (much is now missing) but I can take them off and clean them up on the bench ok.

This chemical solution seemed quite expensive so I didn't bother and guessed there may be some other 'fluid' out there that may well be designed for a different role that could work equally well but without the cost?

Ideally it might also be a bit more gentle .. less likely to damage paintwork etc (I'd rather it took longer or a few applications than did damage elsewhere) and available cheaply and easily?

Like using cola to remove oil from yer concrete drive sorta thing?

All the best ..

T i m

[T i m]

Ok will do, cheers Geoff ;-)

All the best ..

T i m

[geoff]

In message , T i m writes

[e-mail]

One of my suppliers does just such a thing, their phone number is at work

[Dave Baker]

Sodium hydroxide dissolves aluminium oxide, as well as the aluminium itself. It's found in drain cleaner and oven cleaners although you should be able to buy it readily from a chemical supplier. However the best way to clean corroded aluminium is vapour blasting, which is glass beads in a water jet, or blasting with other soft abrasives such as walnut shell. Most acids and other strong chemicals will leave the surface grey and then you also have to clean that off which defeats the purpose.

For areas you can reach easily a small rotary wire brush in a drill followed by Scotchbrite is good.

Finally the scrap yard and engine reconditioners trick is sod the cleaning and spray it with aluminium wheel silver paint which covers a multitude of sins.

[Mungo "Two Sheds" Toadfoot]

Get the cheapest cola you can find - it has phosphoric acid in it.

Si

[T i m]

Ok, so as I don't know if I have a local chemical supplier the other stuff should be found in any supermarket / hardware store / shed.

I've heard that process mentioned (Vapour blasting) but didn't know what it was (so thanks).

Well, grey is better than fluffy white Dave ;-)

Ah, well this is in-between yer typical air-cooled motorcycle cylinder and head fins so not much room.

Nice. Don't get me wrong, I'm happy to brighten up such things with an acid-etch primer followed by a squirt of 'Five wheel Silver' or similar but I'd prefer cooling / hot parts running naked as such. ;-)

All the best ..

T i m

[geoff]

BTW, if you didn't know, I also have a shot blast cabinet

[geoff]

Just remembered - I have 5 litres of phosphoric acid somewhere out the back

It's the real thing ... as they say

[T i m]

What, pure Cola Geoff! ;-)

All the best ..

T i m

[geoff]

Why not come over for a tasting ?

[T i m]

Was it Peter Kay .. his Mum used to buy Rola Cola because she could get 8l for 40p!

cola thing was what I was looking for first, just to see how much difference it could make whilst carrying little risk (to me or machine).

Stage 2 might be something 'harsher' but I'll probably only do that if:

Something more 'domestic' doesn't work (or work well enough)..

The bike runs well enough to make it worthwhile.

Someone offers me the right stuff at the right price ;-)

All the best ..

T i m

[T i m]

Hmm, cola AND a shot blasting cabinet .. it would be rude not to eh! ;-)

All the best ..

T i m

[geoff]

In message , T i m writes

How many litres do you think you could make from this ?

[T i m]

stuff on ally?

All the best ..

T i m

[geoff]

It's phosphoric acid - enough pokey cola to last you a life time

Adopts welsh dirty sanchez accent

"there's only one way to find out"

You could always phone Kamco up, they are only just down the road in Park Street, and are reasonably helpful

[The Medway Handyman]

Alluminium brighteners are either phosphoric acid or hydroflouric acid. The former is fairly benign, the latter is very nasty stuff indeed, but works better AFAIK.

[geoff]

In message , The Medway Handyman writes

They both dissolve your bones, although , where I wouldn't be too concerned dipping my fingers into phosphoric acid, I'd rather not be in the same room as hydrofluoric

[Pete C]

For a general cleaner for aluminium try a dishwasher tablet dissolved in water.

Don't scrub it on highly polished surfaces (there may be impurities in it ) also keep it off paintwork as much as possible (it's a bit caustic).

It should have silicates in which prevent corrosion by the other ingredients.

cheers, Pete.

[dennis]

Don't get it on the skin, it says that it is corrosive for a reason.

[T i m]

Ah, ok, what sorta volume of water would you suggest then please Pete (/ tablet)?

Understood. Luckily the tank and plastics on this bike come off with just 3 screws so can be got right out of the way.

Ok.

All the best ..

T i m

p.s. In case you didn't see my thanks to those who offered help re my recent washing machine project, 'thanks' very much for the heads up on sealsdirect Pete. ;-)