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Chrome plating aluminium please help update

February 3, 2009

Hello,

I'm motorcycle builder from Poland, here in PL is very difficult get some help about galvanization, so I ask specialists like You. People in PL are saying that chrome plating aluminium is nearly impossible and I'm crazy...

I would ask about chrome plating aluminium, I researched Your information and want to try.
Due here in Poland we have problems with it (only 3 companies do that - very expensive),
I have in my city friend in company that makes chrome plating steel only I would try this way with him:

At home I would do with rinse at every point:
1. cleaned in a non caustic cleaner (what formula can I use) - I can clean with
clean benzine and lime- is this enough?
2. one minute in 10-25% sulfuric acid
3. Zincate 60 sec with:
caustic soda ⇦liquid caustic soda in bulk on Amazon [affil link] .............525g
Zinc oxide...............100g
ferric chloride ⇦this on eBay or Amazon [affil links] crystals.1g
Rochelle salt (potassium sodium tartrate) ⇦this on eBay or Amazon [affil links] .........10g
4. dezincate it - now is the question what can I use - it's difficult to buy nitrous acid
can I use 37% sulfuric acid then? How long if so.
5. Again zincate for 15 sec

and now I would take this part and drive 10 miles to company which will do
electro cleaning, electroplating nickel, electroplating chrome.

What result will I get with? can this element be on the way for some time? Maybe I should take this part dipped in the water on the trip to company?

Now what I tried is making zincate bath with above parts, I placed there piece of aluminium for 60 sec, I took it off ant it was with lot of gray/black coat ant this coat could not get off in the water since I helped it with hands. Is this coat normal? after I removed this fat coat, aluminium seems to look like with zinc.

Please help,

greetings

Pawel Wiecek
Building custom motorcycles - Opole, Poland

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February 15, 2009

hi Pawel

I cannot help you with the make up of the solutions but chrome plating on aluminium is quite simple to do if you have the correct solutions .


as long as the parts are correctly cleaned , and etched , double zincated , (yes , the aluminium will go dark grey after zincate )
pyro copper plated , then nickel and finally chrome plated.

as your taking the parts to a professional plating company I won't need to go into detail with the cleaning processes as they will already know how to do it .

hope this helped

Jay Smith
- Essex, UK