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Dechroming exhaust pipes for painting

I was hoping you could enlighten me on dechroming, as I have a couple parts I would like to dechrome. I am wanting to strip the chrome off of a couple exhaust pipes on my Honda Shadow, and than end up painting them black. Is my only choice using hydrochloric acid to strip the chrome, do I need to remove the nickel as well after. Or is it possible just to lightly sandblast the chrome and paint over.

Jerry Petkau
hobbyist - Swift Current, Saskatchewan, Canada
2004

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I recently attended a powder coating workshop where several powder coaters claimed that they could successfully powder coat after a light sandblast. The same may be applicable to wet paint. But if it was me, I'd probably strip the chrome first and then try the light sandblast. Obviously, the high temperature of exhaust systems accentuates any weakness in the plan.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2004

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I am also a Shadow owner with the same goal of painting my exhaust pipes black. I have never stripped chrome before so could you give me some more details to this method.

Thanks,

Dennis Alfonso
- Bayonne, New Jersey, USA
2005

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Hi, Dennis. The general issue is that chrome doesn't "wet" and is exceptionally difficult to get paint to adhere to. The chrome can be very quickly, but not necessarily safely, stripped with muriatic acid ⇦ this on eBay or Amazon [affil links] if you know what you are doing and are wearing proper protective equipment.

But decorative chrome plating is actually nickel plating followed by chrome, so you are still left with nickel. Nickel requires different chemistry to strip. And nickel is a passive metal that is itself difficult to paint.

So, short of also stripping the nickel (which would require sending it to a plating shop), the plan that is being discussed here is stripping the chrome then sandblasting the nickel for some tooth and some fresh surface. Considering that this is very high temperature exhaust piping, though, I have some doubt about it being a hundred percent satisfactory.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

Any luck with the Honda Shadow exhaust pipes? Was de-chroming required?

Jeff Viney
ATV repair - Primrose, Wisconsin, USA
June 30, 2008