Chrome plating quality

[PT1029]

Over the years I have from time to time seen old bikes with newer parts on, usually the newer chrome has rusted far more than the original.
My none scientific conclusion confirmed today walking by the river when I saw an old bike that had been hauled out of the river:

Hard to see in the photo, but in the flesh you can easily see the Bayliss Wiley letters on the barrel!

[rogerzilla]

Received wisdom is that older chroming processes used nastier chemicals which aren't allowed now. Same goes for old Sturmey-Archer hubs, where the internals are a lovely gold/titanium colour rather than the usual black - apparently a form of hardening that is no longer used.

[PT1029]

Yes, I think you are right!
Applies else where. I went to buy some high tensile steel bolts, asked why they were not black (as I remember from years ago), and was told due to new environmental constraints, a different plating colour.
Ditto weldite rear axles. I order the cr-mo ones for use at work, they changed from a goldish colour to silver (I thought they had sent to wrong ones, as the basic ones used to be silver). I was told no longer gold as they could not use the heavy metals which resulted in the gold colour.
I have yet to try impressing customers by telling them that their new axle is lighter as it no longer contains heavy metal!

[slowster]

In his book Touring Bikes Tony Oliver wrote

Modern chroming techniques...do not include the copper and nickel layers found on older frames. Copper forms a non-porous barrier stopping moisture reaching the steel whereas chrome, being porous, allows the steel/water reaction to occur - rusting.

I wonder what the standard is for chromed parts in the marine industry. People who buy multi-million pound yachts would not tolerate the sort of rapid rusting to deck fittings etc. that might otherwise be expected with modern poor standards of chroming and daily exposure to salt water etc. (unless maybe polished marine grade A4 stainless steel is used instead of chrome).

[Jdsk]

Yes, there's enormous use of stainless steels on boats.

And because of that chandlers are a useful source of lots of bits.

Jonathan

[rogerzilla]

In his book Touring Bikes Tony Oliver wrote

Modern chroming techniques...do not include the copper and nickel layers found on older frames. Copper forms a non-porous barrier stopping moisture reaching the steel whereas chrome, being porous, allows the steel/water reaction to occur - rusting.

I wonder what the standard is for chromed parts in the marine industry. People who buy multi-million pound yachts would not tolerate the sort of rapid rusting to deck fittings etc. that might otherwise be expected with modern poor standards of chroming and daily exposure to salt water etc. (unless maybe polished marine grade A4 stainless steel is used instead of chrome).

A lot of the Oliver book is urban legend, although I'm sure he built very nice frames. A quick Google of UK chrome platers shows they still use the copper and nickel undercoats. There is a BS covering the process anyway.

http://derbyplating.co.uk/the-process/

[col64]

derby chrome is prob the best in uk

[slowster]

In his book Touring Bikes Tony Oliver wrote

Modern chroming techniques...do not include the copper and nickel layers found on older frames. Copper forms a non-porous barrier stopping moisture reaching the steel whereas chrome, being porous, allows the steel/water reaction to occur - rusting.

I wonder what the standard is for chromed parts in the marine industry. People who buy multi-million pound yachts would not tolerate the sort of rapid rusting to deck fittings etc. that might otherwise be expected with modern poor standards of chroming and daily exposure to salt water etc. (unless maybe polished marine grade A4 stainless steel is used instead of chrome).

A lot of the Oliver book is urban legend, although I'm sure he built very nice frames. A quick Google of UK chrome platers shows they still use the copper and nickel undercoats. There is a BS covering the process anyway.

http://derbyplating.co.uk/the-process/

Tony Oliver stated that he had a few of his early frames chrome plated, but then refused to offer it as an option to customers, and the implication is that either the quality of the chroming (including the layers underneath) was poor and/or he became too concerned about the unsuitability of thin wall tubing for chroming.

When he started building frames there were probably many more chrome platers in the UK than even 20 years ago, but I suspect the quality of the work was variable even for plating supposedly done to the relevant standards. I suspect that this is one of those things where you get what you pay for, and if someone absolutely wants chrome plating, then they need to be prepared to pay what I imagine is the very high price charged by the likes of Derby Plating for top quality work.

[rogerzilla]

He talks about hydrogen embrittlement from the process, which is probably right. I don't think chrome is very good for the underlying metal, although it is certainly nice to have on a chainstay.