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intensem1
12-12-2005, 05:51 PM
I have spoken to all local and a few interstate wheel refurbishing companies.

They all say the same thing that if you chrome the bbs bolts it softens them.

Has anyone had any experience with this, it seems alot of guys on VW vortex chrome them with no problem.
syncro
12-12-2005, 06:24 PM
I am not a metalurgist, but I have never heard of this??????
imported_brackie
12-01-2006, 08:05 PM
I am not a metallurgist, but I have never heard of this??????
Nor me. I assume the chroming is done by electrolysis. Shouldn't soften the metal. If heat has to be applied to do it, this could anneal it.
alex g
13-01-2006, 05:10 PM
i have factory chrome bbs rs bolts,but that sounds like a crok, i am waiting on a gold set so i may have a complete 120 for sale
aprr32
13-01-2006, 06:44 PM
Its called hydrogen embrittlement and it can lead to a structural failure within the grain of the metal.
roccodingo
13-01-2006, 11:31 PM
Its called hydrogen embrittlement and it can lead to a structural failure within the grain of the metal.

Yeah, this is correct, Hydrogen embrittlement is a by product from the electrolytic process used in chroming ( also happens with welding !!)

In the plating shop, what is required after the chrome has been applied, is for the part to be " de embrittled" by placing in an oven for a specified period of time commensurate with the cross sectional area of the part and allowed to heat soak. You need to do this no longer than 1 1/2 Hrs after removal from the chroming tank..

From memory the temp for 4140 is 150 Deg C, but if you ring any metallurgical business, they should set you straight, If the plating shop is any good THEY will know this, happens with all types of plating, Zinc, Gold , Silver etc..

Also the chances of hydrogen embrittlement increase with the higher strength and / or heat treatment of the steel components.

HTH..
alex g
14-01-2006, 07:28 AM
learn something evryday, makes scence when you think of it
syncro
14-01-2006, 07:42 AM
I'll have to keep that one in the memory so I can amaze my friends with my knowledge! (Just got to work it into the conversation though...) :roll:
mrgolf
18-01-2006, 09:11 PM
I reckon they would look a bit odd chromed, anyway. I took my bolts off, and I am in the process of cleaning them. Hit them with a wire wheel, and they come up beautiful. Too bling and they will take away from the polished lip. If you want extra bling, go with gold or black or something...