Chroming Exhausts

Simple question. The down pipes are stainless are they not? They are in need of cleaning up, so can the stainless be chromed successfully? They have discoloured plus have some moderate rusting/pitting.

There is a place very near me who do this but can stainless be chromed and would it prevent them from discolouring in the future?

 

The down pipes on Tridents etc are black chrome on s/s.
I guess that 3cyl Thunderbirds are normal chrome on s/s, but don't take that as 'gospel'.
Chromed down pipes have blued since before Noah was a lad, except for those that Honda (and perhaps others) double skinned.
Some chrome plating companies apparently don't like chroming used exhausts in case the carbon inside the pipes contaminates their chrome solution.
As an alternative suggestion (and I don't know if it is possible, though I would have thought it would be), could the pipes be given an industrial strength polishing to get the finish you want? And would it be a better/cheaper (I am a Yorkshireman after all!!) solution to your problem?
There ... that's another can of worms opened!

 

I'd echo what Steve said about chroming companies not wanting to handle used exhausts as they will contaminate thier chroming solution - picked this up from another forum when I was looking into it.

 

The place I referred to do exhausts, they did my RD's about 5 years ago. Top notch job they did, NOT cheap though and takes a couple of months.

No blueing too! They look as good as new.

I'll take a look at that you tube video but I feel they need industrial cleaning.

 

Just a suggestion for you Tone, but have you thought of using a buffing/polishing wheel to clean up the downpipes? I did this once on a set of Bandit downpipes that looked REALLY cruddy, but after course/medium/fine polishing they looked like brand new chrome pipes.

A kit something like this would do it:

http://www.ebay.co.uk/sch/Power-Tools/61573/i.html?_nkw=bench+buffing+wheel&_frs=1

 

Worth a punt I think. I guess you use it with some polish/cleaning solution. I usually use Mer polish and sometimes Autosol. I know Autosol is pretty abrasive but maybe what's needed?

 

Just polished to death my headers on my trx850 and they went straw coloured on the first instance!!

 

Once stainless steel is heat affected, either straw coloured or blue there's not much you can do.
The heat can and sometimes does deplete the chrome content of the stainless as time and heating progress. By polishing even with the most gentle polish you are effectively removing some of the parent material and so in the case of stainless, some of the chrome. Even Grade 1 diamond polishing paste does this to a very much lesser degree. Just like using different grades of emery cloth to remove marks from plain metal, (the higher number, the finer the emery grit), polish does much the same thing.
To answer your question, chrome plating will restore the finish quality but will need to be repeated at some future date unless you are prepared to pay for multiple coating of hard chrome and even then it will not last forever as polishing, scratching from road grit and dust etc, atmospheric exposure, damp, etc, etc will affect the finish.

To finish Material Science 101. Stainless steel is affected by chloride corrosion caused by atmospheric sodium chloride, (salt). It's in our atmosphere because we live in a maritime temperate zone and so the atmosphere is damp and we are surrounded by the sea.

 

By co-incidence I took the Bonnie to the Beds VMC meet in Shefford last night and spoke to a couple of chaps there who obviously know their onions and they pretty much backed up all the advice given above re, re-chroming.

Thanks all for your input guys.

 

I seem to remember seeing something on Del Boy's Garage about polishing stainless with Coke and kitchen foil. Might be worth a squint?

 

Huh! One just cannot get good worms these days!

 

Nearly correct Al, Stainless was an old kitchen green pad to remove the bad bits and then solvol chrome was the kitchen foil and solvol if i remember correctly