Cleaning tarnished stainless exhausts

[MartDude]

I've got the exhaust off at the moment,as part of a general fettle, and thought I'd take the opportunity to clean them thoroughly. A friend on here recommended Optiglanz

http://www.hein-gericke.co.uk/techni...er-250-ml.html.

However, I've read that this sort of cleaning product, although effective initially, can cause the stainless steel to discolour more rapidly in the future; e.g. this comment from a BMW forum :

"Works great the first time and makes polishing really easy.
BUT it brings all of the chromium in stainless to the surface and your pipes will discolour even quicker afterwards."

Anyone here got any experience of this stuff, or similar products? Any suggestions for alternative products/methods?

[mangocrazy]

I'm always a bit suspicious of 'miracle' cleaners, but don't have any proof or experience of Optiglanz. I know that the type of stainless used on 'Priller downpipes is pretty ropey, with a high steel content and low chromium content, so there may well be something in what the BMW forumer says.

I'm planning on taking a different tack in the near future and getting my downpipes electroless nickel plated. This is a treatment that has very high corrosion resistance and is used to treat stainless steel when used in harsh or marine environments. Sounds bang on to me. I'm intending to get a large amount of bits gathered up and take them all to be done at the same time, hopefully avoiding minimum weight/quantity charges.

[MartDude]

I'm planning on taking a different tack in the near future and getting my downpipes electroless nickel plated. This is a treatment that has very high corrosion resistance and is used to treat stainless steel when used in harsh or marine environments. Sounds bang on to me. I'm intending to get a large amount of bits gathered up and take them all to be done at the same time, hopefully avoiding minimum weight/quantity charges.

Hmm, that's a good idea - a friend owns a plating & anodising company - hadn't thought of that.

As a side issue, this friend is experimenting with nickel-plating plastics; we've had a few pub conversations about doing the Fut - might come out a bit like this

[D-Rider]

However, I've read that this sort of cleaning product, although effective initially, can cause the stainless steel to discolour more rapidly in the future; e.g. this comment from a BMW forum :

"Works great the first time and makes polishing really easy.
BUT it brings all of the chromium in stainless to the surface and your pipes will discolour even quicker afterwards."

I'm no chemist .... but how ....

[Samray]

I'm no chemist .... but how ....

It's a kind of Chrysopoeia.
Involves the use of a philosophers stone.

[blinkey501]

I bought my motads of the falcohilist and though they was in good condition i took them to a friends fabrication shop and polished them on a buffing wheel and they came up superb...
http://www.ebay.co.uk/itm/6pc-POLISHING ... 3f13cd8c56

His was a pedestal mounted one like a bench grinder, a lot of pressure will be required for best results... Hope this helps

[D-Rider]

My technique on Falco exhausts is an opening attack with optiglanz. Assuming my hands survive (because I can never be arsed to put on protective gloves), I then follow that up with an assault with Autosol and wire-wool.
The battle is completed with a gentle buffing.

[MartDude]

My fabricator friend who's helping me with re-furbing the exhaust (replacing corroded spring tabs, link pipe) advises buffing. As he's got all the kit for this, I'll perhaps give that a go first. However, I did come across this (from one of the links below : "Mechanically cleaned parts are not quite as corrosion resistant as acid pickled material because mechanical cleaning leaves some scale residues and often some residue from cleaning. It can be used as a preparatory step before acid pickling." Need to think a bit more.

In the meantime, I've been having a bit of a trawl for SS cleaning info. Here are what I consider to be the most informative results (but I did learn a lot about cleaning SS kitchen equipment, in passing)

http://chemistry.about.com/gi/o.htm?zi= ... sdata.html

http://hghouston.com/resources/material ... teels.aspx

http://www.azom.com/article.aspx?ArticleID=1142

And here's one on Optiglanz itself; included for the comedy value of Google Translate

http://translate.google.co.uk/translate ... md%3Dimvns

One tip I picked up from the trawl - don't use wire wool.

[MartDude]

However, I've read that this sort of cleaning product, although effective initially, can cause the stainless steel to discolour more rapidly in the future; e.g. this comment from a BMW forum :

"Works great the first time and makes polishing really easy.
BUT it brings all of the chromium in stainless to the surface and your pipes will discolour even quicker afterwards."

I'm no chemist .... but how ....

Here's the full quote :

"I have a big pot of a similar substance
It's called pickling paste, which is used to remove the weld disscoloration after weding.
Works great the first time and makes polishing really easy.
BUT it brings all of the chromium in stainless to the surface and your pipes will discolour even quicker afterwards.
Quick fix of you are going to sell the bike.
You cant beat elbow grease and solvol.
Been there and done it looking for the panasear of easy polishing."

I read a few similar comments on other forums, though they didn't mention the chromium 'migration' point. I wonder if he was referring to the removal & restoration of the chromium oxide layer?

[mangocrazy]

Whatever you do, I'd steer clear of wire wool, unless it's stainless wire wool. The best bet is Scotchbrite (or an equivalent), which is available in 3 grades that I'm aware of. With ordinary wire wool, all you are doing is to leave minute fragments of mild steel embedded in the stainless, which will rust at first contact with water and leach all over your handiwork.

[BikerGran]

Scotchbrite and washing up liquid is fantastic on alloy - but you need to clean off the washing up liquid with something like meths afterwards.

Don't have anything stainless on my trike so I wouldn't know about that!

[mangocrazy]

Scotchbrite and washing up liquid is fantastic on alloy - but you need to clean off the washing up liquid with something like meths afterwards.

Don't have anything stainless on my trike so I wouldn't know about that!

Works very well on Stainless, as well. The trouble is that the grade of stainless used on 'Priller exhausts is very poor - loads of impurities. So no matter how good a finish you get, it doesn't last long.

[BikerGran]

The obvious answer is aftermarket exhausts!

[fatboy]

First I must say I have not looked at the links re cleaning/polishing and Im NOT a metalurgist but have an elementary understanding of chemistry/physics. an NVQ in welding and a bit of experience making S/Steel water cooled Chinese Wok Burner cookers
There is no way a chemical cleaner can alter the overall crystaline stucture of a hard alloy such as S/S, the only thing that could do this is extreme temp such as welding (chromium migration a myth)
As S/S is an alloy its quality is only as high as its composite specification, abrasive and chemical cleaners can leave the surface of lower grade material open to oxidisation
We used to use different grades of ScotchBrite to polish out S/S welds but found almost all types of solvent cleaners would leave a tarnish on even the high grade stainless needed for a 15 burner cooker

[MartDude]

The obvious answer is aftermarket exhausts!

That's what I've got