"Stainless Steel"

[TheyDontWantMusic]

does this look like a stainless steel exhaust to you?

if so, how old do you think it is? how many KM's do you think the car has done with this exhaust?

[vlv8vic]

Dunno mate, doesn't look like the sort of stainless i have in the kitchen.
Is there something called 'mild stainless'?
Popular exhaust shop tried to sell me some extractors they claimed were stainless, when infact they were not stainless steel but some form of part stainless (?)

What's the story behind the pic?

[TheyDontWantMusic]

Dunno mate, doesn't look like the sort of stainless i have in the kitchen.
Is there something called 'mild stainless'?
Popular exhaust shop tried to sell me some extractors they claimed were stainless, when infact they were not stainless steel but some form of part stainless (?)

What's the story behind the pic?

was meant to be a 316 grade stainless exhaust system, custom made (I sourced the mufflers, and resonators)

a lot of the piping is rusting, which was meant to be 316 stainless, while the mufflers are fine, and are apparently 304 stainless.

[VL Berlina 5speed]

looks like untreared 10 year old mild steel exhaust to me

stainless steel exhaust are shine like stainless steel is on straight pieces and on the bends it is covered with a mat grey primer type colour

[TheyDontWantMusic]

anyone work in an exhaust place? or have a stainless exhaust to compare?

[Zuicider]

definatly doesnt look like stainless, why go 316 grade stainless? more exspensive and more salt resistant haha

[Zuicider]

put a magnet on it, the only stainless i know thats magnetic is duplex and that stuff is more exspensive than titanium

[TheyDontWantMusic]

definatly doesnt look like stainless, why go 316 grade stainless? more exspensive and more salt resistant haha

the guy said he only ever used 316 stainless...

stainless steel rulers are pretty rust resistant, and they're very magnetic.

I have a feeling this exhaust will be very magnetic too...

hmm

so, any guesses on the age/km's of the exhaust?

[TheyDontWantMusic]

magnet test:

304 grade stainless mufflers = no stick whatsoever

"316" grade stainless pipe = I struggled to pull the magnet off...

I'm not a happy chappy...

[jatsvl]

NOT stainless, stainless exhaust will shine and as it gets old will have a slight brown stain from extensive heat exposure, not rust staining like the pic.

[nicko]

go and plant that pipe str8 through that shops window mate

[TheyDontWantMusic]

go and plant that pipe str8 through that shops window mate

then I won't have an exhaust

apparently 316 stainless CAN become magnetic if its worked/machined, etc...

however, the mufflers aren't magnetic, and one would assume they recieved just as much machining.

also, my stainless steel manifold isn't magnetic.

of course, 316 is medical grade stainless, resistant to sea water, etc etc, so this should not have rusted at all.

only problem is, I've lost the paperwork

[TheyDontWantMusic]

anyone who cares, this exhaust has been on the car for about a year, during which time, its don't less than 15,000kms.

[lumina01]

gone back and showed the guys that sold it to you, what they say?

[andyman]

its not stainless, that pipe has rust on it, look at the welds etc. it has similar 'browning' to stainless but stainless wont rust.

[FusionX]

but stainless wont rust.

Yes it will.... Add something conductive to it like carbon fibre, throw in some salt water spray and presto, 6 months later the stainless has rusted away. Argh some of the warrenty claims that came back from that discovery (when I used to work in the marine industry).

[TheyDontWantMusic]

gone back and showed the guys that sold it to you, what they say?

I haven't yet, I really should, but I can't find any paperwork :S :P hmm

[TheyDontWantMusic]

sorry the pics are getting bigger

any questions?

[Reaper]

was meant to be a 316 grade stainless exhaust system, custom made (I sourced the mufflers, and resonators)

a lot of the piping is rusting, which was meant to be 316 stainless, while the mufflers are fine, and are apparently 304 stainless.

Stainless steel does corrode with temperature over time. I'd suggest that tube is several years old. I have seen stainless steel which looks more rusted than mild steel. Anybody who says s/s will last forever has their hand on it.

Dunno mate, doesn't look like the sort of stainless i have in the kitchen.
Is there something called 'mild stainless'?
Popular exhaust shop tried to sell me some extractors they claimed were stainless, when infact they were not stainless steel but some form of part stainless (?)

Stainless steel is used to describe a lot of steel alloys with 11.5% chromium or more. There are literally dozens of different grades with the most common being 304(L) and 316(L) etc etc etc......

put a magnet on it, the only stainless i know thats magnetic is duplex and that stuff is more exspensive than titanium

Yeah it is. In it's "natural" un-worked form it isn't but once again, most mechanical processes will cause the s/s to gain some magnetic properties.

From what I can see in the photo above, it could be s/s however it appears the hanger is m/s and may have been welded on with m/s mig wire. Some of the carbon may have bled into the surrounding tube which could cause localized rusting near the weld areas. The best way to tell for sure would be to get a spark test performed by a metallurgist.


Reaper

[TheyDontWantMusic]

i spoke to a guy who had an exhaust done at the same place mine was done, he simply said "thats not stainless" and that his piping hasn't corroded, or rusted at all.

[TheyDontWantMusic]

From what I can see in the photo above, it could be s/s however it appears the hanger is m/s and may have been welded on with m/s mig wire. Some of the carbon may have bled into the surrounding tube which could cause localized rusting near the weld areas. The best way to tell for sure would be to get a spark test performed by a metallurgist.

talking to a guy at work who was a mechanic for quite some time, and also worked with a lot of stainless steel fittings, he said that when welding stainless, to mild steel, you have to use stainless welding wire...

clearly, this wasn't done on my exhaust.

Yes, stainless will become slightly magnetic when worked, however, the piping is just as magnetic as mild steel!!! while the mufflers, and turbo manifold I have are not!

I'd say there's a lot more machining done to the piping on that manifold than to the exhaust piping...

[minux]

Stainless can and does rust over time, can also become magnetic. It does not stay shiny forever. The exhaust i took off the senator was full stainless, looked like ****, certainly was not shiny and had areas of rust.

How about you take it somewhere and have it tested instead of expecting people to know from pictures what metal something is? That way you will truly know if you have been ripped. Will also save you a few sleepless nights on thinking how to get this guy back

[TheyDontWantMusic]

Stainless can and does rust over time, can also become magnetic. It does not stay shiny forever. The exhaust i took off the senator was full stainless, looked like ****, certainly was not shiny and had areas of rust.

but looking at the exhaust, you wouldn't expect the supposid 316 stainless to rust before the 304 stainless mufflers do, unless the piping isn't really 316.

[Wadeo..]

its not stainless mate, just looks like mild steel thats been coated in cold gal or something...

[Reaper]

talking to a guy at work who was a mechanic for quite some time, and also worked with a lot of stainless steel fittings, he said that when welding stainless, to mild steel, you have to use stainless welding wire...

clearly, this wasn't done on my exhaust.

It would appear so. What is beyond me is why people bother with a stainless exhaust to begin with.

Yes, stainless will become slightly magnetic when worked, however, the piping is just as magnetic as mild steel!!! while the mufflers, and turbo manifold I have are not!

That is very difficult to say with any certainty. As per my previous post, get a spark test if you are that worried about it. That will tell you beyond any doubt one way or another. To compare the appearance new fabricated tubes to one that has been on a car for some time is a waste of time.

Reaper