Refinishing stainless steel (fabspeed) mufflers
03-17-2016, 12:05 PM
#1
Instructor
Thread Starter
Refinishing stainless steel (fabspeed) mufflers
First off, thank you rennlist members and fabspeed for putting together a group buy on the x-pipe / cats!
I had the rsr mufflers (robin sun modified) on my car. Loved the sound, but was concerned about the increased noise by adding the x-pipe. I was told that the fabspeed maxflows / x-pipe would be similar to the rsr mufflers / stock cats.
I found a set of used fabspeed mufflers that were crusty and rusty. Being stainless steel, I thought I would give it a whirl and try to clean them up.
BEFORE:
After some interweb searching, I was armed with:
P21s Metal polishing soap
Scotchbrite pot scrubbers
000 steel wool (really should have used 0000 as it would not scratch as much.)
1500 grit wet sand paper
Drill with scotchbrite pad on backer.
(5) spare evenings.
I got most of the surface rust off. Some pitting and spotting on the pipes proved very difficult to get out. I used too abrasive (or too much force) with the steel wool. Lots of tiny swirl mark scratches.
AFTER P21S CLEANING:
My angle grinder (and bench grinder) had too high of an rpm. I was stuck with a cordless drill and polishing wheel.
AFTER QUICK POLISH:
I had the rsr mufflers (robin sun modified) on my car. Loved the sound, but was concerned about the increased noise by adding the x-pipe. I was told that the fabspeed maxflows / x-pipe would be similar to the rsr mufflers / stock cats.
I found a set of used fabspeed mufflers that were crusty and rusty. Being stainless steel, I thought I would give it a whirl and try to clean them up.
BEFORE:
After some interweb searching, I was armed with:
P21s Metal polishing soap
Scotchbrite pot scrubbers
000 steel wool (really should have used 0000 as it would not scratch as much.)
1500 grit wet sand paper
Drill with scotchbrite pad on backer.
(5) spare evenings.
I got most of the surface rust off. Some pitting and spotting on the pipes proved very difficult to get out. I used too abrasive (or too much force) with the steel wool. Lots of tiny swirl mark scratches.
AFTER P21S CLEANING:
My angle grinder (and bench grinder) had too high of an rpm. I was stuck with a cordless drill and polishing wheel.
AFTER QUICK POLISH:
Last edited by jason89i; 03-17-2016 at 01:04 PM.
03-17-2016, 12:09 PM
#2
Instructor
Thread Starter
It has been rewarding, but I NEVER want to do this again. I just couldn't bring myself to bolt these (or the other mufflers) to such a nice xpipe.
What should I be using to polish / protect the stainless steel exhaust?
I heard a silicone based polish is the best protector.
I would like to polish everything to remove the surface impurities (iron) and keep the stainless steel from rusting again.
I just tried Blue Magic. It was readily available at the parts store.
Any recommendations?
QUICK POLISH OF X-PIPE
What should I be using to polish / protect the stainless steel exhaust?
I heard a silicone based polish is the best protector.
I would like to polish everything to remove the surface impurities (iron) and keep the stainless steel from rusting again.
I just tried Blue Magic. It was readily available at the parts store.
Any recommendations?
QUICK POLISH OF X-PIPE
Last edited by jason89i; 03-17-2016 at 12:31 PM.
03-17-2016, 01:54 PM
#5
Was the steel wool that you used stainless or carbon steel? If mild steel, you may see corrosion appear very quickly.
For best results pickle/passivated post cleaning.
Looks good.
For best results pickle/passivated post cleaning.
Looks good.
03-17-2016, 04:00 PM
#7
Instructor
Thread Starter
Trending Topics
03-17-2016, 04:13 PM
#8
Might want to try Google searching your area for "stainless passivation".
Most metal coating shops; chrome, anodize, zinc plate, phosphate; use passivation for cleaning prior to coating.
Passivation removes the surface contamination created when stainless steel is machined and fabricated. These contaminants can result in premature corrosion, ultimately damaging the component. In addition to surface cleaning, passivation forms a thin, transparent oxide coating that fights selective oxidation.
HTH
Most metal coating shops; chrome, anodize, zinc plate, phosphate; use passivation for cleaning prior to coating.
Passivation removes the surface contamination created when stainless steel is machined and fabricated. These contaminants can result in premature corrosion, ultimately damaging the component. In addition to surface cleaning, passivation forms a thin, transparent oxide coating that fights selective oxidation.
HTH
03-17-2016, 06:03 PM
#9
To add to the accurate post above...
Passivation is essentially a method of removing 'free iron' and contaminants from the surface of stainless steel. Often used in architectural applications eg hand rails etc.
Ever seen spots of brown on a stainless hand rail? If so, it was most likely not passivated. Even metal dust from the shop environment settling on the stainless will cause this once exposed to moisture. Also, contact with tools and steel benches as mentioned above.
The reason that I bring up the steel wool is that (in a previous engineering role) I recall a customer cleaning graffiti off of a nice stainless sign that we manufactured. Few days later the path of the steel wool was a nice shade of brown.
There are some citric acid products that are available that can be neutralized and disposed of easier than the nitric acid products (but is still hazardous). The nice thing about the citric products is that it is very hard to 'etch' the surface by over exposure. I've left parts in a bucket overnight (in citric).
http://www.citrisurf.com/products.htm
Pickling (paste) is essentially a stronger application of acids (nitric and hydrofluoric acid). This can be used to remove weld discoloration (blue, gold) on stainless but will effectively remove the free iron. This stuff is usually available at welding shops but is hazardous and can easily etch the surface.
...I tend to over think things. Your exhaust looks great!
Passivation is essentially a method of removing 'free iron' and contaminants from the surface of stainless steel. Often used in architectural applications eg hand rails etc.
Ever seen spots of brown on a stainless hand rail? If so, it was most likely not passivated. Even metal dust from the shop environment settling on the stainless will cause this once exposed to moisture. Also, contact with tools and steel benches as mentioned above.
The reason that I bring up the steel wool is that (in a previous engineering role) I recall a customer cleaning graffiti off of a nice stainless sign that we manufactured. Few days later the path of the steel wool was a nice shade of brown.
There are some citric acid products that are available that can be neutralized and disposed of easier than the nitric acid products (but is still hazardous). The nice thing about the citric products is that it is very hard to 'etch' the surface by over exposure. I've left parts in a bucket overnight (in citric).
http://www.citrisurf.com/products.htm
Pickling (paste) is essentially a stronger application of acids (nitric and hydrofluoric acid). This can be used to remove weld discoloration (blue, gold) on stainless but will effectively remove the free iron. This stuff is usually available at welding shops but is hazardous and can easily etch the surface.
...I tend to over think things. Your exhaust looks great!
