I've seen some post about guys removing all paint from their 911 fan and getting that polished aluminum look. Mine will be off once I get the spanner wrench today. Any ideas on getting that look?

Thanks,

Ron

 

There is really no problem in getting that look , it is just keeping that look that could be a problem. It is magnesium and there aren't any produts I have found that will keep it clearcoated without turning a milky colour. Any way there is a thread here about it already, search for fan refinishing on this forum .

 

This is mine after several hours of sanding and polishing. Started with 180 grit and worked my way to 1200. The housing is powder coated. That is another story all together.

 

I"ve polished my fan...ONCE!...It lasted a few days and the finish went to hell in a handbasket...But.. I believe there is clear powdercoating available which would probably do the trick..If not have it shot with clear epoxy paint.

 

I've never heard of any type of finishing that lasted on these fans. It might be best just to get it bead blasted and keep the original look.

 

My hand polishing typically lasts 3-6 months. Fairly easy to redo it at that time. I typically wait for a good F1 race on TV, pull the fan and start polishing. By the time the race is over, I've got the shine back again. Not much effort at all after the first time.

The magnesium will not hold the shine long term. There is no easy coating that will stay on the magnesium without some peeling. I contacted a magnesium manufacturer some time ago on this issue. Here was the response to my question about polishing magnesium. Note in particular his instruction not to use wire or abrasives containing iron.

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The short answer to your inquiry is that there is nothing I know that will give you that “polished look” on magnesium for the long term. This is the same issue people have for polished magnesium wheels. If you “polish” magnesium and simply apply a clear coat, the clear coat will delaminate (turn milky) from the magnesium at sharp edges and stone damage sites in even quite mild (humid/wet) conditions. This is because of the following factors –

Polishing with certain abrasives can contaminate a magnesium surface with cathodic (iron containing) impurities. This has the effect of further increasing the corrosion rate of magnesium alloys and aggravates the situation. Safe polishing media for magnesium would be high purity aluminum oxide, silicon carbide, glass or diamond. Do not use emery powder. Never use a wire brush to “clean” magnesium components.
Magnesium is an alkali metal and requires a conversion coating to be applied before painting. The conversion coating will passivate the magnesium surface and improve paint adhesion. This will slow or prevent delamination of the paint under corrosive conditions. All the best conversion coatings for magnesium are colored and most contain chromates. The “best” available conversion coating that would maintain a “shinny” finish is known as the # 21 Chemical Treatment (If you send me a fax number I can copy you with the chemical formulation which does contain hexavalent chrome compounds).
Magnesium is an alkali metal and epoxy based paints are preferred. Epoxy based paints suffer from UV degradation so should not be used as a top coat. Its probable best to apply a clear epoxy primer followed by a clear polyurethane for the look you are after. Cellulose paints on magnesium behave poorly.
Don’t know if this will help you – why not chromate the fan assembly using one of the better chromate treatments, rinse, dry the chromate film between 110 to 120 C, then apply a silver base/clear coat system.

 

Diamond,

You must have a lot of time on your hands! I may just have my buddy that does Powder Coating on wheels paint it for me. Beautiful job.

Thanks,

Ron

 

I did something similar to diamond... I would worry a little bit about paint. becuase if it starts to come off it will look bad and that is harder to fix than repolishing..

 

Ron,

Thanks, just waiting for the machinist to get engine parts done so I can get the engine back together. Haven't decided what I am going to do to protect the fan. The fan housing was a bear to get the powder coating like I wanted it. It would outgas and black spot the color I was doing. Finally found a Dupont outgas forgiving powder that solved the issue. I stripped the fan housing twice after the powder outgased each time. Guess third times the charm.

 

Hey Michael, How many beers did that take ya ? Looks great! Did you do the PC on the housing yourself...if so, nice DIY job also. Couldn't you put a clear PC on the fan to keep it looking that way?

Keith
'88 CE coupe

ps: BTW, if you have any fan tip/housing clearance issues once you mount the altenator (like I did), you might need to sand some of the PC from off of the rearmost (actually, the bracket side towards the front of the car) inside 1/2" of the housing (if that makes sense). My fan would spin freely until I tightened the 6 nuts holding the alt on all the way down. It was the thickness of the PC on that portion of the housing that was pulling it 'caddywompous' (I just like that word), and not the fan tips, etc. that many assume is the issue. I realize you don't have any PC on the fan tips (like those of us who went the PC route on the fan), but you may potentially have an issue. Looking Good!

 

Beautiful work. Now I see what they do in South Dakota when the snow is flying....


dan

 

Dave at TRE does a great OEM finish on the fan, fan housing, and strap/hardware.

The price is reasonable. Looks just like new when you get it back.


TonyG

 

Keith,

Lots of beer! I did all my powder coating. Work has a gun and large oven. Everything went well but the fan housing. It would out gas and black spot the color. Stripped the housing twice with aircraft stripper and bead blasted before I used a out gassing friendly primer powder coat for a base and then applied the color. It will get one more coat of clear yet and I am planning on trying the clear on the fan. A little gun shy of working with magnesium after the housing. I taped off the area were the fan mounts on the housing. Don't know what I will do next year during the winter. Possibly the suspension?

 

Nice DIY job! Just for clarification, when I had my clearance issue, it was caused by the PC that was on the inside 1/2" portion of the housing that's perpendicular to the 6 holes. My fan would spin freely until the final turn or two of the nuts that hold the altenator on. Not saying that you'll have an issue, but if you do, that might be a place to look at first....it really had me scratching my head for several attempts. Now get that engine back in...it's summertime and time to drive

Keith
'88 CE coupe

 

Man that must have been a paint o get back off . I hear that powder coating is great until you have to remove it ..