Fan Shroud Powdercoating

[SGKent]

[jtauxe]

I had mine sandblasted and left it at that.

_________________
John
"Travelling in a fried-out Kombi, on a hippie trail, head full of zombie..." - Colin Hay and Ron Strykert
http://vw.tauxe.net
1969 Transporter, 1971 Westfalia, 1976, 1977, 1976, 1977, 1971, 1973, 1977 Westfalias,
1979 Champagne Sunroof, 1974 Westfalia Automatic, 1979 Transporter, 1972 Sportsmobile, 1973 Transporter Wild Westerner, 1974 Westfalia parts bus, 1975 Mexican single cab *FOR SALE*, 1978 Irish 4-door double cab RHD

[orwell84]

I made the mistake of thinking my fan shroud was aluminum and buffed it to a near mirror finish. It looked fantastic for a couple weeks.

I guess I could keep this finish if I polished often, but it’s a bit much for a non show car. Someone suggested a one time rattle can lacquer clear coat. It would have to be redone every so often but would clean off easily with thinner.

[SGKent]

Gibbs oil will patina it to an even dark color if you clean it first. Some folks use that. Others clear coat right after media blasting. Mag will oxidize under the coating at the edges and scratches.

_________________
“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[Clatter]

I have been down this road so many times now..

Take-home message, is that none of the treatments will last if your bus is used hard in all kinds of weather.
If your fan shroud still looks good years later it means you aren't driving it enough.


In Phoenix, a polished mag fan shroud would stay shiny for a couple of years.
I kept it up a bit now and then, and, yes, this was due to the vitamins we were taking at the time.
Once i moved to the SF bay area the shiny went away in just a few days.


That kicked off my never-ending quest to get a shroud to look nice..
Remember:
1. The mag is porous.
2. A used shroud spent it's life soaked in oil.

Hence, different types of tanks were tried to get the pores free of their oil;
Both a normal petroleum solvent-based 'soak tank' as well as one of those dishwasher-like soap parts washers.
Also put it in the oven to bake, ran it thru with fresh soap, etc.
It always gets blasted before powder coating as part of the process.

Nothing lasted long-term.
Powder-coat would eventually start wrinkling and lifting, as would paint, even after multiple tries with different etch primers, epoxy, etc..


I found a place near SF that will do alodine.
After the tank/bake/tank/blast routine i plan to try that.
Another I'll be trying is wrinkle vein powder.
My hope is that it will hide the lifting/crazing that inevitably happens..


Until then, i just do like Steve - paint, and touch up.

Now that i drive my bus a lot less, it should stay looking nice for many years.
_________________
Bus Motor Build

What’s That Noise?!?

[raygreenwood]

The Alodine.....willook good for a while.....but bear in mind.....Alodine IS a sacrifical coating. Its a conversion coating with a chromate.

Its designed ....not to look good....but to seal the magnesium to prevent if from starting to oxidize. Its to prevent corrosion, especially on sircraft parts. Its designed that the Alodine will oxidize FIRST over a long period of time to delay oxygen from coming in c9ntact with the magneaium and starting its oxidation process. Ray

[78BusGA]

Given the availability of the skills of some of those in the forums, I'd not be unhappy to have the shrouds cast in alternative metals. Aluminum, brass...

Heck, 3D print a set from high temp materials.

Lots of new tech is available to us now... Don't really have to let the Magnesium thwart a nice finish if enough put their hands to it.
_________________
Few will understand the passion and majesty, among the nuts and grease.

Tom H.

My '74 Super 1303 thread - https://www.thesamba.com/vw/forum/viewtopic.php?t=764902&start=60

My '78 Kombi Bus thread - https://www.thesamba.com/vw/forum/viewtopic.php?t=769385&highlight=

'72 Superbeetle (retired), '78 Bus Kombi 2.0FI, '74 1303 Superbeetle

[raygreenwood]

[78BusGA]

Are there other metals that are more molecularly friendly for bonding with the magnesium in a plating process?
_________________
Few will understand the passion and majesty, among the nuts and grease.

Tom H.

My '74 Super 1303 thread - https://www.thesamba.com/vw/forum/viewtopic.php?t=764902&start=60

My '78 Kombi Bus thread - https://www.thesamba.com/vw/forum/viewtopic.php?t=769385&highlight=

'72 Superbeetle (retired), '78 Bus Kombi 2.0FI, '74 1303 Superbeetle

[orwell84]

The worst thing I ever used was POR15 clear. What didn’t peel off with use was a bitch to get from with sandblasting.

For me, I think the best option had been the polish I did. It will of course not last but I’m good with shining it up with some Mother’s when I’m in there doing other stuff and just cleaning up.