Centre caps
 

The Audi centre caps seem to suffer a lot of corrosion around the outer ring.
http://i219.photobucket.com/albums/c...h_P1040936.jpg

So I decided to have a look underneath to see what could be done about it.
Sadly the only way to remove the ring means destroying it as it is crimped on the full circumference of the cap.
That ruled out any chance of refurbishing. All is not lost though as the area underneath the ring is painted the same as the rest of the cap face and with a bit of spit and polish looks not too bad.
http://i219.photobucket.com/albums/c...h_P1040937.jpg

Now I can have a choice of plain centre cap rims
http://i219.photobucket.com/albums/c...h_P1040938.jpg

or polished...
http://i219.photobucket.com/albums/c...h_P1040939.jpg

centre caps
 

I tried taking one of these apart and failed miserably....wanted to respray the the four rings and the outer bit...but I couldnt work it witout breaking it....if anyone can shed light on this would be great...

The 4 rings are made from plastic and are held in place with 2 pins and 4 tabs, the tabs have one way lugs on them and the only way to remove them would be to break the tabs, they would then have to be glued back into place.

I found one of those exact caps by the roadside the other week walking home from t'pub.
Picked it up thinking someone here might want it for a spare.

But when I cleaned it, as above the outer shiny ring was badly corroded and the Audi rings a bit tatty.
I too looked at it carefully to see if it could be dismantled and "sorted" but found the same challenges and binned it.

I was surprised how many carefully designed and made components were in it though, I was expecting a much simpler object than I found. :Confused:

Decided to have a go at removing one of the outer rings without mangling it.

There are 3 tabs which require straightening
http://i219.photobucket.com/albums/c...h_P1040940.jpg

http://i219.photobucket.com/albums/c...h_P1040944.jpg

Then you need to un-crimp the outer edge of the rim
http://i219.photobucket.com/albums/c...h_P1040945.jpg

and with some gentle persuasion the ring will come away from the backing
http://i219.photobucket.com/albums/c...h_P1040949.jpg

The amount of crud inside is a poor design, salt water getting into the back does nothing else other than assist the corrosion
http://i219.photobucket.com/albums/c...h_P1040948.jpg

http://i219.photobucket.com/albums/c...h_P1040947.jpg

So I decided to try and clean a small section of the ring
I started with 400 grade wet & dry then 2000 grade
If you zoom into the image you can see that even after removing the lacquer (light silver/white sections in the image) and etching (light grey sections in the image) and rubbing away at the bare aluminium (dark sections in the image) there is still lots of pitting which would be difficult to remove.
http://i219.photobucket.com/albums/c...h_P1040950.jpg


My conclusion, either remove the rim as per picture 2 on the first post or buy new caps



If anyone has a spare cap which is corroded and they don't require it I will happily take it off your hands as I only have 3 +++


Checking the 4 rings logo it looks like it is wedged in with tapered pins and I suspect with a little force should be removable
http://i219.photobucket.com/albums/c...h_P1040942.jpg

Good news Ranj, the centre rings do press out +++

Using a small blunt instrument press the tab using a steady even pressure
http://i219.photobucket.com/albums/c...h_P1040951.jpg

until it is level with the main body,
http://i219.photobucket.com/albums/c...h_P1040952.jpg

Do this with all 4 tabs, no need to bother with the round pin as it is for locating only and just slides through.
Then turn over and ease the rings out from the main body
http://i219.photobucket.com/albums/c...h_P1040953.jpg

Get the rattle can out and paint whatever colour you want +++
http://i219.photobucket.com/albums/c...h_P1040954.jpg