BBS Sepang rims are a three piece unit. The inner rim, the trim ring and the centre section, all tied together with titanium bolts which have a habit of snapping if disturbed. A gasket or seal of some kind prevents air leaks. Damaged stainless trim rings often get over painted in matching silver paint when they suffer curb rash. My wheels had already received that treatment.
The prime reason for re-working the rims is to address corrosion issues. Bubbling paint did not help visual appearance. Last year I had all wheels off the car to deal with some quite severe corrosion on the inner rims. On one wheel I probably removed over 70% of the paint due to rampant corrosion and severe break-down of the paint finish. A fine garnet flappy disc was used on a grinder to remove the damaged paint. Paint edges were flatted down, hydrochloric acid was applied to neutralise pitting corrosion and then etch primer applied to form an adhesion bond to the cleared back metal. This was over-sprayed with several coats of silver paint. Inspection a year later reveals this work to have been successful.
So this session has been to deal with the outer sections of the rims. Corrosion again was the reason for once again beginning another maintenance session. As you will see from the images, this rim certainly needed some attention. Just the one rim presently re-worked with the other three rims also needing rather less work than this particular example. The work shown here took nearly six hours and is slow and fiddly. Nowhere near as easy as with the Custom rims which I`ve previously dealt with. The brown/green paint is aircraft grade etch primer which was flatted down prior to grey primer and silver spray being applied. The colour is rather grey/blue compared to OE. I`ve yet to decide if I should re-spray with a different paint. At least this rim looks less of an eye-sore than it did.
I`ve successfully refurbished 19" Custom five spoke rims previously myself, but they are one piece and any paint work preparation is quick and simple. The 20" Sepang units though are another matter. More spokes, more awkward details, more corrosion and loads of masking. The bolts require half inch diameter masking to be cut from a roll to ensure paint isn`t applied to the bolts.
Mike
