Tweet
I ended up with an OEM Evo 3 rear spoiler, for free. The spoiler was white and had a few long cracks. In the center, and at each end. Probably caused by some flex, not the usual contraction/expansion. Having nothing to do this weekend, I decided to strip it from its paint and see how come that sucker was so heavy, and what caused the cracks. I bought two quarts of furniture paint stripper, a small horsehair brush and here we went.
I first removed the flipper from the main wing and generously apply several coats of stripper on the main wing. After the second application, the first layers of paint started to peel off byt them self, without requiring any work from me, except laying more qand more stripper until I reached the final coat. There were 4 coats of paint (and 4 coats of primer). I let the paint finish flaking and harden overnight. I stripped the flipper, layer per layer, used a razor blae to remove some of that extra hard gelcoat, softened by the stripper. With some running water and hard scrub, I finished removing any paint and primer stuck on the flipper. I little bit of 600 grit and water finished cleaning up the flipper. He is how I spent 4 hours of my day.
It was instructional as I finally understood what was that "fiber reinforced plastic" the flip is made from. Imagine a dark resin, withy full of white hair. The flipper is now ready to be primed and painted. I even managed to leave the part number and logo untouched. Just like new.
The second day, I went back to the main wing and sanded it with an electric sander and some 220 grit. The paint that is usually tough to remove is now extremely brittle and flaky. I spent the 3 next hours removing whatever paint was left, with some water and a block sender, leaving a perfectly smooth finish. The main wing is very soft when yo press it. Right in between rubber and plastic. It is black all around, but the under part is a clear "fiber reinforced plastic" in wich 16 inserts have been cast. I do not undrstand why BMW who was dealing with shops like "Die Weithje" could not come up with a much lighter composite rear wing. If you have ever weighted a CF rear wing from MA Shaw or any other supplier, it is feather light, so much that the trunk opens by itself...
The reason why those rear OEM wing crack all the time, is propbably because the core itself is soft. Add 20 years of contraction and expansion, half a dozen of stiff paint coats, and you have a recipe for major cracks. In my case, the paint had badly cracked, but the core itself is perfect. I spent all in all 7 hours doing the job, prepping the wing so that my bodyshop can put a sealant, milk coat it and paint. I saved them the kind of job they hate to do, and I made sure it was done perfectly. I hate when coats of paint accumulate, as it makes a opart brittle and easy to chip. Picture of the stripped wing soon.
I first removed the flipper from the main wing and generously apply several coats of stripper on the main wing. After the second application, the first layers of paint started to peel off byt them self, without requiring any work from me, except laying more qand more stripper until I reached the final coat. There were 4 coats of paint (and 4 coats of primer). I let the paint finish flaking and harden overnight. I stripped the flipper, layer per layer, used a razor blae to remove some of that extra hard gelcoat, softened by the stripper. With some running water and hard scrub, I finished removing any paint and primer stuck on the flipper. I little bit of 600 grit and water finished cleaning up the flipper. He is how I spent 4 hours of my day.
It was instructional as I finally understood what was that "fiber reinforced plastic" the flip is made from. Imagine a dark resin, withy full of white hair. The flipper is now ready to be primed and painted. I even managed to leave the part number and logo untouched. Just like new.
The second day, I went back to the main wing and sanded it with an electric sander and some 220 grit. The paint that is usually tough to remove is now extremely brittle and flaky. I spent the 3 next hours removing whatever paint was left, with some water and a block sender, leaving a perfectly smooth finish. The main wing is very soft when yo press it. Right in between rubber and plastic. It is black all around, but the under part is a clear "fiber reinforced plastic" in wich 16 inserts have been cast. I do not undrstand why BMW who was dealing with shops like "Die Weithje" could not come up with a much lighter composite rear wing. If you have ever weighted a CF rear wing from MA Shaw or any other supplier, it is feather light, so much that the trunk opens by itself...
The reason why those rear OEM wing crack all the time, is propbably because the core itself is soft. Add 20 years of contraction and expansion, half a dozen of stiff paint coats, and you have a recipe for major cracks. In my case, the paint had badly cracked, but the core itself is perfect. I spent all in all 7 hours doing the job, prepping the wing so that my bodyshop can put a sealant, milk coat it and paint. I saved them the kind of job they hate to do, and I made sure it was done perfectly. I hate when coats of paint accumulate, as it makes a opart brittle and easy to chip. Picture of the stripped wing soon.
Comment