In April 2011 I purchased Autotecknic CF mirror covers for my justa. Initially, I was very impressed with the fit and finish of the covers but after 2 mos the gelcoat started to bubble on top of the mirrors. Although I bought the mirrors from an eBay vendor I contacted Autotecknic for replacement under their 1 yr warranty. After numerous emails they agreed to replace the mirrors with the following advice:

1. Wait till the mirror covers are cooled down before washing as a sudden change in temperature may alter the finish.

2. Please make sure all the gaps are free of water after you are done washing as water may seep through over time.

Doesn't seem very practical for a car that might be exposed to a sudden downpour while sitting in a hot parking lot.

I think the problem may be in manufacturing. After the carbon fiber and gelcoat are applied to the covers, the extra gelcoat is sanded off the edges of the covers exposing the raw carbon fiber. These edges are not visible after the covers are installed on the car. It's my theory that water is wicked into the carbon fiber and under the gelcoat and this eventually leads to bubbling in the gelcoat where it's exposed to direct sunlight. Accordingly I've coated the edges of my new mirrors with black Krylon to keep the water out. Hopefully this set will hold up better than the originals.

 

Well sounds like you might want to add another gel coat or another clear coat for the added protection. There is nothing wrong with ever doing that.

 

I briefly considered trying to put a fresh film of gel coat on the edges but the gap between the mirror cover and the mirror housing is only about .025" and I didn't think I could get the fresh gel coat on that thin without having to sand the edges all over again. I'm hoping 3 thin coats of Krylon will seal out the moisture.

 

Go for it.

 

does the oem mini jcw ones require this type of care?

 

No

 

Final chapter: My replacement mirrors bubbled just like the original set. The finish on top of the mirrors has dimples on it like a golf ball. I think what is happening is that the gelcoat or resin topcoat is shrinking with age and revealing the imperfections under the gelcoat. After the hassle of the first return, I'll just keep them and try to level the finish by wet sanding and polishing the surface. Bottom line: Don't buy Autotecknic carbon fiber products.

 

How much did you pay? There's a reason why most high quality Carbon Fiber parts are high dollar. If done right, then it will last, but there's a lot of lower quality out there.
Hopefully you can wetsand them back to an acceptable level.

 

It's been about a year since I got the first set and I believe the price was about $140 for the pair. The bumps wet sanded off just fine (the gelcoat seems very thick). As long as the gelcoat/resin doesn't shrink any more I should be OK.

 

1) There is no gelcoat, it's clearcoat.

2) by its very nature, neither the carbon fibers nor the epoxy resin matrix will absorbe water or wick water.


The probable reason its bubbling is they did a crappy job of cleaning the part b4 they applied the clearcoat. Or the didn't let the part offgas enough before coating. Doesn't matter either way. There is a reason cheap carbon parts are cheap...

 

I have all the OEM JCW CF parts on my car. I had the JCW CF scoop but swapped to the M7 Vortex II hood scoop in CF. The M7 part is holding up after 2 years but the quality of the M7 CF scoop is no where near the quality of the OEM.

Same thing for the M7 C-wing I had on my car for 1 year. Quality was just OK.

THE OEM parts are expensive but you can find deals here on the NAM marketplace and on eBay.

I did not pay retail for any of these parts. It did take a long time to get them all though.