I highly recommend reading through photoelectrics thread. He does a really good job with prep work. Of note: prep work is 90% of a paint job. A rushed prep will always result in a bad paint job.
https://geekhack.org/index.php?topic=47490.msg1012469#msg1012469Sanding the rubber coating off of the early QFRs was time consuming, I am not sure how the tk compares as far as thickness. I did a few QFRs myself and had good luck with 220 grit to get the majority of the coating off, then going over the whole thing with 400 grit to get it all smooth. Once you are done sanding, wash the cover in the sink with soap and let it completely dry. Once it is dry, try not to handle it as it will leave oil from your skin and potentially ruin your finish. Several light coats of primer (you don't have to have lay down so much primer that you completely coat the case with each layer). Once the primer has cured for the recommended time on the can you can do a light sanding with the 400 grit to get rid of any high/rough spots. Wipe off any dust and you are ready for color. Several light coats of color with a small amount of "tack" time in between, then one final thicker coat to try to get the whole case to have a shiny look - be careful not to put down too much in one spot or it will run. Let it dry for at least 24 hours before handling it. If you are unhappy with the finish, you can sand with the 400 grit again and lay down a few more coats. Again let it dry for at least 24 hours. If the finish is good, you can either leave it as is or put a clear coat on it. Do not put wax or polish on it for the first week as the paint is still curing (especially critical on light colors). After that first week, you can polish and wax it and be done with it.
