continued from above
LEXAN SIDE REAR WINDOWS
One thing I didn't get this time were the weights on the glass rear window or side windows vs the Lexan bits. I did get the weights on the HARD Motorsport and OEM E46 rear side rear windows
in this July post on the E46 330 TTD car, which I copied below. The Five Star bits weigh almost exactly the same but the HM bits are much easier to mount (with their optional install kit) and come with a black outline vinyl border pre-applied to the inside.
The side windows were installed first. Like most race car parts these come with no instructions - you're expected to know what you are doing.
Ryan began by marking the outer perimeter with two lines that corresponded to part of the "black border" that would be added later as well as a centerline for drilled holes. These were marked using a compass and a Sharpie, which you can see below at left. The outer protective film was left in place as to not mark up the actual Lexan plastic.
None of the factory mounting hardware was re-used. Holes were drilled equally around the perimeter of the glass that would land in the sheet metal surround of the window. Then the holes in the windows were transferred to the body and those were center punched and drilled.
M5 nutserts were installed into the sheet metal surround for each window then countersunk stainless Tinnerman washer and countersunk stainless bolts secured the window in place. This makes for flush mount, corrosion free hardware. The factory black drip rail trim was then reinstalled.
LEXAN REAR WINDOW INSTALLATION
The rear window installation followed the same techniques: marked and drilled Lexan, transferred holes and drilled sheet metal, added M5 nutserts, then Tinnerman washers and countersunk M5 bolts.
Many of you readers have seen us install and use these threaded inserts or "nutserts" on many projects. We tend to use metric splined steel nutserts in M4, M5, M6 and M8 sizes, like the one shown above left. These add a threaded hole to sheet metal that is "blind" or hard to access on the backside. There are also versions for use in plastic or fiberglass panels as well. If you can work a blind rivet gun you can work a nutsert installation tool (above right).
This is how they are installed... you drill the appropriate hole (there's a chart), install the nutsert you want with the correct "grip length" (there are longer nutserts for thicker panels), then use the tool to squeeze the insert and expand the back side behind the panel. Now you have a threaded insert that is secured in place. Sure, you could install welded inserts, but that's a lot more work. We tend to use those on thicker metal, if we cannot drill/tap it for some reason, or if we need a much longer threaded length or more strength than the nutsert can support.
Like Ryan did on the same exact brand of rear window on my E46 330, we will go back and tape off then spray paint the border on both the side and rear window on this E46 M3 at a later date. This makes the windows look a lot less "race car" and hides the visible sheet metal underneath.
continued below