Anyway, yesterday I left work to find the sunvisor of my SL draped pathetically over the steering wheel. The $*&%#@ plastic clip had broken, the male bit that's part of the visor itself. Perhaps it broke spontaneously, perhaps it had help. Regardless, I know that: 1) you can't get that little plastic bit separately, but only with a new vi$or; 2) no one's ever been able to glue one successfully; 3) one new visor is expensive enough, but it wouldn't match in color, so I'd either have to purchase two (!) or paint them both, again, to match.
Ugh. I was not in a good mood going home, trying to hold that visor out of the way so I could drive.
I removed the clip by first prying the broken-off bit out of the socket. Carefully! You don't want to crack the plastic socket too. Then, I removed the tension screw in the sunvisor itself, and then swung the visor back and forth around its pivot rod while pulling the visor along the rod. The idea is to slip enough of the rod out of the visor that the other half of the clip is released. That all worked well enough, I then had two broken clip halves in hand.
I have a couple of sunvisors from the other SL, so I could nab a clip from one of them. But, they're even older than mine, so old that they had partially decomposed—they are like sawdust-filled socks wrapped around a coathanger. (That's why they're in a box and not on the car.) Didn't bode well for the plastic clip's holding up. And, they're completely the wrong color.
This morning I had another idea though. Recently I had bought a plastic welder from Harbor Freight. Nothing fancy, it's just a giant soldering iron with a sleeve around it that compressed air blows through. This makes a jet of very hot air. You use it to melt plastic, generally using a filler rod to add a like plastic to a joint. I've used it to make a real mess out of some plastic, there's obviously a trick to it. One trick is not to have too much air blowing through it, otherwise it sprays molten plastic all over!
But, I had little to lose here, even though I had no filler material. So I fired the thing up and pointed it at the clamped-together clip. This plastic melts nicely, it gets all runny like wood glue! I was able to make a puddle on one flat face across the crack. It takes some finesse to melt just enough and not too much so that you make a shapeless blob. When in doubt, back off! I let the piece set up a bit, and then turned it over and repeated this on the back. Waited a bit, and then I fused the two remaining edges. Then I went back over it all again. The idea was to fuse the crack together, without seriously deforming the overall shape. I think I did fairly well. You have to let the piece completely cool before reassembly, so that it's not soft anymore.
I reassembled the sunvisor and popped the clip back into the socket. It held! I can adjust the visor as I did before. I have not tried to pull the visor back out of the socket, so I don't know just how strong the repair actually is. I never do this normally, though, and I see no need to tempt fate now. At the moment I am happy, and I want the moment to last!