I'd never done this before and previously disliked fiddling with derailleur bikes (as opposed to internal gear hubs), so the whole thing was a learning process. Above, the new rear derailleur has been installed. The old one, which I'd never actually looked at before, was caked with dirt. I couldn't tell if it started malfunctioning because of the rusted, tired spring or because it was full of dirt. My hands were too dirty to take a picture of that at the time.
I put the front derailleur on as well, but I think I'm missing a part to retain the cable housing because I couldn't figure out how to link it up. I thought of making my own out of spare parts laying around, but had none that could work well enough. I did mock up what I could and I actually look forward to installing the cable some day. For now, the front derailleur sits on the bike but out of the way, as a reminder for me to get it working.
I unwrapped the left handlebar to try to get the brake lever off and maybe put a new cable in, but the steel bolts had corroded to the aluminum part and may be frozen there for eternity (or until I come with the angle grinder). Also, the bar tape was originally red. That was a surprise.
After six hours of working on the bike and doing my actual job, I hopped on and rode home. The new chain and derailleur were so amazingly quiet and smooth; everything spun surprisingly little effort ... none of the parts are actually good, but the ride had become ten times better.
I brought the bike in to do more fine tuning and used the chance to take some better photos. As you can see, the derailleur I installed has a long cage as opposed to the short cage that it came with and it seems that the chain I used is a few links too short, even though I didn't take any out. I raised the front derailleur and turned it out of the way since its default relaxed position is for the smaller chain ring. Since the somebody replaced the original 5-speed rear cassette with a 7-speed some years ago, the chain rubs the large chain ring if I use the smaller sprockets with the small chain ring.
Here is my proudest creation: the one functioning brake. Out of all the cable segments that I had, I couldn't make one continuous, good strand go all the way back. I was actually kind of worried that I wouldn't be able to get home until I got this idea. The rack I used had two of these metal pieces to be secured to the bike and since I could only use one, I used the other to join the brake cables. In other words, the piece of metal is actually part of the brake cable. It looks horribly janky, yet works wonderfully well. I actually have a working brake for once (the brake work done in the previous post provided only slight deceleration).
The slot in the rack stay was too narrow and since I didn't have power tools, the only thing I could do was try to force the open end onto the brake bolt. Upon tightening the nut, I heard a bang and discovered that the two "prongs" had exploded apart and out of the way of the nut, so I just did my best to fork it over the assembly. I won't be carrying heavy loads with this, anyway. Also, the brake pads have been slanted on purpose. The caliper I picked up was wide enough to clear the fender (which itself was meant for wide tires), but the slot for the pad didn't extend up far enough to even touch the rim. I "solved" this problem by tilting the pads upwards so they would at least clamp onto the wheel.
In the above photo, you can see how I cut out parts of the fender so it could fit between the fork without squeezing. My roommate let me use his Dremel to do it yesterday. I filed down the area between the brake calipers as well so they could clamp down but later took the whole brake out since all it's going to do for now is get dirty.
The front brake caliper is visible here but I removed it after this set of photos. The bolt thread is stripped and can't be removed without releasing the springs, so I might have to look for another brake (oh wait, the lever doesn't even work). The bike will probably have this asymmetrical look for a while since I'm still trying to decide what to do about the front brake.
So yeah, over the last few days, I've added fenders, a rack, functional brakes, a new chain, and front and rear derailleurs. The only things I had to spend money on were the chain and bunch of nuts and bolts, most of which ended up going unused after trial and error. I have mixed feelings about all the extra weight (hence the first sentence of the post) and complexity, but I'm happy that the bike is more functional now.
Are those flies or birds?