I've made a small amount of progress since the last post. It is, however, very satisfying to write that the first custom tool was a success.... at least the second time around.
Opening up the plastic cap pressed into the pedal crank reveals a bolt and some much larger threads
Thinking I'd be smarter than the people that sell all the custom tools for bikes, I figured I'd just use my handy little puller to get the job done. If trying this yourself, don't bother. There's too much deflection, too little grip, and not enough force to get the job done. It just made a mess of the aluminum where the fingers were digging in. No harm done though, I'll just clean it up a bit when I reassemble. Oh and YES, I did have the bolt undone. I replaced it loosely to give something solid to push against.
It's tool making time! I read about a guy that successfully made this tool from aluminum and since I have a bunch of round stock I gave it a try. Threading is a pain to set up on my machine but with a nice big undercut to run into it isn't bad to machine.
As things turned out, the tool above didn't quite thread in. I measured the pitch diameter later at work and it was right on what it should be. So why didn't it fit? I think the threading tool form wasn't quite ideal and there was a lot of tearing and such. The threads didn't look great - which is a good indication whether they'll work or not. I got it to thread in a bit but it started galling and making a mess of things so I stopped and went back to the drawing board.
No worries. CNC makes things so much easier.
About an hour of effort produced a new tool with absolutely perfect threads. Oh, and this one is 4140 HT steel. The setup was reversed from how I did it manually and I left a long stub that I could hold in a collet block to put the flats on. The external thread is a non-standard M22 x 1. The internal thread is 1/2-20 UNF which was drilled on the CNC but tapped by hand. It's iffy tapping a one-off hole on the CNC lathe with the tools I have available.
Lots of grease was added to get the most pressure with the least friction. I could have used a slightly longer bolt but, again, materials at hand. I ended up sticking a smaller SHCS down inside the hole to take up some extra space and give me enough length to pull the crank arm off the taper.
I was able to remove one side of the bottom bracket without any special tools. Really big pliers did the trick without any damage. That said, after what I found I'm not planning on trying to salvage any of the parts. I'll be installing a new sealed type as long as I can find what I need. I've been known to pedal through water that's above the bike's axles, so that's likely the cause of some of my troubles.
I still need to come up with a way to remove the nut on the drive side of the bottom bracket housing. It's really not the brightest design in my opinion. It's round with two very small flats - which don't give much to get a grip on with traditional tools. Can anyone confirm that this is a left hand thread? It would make sense and I've seen a few references to this fact online.
