Ok, I’ve got a way to cut metal and paste it back together. 50% of my practice welds on thin walled tube aren’t burning through. I’m ready to build an odd bike. Now what?
I can see how bikes are built, I’ve got a vague notion that everything has to line up, but going from zero to bike is a little bit daunting. Enter Brad Graham’s book,
Atomic Zombie's Bicycle Builder's Bonanza. His SpinCycle, the simplest plan in the book, looked just challenging enough.
The main body being built out of square tubing is the main advantage of the Squirrel/SpinCycle. It's easy to cut and weld. With the slapped together drive train, you will get experience with bottom bracket and chain work and the head tube teaches you all about steering. After being walked through component assembly by Institute Regular Eric Bailey and taking apart the Squirrel a couple of times, I have no hesitation tackling any job on my store-bought bikes.
The critical angles on a Squirrel/SpinCycle are all 90 degrees, except for the head angle. Brad’s instructions for an approximately 45 degree angle are wonderfully vague. Don’t get attached to that approximate attitude for head angle, fork rake and trail, the more your creations are like bikes, the more predictable and solid steering performance you’ll need. There’s a whole lot to learn, as my friend Al Oldmark says, “The master frame builders, they didn’t really get it right until the third or fourth bike.”
The adaptation I added to the Squirrel/SpinCycle was a rear wheel drop out, this allows for moving the drive wheel to get proper chain tension. Very important but not a drop dead complete solution.
I tried some cheap casters, with just a central axel and cheap rubber. Bad idea. They make the bike slow. Shopping carts have the perfect casters; tough tread and ball bearings. Brad suggests finding a shopping cart at the dump, but you cannot remove scrap from Seattle dumps. You could get a busted up cart at grocery stores, but all my local stores lease their carts. I couldn’t bring myself to steal wheels of the abandon carts in my neighborhood (I’ve got the pickup, so I’m generally the one who returns them to the stores). So I bought a pair, at where else? Seattle Casters, $11 each.
