Every so often, you find yourself in need of a unique tool to fit the situation. Most of the time, such a tool can be bought. Though, because of their limited need, stores must sell these for a higher price to average out the lesser demand. Compounding this fact, no one wants to pay a lot for a tool they'll only use once.
I've collected a list of all the one-time, single-serving tools from recent memory. If you have similar single-serving tools, I'd like to see them.
(1) An improvised headset press.
I needed to install the bearing cups to a 1-1/8" threadless headset on the bicycle I was building. But, I was only going to do this one time, so I didn't feel like buying a tool, even if it only cost $20.
My solution was this. A 1/2" screw is used to push two soft plastic plates together. These, in turn, push the cups into the headset. The plates were made out of some plastic from an old cutting board.
For best results, stick the cups in the freezer for half an hour--they will contract slightly and fit more easily.
(2) An exceptionally long allen wrench.
Have you ever needed a really long allen wrench? Well, I did when I was constructing the drawer set for my new lathe. Local hardware stores didn't sell allen wrenches this long--at least not in metric--so I built my own.
Take a normal allen wrench and hacksaw-off the bend. It's hardened steel, so it will mess up your blade--use a worn-out blade. Take a length of 3/8 round steel, bore a 1/4" hole at one end, at least 1/2" deep. Insert the hex bit, and then weld it on to the rod.
Also, bend the far end of the rod, or weld on some sort of handle. I used my lathe to turn the rod down a bit, making it easier to bend.
Ultimately, this 5mm wrench will reach more than nine inches deep into a 1/2" hole.
(3) An easy way to measure angles.
When I moved into my apartment, I immediately devised a plan to build an long shelf above head level in the hallway. Because this apartment had been sliced off of a single family residence, it had an awkward hallway in the wrong place. The hallway space seems like a significant fraction of my apartment, and without the shelf it would all be lost.
The problem was that the walls in this hallway didn't meet at right angles. It's very ad-hoc, with three turns at angles around 13-31 degrees. I needed to measure these angles or the wood wouldn't meet right.
Sure, protractors are cheap, but one wasn't available when I had my inspiration.
I built this out of some 1" extruded aluminum angle-stock and a small machine screw, nut an washers. The trick? A hole is drilled on each bar, 3.5" from the pivot point. For any angle, the two holes and the pivot point make an isosceles triangle. Then, if I measure the distance "h" between those two holes, I can calculate the angle between those bars as 2 * sin ( h / 7 ).
The shelves, by the way, look great and line up perfectly.
So, anyone else have single-serving tools to share?