all in the preparation.

So I've been learning about machining, that strange process where we take our world full of bumps and flaws and irregular forms, and turn out a million identical parts with almost arbitrary precision: 0.0005", half the thickness of a human hair, is achievable on amateur home equipment. And the hobby budget has opened up somewhat, paving the way for me to be cursing at different things than I curse in my day job. With the dog, and no garage, there hasn't been a place to set up any tools, let alone tools that create piles of razor-sharp shards of metal...until now.

With the garage gone, we had a dense pile of crap sitting out under tarps, and a different, sparser pile of crap inside a U-Haul storage trailer (which, for the record, is every bit as shitty as U-Haul). Our new, well-built shed was still a month away, and the shed people need the whole backyard to work in, and we don't want a permanent building anyway...

I watched some YouTube of a master carpenter who carefully built a full wood shop into a utility trailer that he drove out to job sites. Other examples came to mind, like folks who make the rounds doing repairs and tweaks at race tracks. Or the main repair service for old Linotype machines.

(Linotype aimed to speed up typesetting for newspapers, back when everything had to be printed on paper. Picking out individual letters and spacers is exactly the pain in the ass you'd imagine, so Linotype and its peers built a machine that looks like a small church organ, slightly larger than my car. The operator types out a line and hits the equivalent of Enter. That typing has created a mold for that entire line, and hitting Enter fills the molds with molten lead from the reservoir in the machine, casting the Line-O-Type (get it?). The lead castings were placed into a frame and used to print. When finished, the casting was melted down again.

I once wandered into a museum in Palo Alto, located in a mansion downtown, and out back, in a building that might have been stables, then was definitely a garage, there was an older guy, somewhere in his early/mid 70s, restoring a giant printing press. I love the history of technology, so I got a tour of the Linotype, and a description of his career in newspapers, and how he was the only person they could find to fix the things.)

Hmm. If I were to choose machinery carefully, keeping the weight down because a shop crane won't reach inside...if we had a shop trailer, we could solve our temporary storage and longer-ish term shop space problems all at once. In a sort of kismet moment, there was one for sale on Craigslist right there. The workbench and everything was fitted out by a master carpenter, but the trailer is made by, no joke, Wells Cargo.

So I bought a metal lathe. Don't confuse this with a wood lathe, which is also made of metal, because the most basic machinist lathe requires reams and piles of highly-specific bullshit that wood lathes don't need to bother with. Take, for example, ideas about "flat" or "level." These barely make any sense on a wood lathe, where you're cutting everything by hand anyway. If a wood lathe is twisted by 0.1", you probably won't notice, or you'll manually account for it. On a metal lathe, your parts won't be even or fit together. You need to align the lathe so it's all in a plane. How do you get a flat plane? Take 3 plates of granite or iron, mark them up and rub them each against each other, chisel or grind off the high spots, and then they'll be equally flat.

How do you transfer that plane to the machine? Take an adjustable level, make it match your flat plane, and then you have your shop's definition of "level" that you can use on the machines. It may not be "horizontal" in the sense of being at a right angle (90º) to the direction of Earth's gravity (down), but it doesn't need to be. Ships have machine shops, which obviously won't be horizontal much, so they just bolt everything to the floor, and it's fine.

The best answer to machine rigidity is always "bolt it to the heaviest thing you can find," but I have a tiny lathe, sitting on a not-really-flat workbench, in a trailer, tilted backwards so the rain runs away from the leaking part of the roof, still resting on its tires and shock absorbers. So there's some stuff to account for.

This is without having actually tried to cut a part, because I'm pretty sure it would just be a mess.

One of the things I am finding satisfying about this is that everything takes a lot of thought and planning. On any machine tool, it's not unusual to spend an hour or two of setup for an actual cut lasting several minutes. It's really cool to have tangible problems in front of me. This is all "manual" machining: most machining nowadays is by computer (CNC). But I find the same thing I've found about music, which is that there is software that really enhances the experience, but I spend my life on computers already, and I'm avoidant about adding more computer time by way of hobbies. My brain needs the break.