I don't know if the other commenters are ignorant or are being facetious.. but the reason is because they'd probably be doing that operation on the mill, not on the lathe.
For anyone else, youd definitely be alright with making the hole in the bolt "before tightening it", as that's how castle nuts work.
Typically you tighten to spec, and then continue to tighten until the next slot is indexed correctly.
I once had an argument with a so called safety director after he tried to tell me I had to wear gloves while working on a lathe. I told him I absolutely refuse. He threatened to write me up. I told him to go right ahead and then I'll go over his head and probably get him fired for insisting I do something unsafe. Needless to say he wasn't around for long ..
As a safety director myself, I've found tons of success in my career from assuming everyone who's doing a trade knows more about it than me.
So I ask: "hey, are gloves required for that job?"
And a machinist would go, "fuck no, I don't wanna get degloved."
And I'd respond, "makes sense, thanks for knowing that; need anything from me? No? Aight, have a good day."
Someone who's been doing the job for 40 years knows what's going to get them hurt and what isn't. Some things are hard-and-fast OSHA rules, and some really are "listen to the guy who's worked that machine since your parents were in high school."
"and they reply, have you seen the Russian lathe guy video?" to which i reply GOT DAYUMM!!
side note. how the hell do you create thread pitch on a lathe? i genuinely know most of how they work and have scarcely used one. i know its usually threads per inch or MM but how do you set a tool to carve?
There are different "gear" combinations that will determine the distance the tool travels (feed) vs the number of times the workpiece rotates (speed). With the right ratio, you cut a spiral thread instead of shaving the entire surface. Hopefully an actual machinist can give you a little more detailed explanation.
You can lock the spindle and the carriage together, so every rotation the longitudional travel will be the same. You set the pitch on the machine with gears and ready to go. (i dönt know the correct english terms)
You can lock the rotation of the spindle and chuck)the thing holding the bolt, to the lead screw that moves the tool cutting the metal. There is basically a transmission that you can change the gears on to change the rate at which the lead screw moves in relation to the spindle's speed.
Wait until you learn how hard drives work by spinning magnetic plates at up to 10,000 rotations a minute and use a tiny magnetic needle head to write clockwise circles indicating the value “on” and we manage to store terabytes of information on a couple 3 inch platters that way.
That's like burning CDs right? I think that's really neat how we've progressed from making wax records to capture sound all the way to using light and magnets to store information.
Since they're metalworkers, I'm sure they're pretty precise/safe, but "building a metal shop from scrap" sounds ghetto AF. Like "for the first step, you're gonna need to harvest about a dozen carburators."
It's actually mostly casting from recovered aluminium (Not cans. Apparently not very good casting alloy). The bloke who wrote it back-engineered the history of powered metalworking tools and effectively wrote a speedrun on "hand tools to milling machine".
The fascinating stuff is how he came up with ways to "steal precision" at several steps. Giving up precision in one unimportant area to get more precision in a key dimension.
Like boring out the axis for the lathe head stock. You want it to be aligned to the lathe bed as accurately as possible. Even quarter a degree misalignment is going to be an issue.
So what you do is set up a temporary axis that is going to absolutely be misaligned. Then you mount your lathe head backwards (where the tail stock would go) and push the head onto the temporary boring rig. Your lathe axis is going to end up with a slightly elliptical hole, but it will be aligned.
It couldn't fly out, locked in by the T shape. I do weird stuff in 4 jaws, ive made 3 jaws hold square parts, but ive never seen anyone do this before. Over 25 years of being a machinist and still learning!
He uses the grooving tool for marking out and facing.
The feed rate is too high, he is producing a continuous chip. Also, you can see the Chip is too hot since he doesn’t use cooling.
He is just barbaric towards his tools. (Sorry for my bad English, but I had to use a translator for the technical terms)
Watching this whilst roughing some billets out on the lathe at work, inception type shit. I wouldn't have all that material down the spindle, the chuck won't like it
I do this every day. Its not bad, the machine does most of the work. Custom fab/repair shop, 90% of the time i make single parts, 8% its a 2 part job. Ive done mass production, I hated it.
Thanks. Custom machining is always expensive. Sometimes we don't have the tools and the customer buys it for use unknowingly, its added to your cost and we keep the tool. Sometimes its best to find something off the shelf that you can modify. Like you buy longer bolts and cut them down, or design your thing around commonly available parts. I know those aren't always possible, I don't know exactly what you need.
Unless this is your project and you make the profit id just shop around. Buying a machine, tooling and learning it will be a long expensive journey process
152
u/Kiiaru 1d ago
If castle nut, why no hole in bolt for cotter pin?