Metal Lathe Made from Scrap Auto Parts
flyingkmachines.wordpress.com
flyingkmachines.wordpress.com
7 volumes total. Typeset on a manual typewriter.
My favorite Dave Gingery quote: "I spent half my life trying to figure out how to do a fifty dollar job for fifty cents. I spent the other half looking for the fifty cents."
One afternoon i had my mold ready. Fired up the forge, and melted down some aluminum. Then i realized how wildly unprepared i was for dealing with molten metal. i managed to pour a little bit, but that was a fairly dumb risk.
came up with a new plan for a side loading forge, smaller crucible and better tongs. Then i went and bought a little sherline mill.
The book on casting is amazing, and i have no doubt most people can build real tools. but it's going to take a long time, and it's going to take several tries to get anything worth anything.
I don't regret any of the time i spent on it. And perhaps i should have given it a few more weekends. i feel like i got far enough along to get a sense of the scale of what Gingery did. It's amazing. I think he undersells how much skill he built up over 50(?) years. And i think anyone attempting this will realize how painfully unskilled they are. But there's enough there. you can get there if you're willing to put in the time.
https://mitpress.mit.edu/books/foundations-mechanical-accura...
It's very interesting, looks like a lot of fun to build, but the end result is barely usable.
If you have any value to your time, buy the basic machines, fleabay for the tooling, and get on with turning metal into scrap ^H^H^H^H^H^H parts.
Who has a home shop?
So anyway.... I needed to learn mold making. Which meant I needed to learn some CNC. So I did a few simple things on the Tormach 1100 that the TechShop had. Great fun, but it really takes a lifetime to learn all the tricks, if then. I have a friend who's dad owned a machine shop. The guy who finished the 2-year tech school degree and has been a full-time machinist for 10 years is "the new guy". There are so many tricks to planning and fixturing, it is endless. As a hobbyist, I think you just have to decide what it is you want to do, and learn enough to do that, and to do it safely. I have no delusions of ever crawling out of a pit of relative cluelessness.
So I have one of those cheapie manual mini-mills. It is OK for some simple things, I could never make a mold on it. Someday I want to have my own Tormach -- but I already can't park any cars in my garage :/
In a previous life, I assembled extremely specialized custom CNC's for precise machining of small, delicate parts. We used off the shelf CNC controllers available at the time, which drove large stepping motors.
It's a blast. Be safe.
I noticed the key left in the chuck, on that blog. Oh, my eyes! Granted, it was probably just for taking the picture, but it still gave me the heebie jeebies. ;-)
Haven't done anything in the last year or two, though. Turns out, long commute and job at a start-up sucks your soul really hard :(
Though, equipping my machines with power feed taught me Rust and got me in that startup on the first place :D
https://www.youtube.com/watch?v=SOw9WqMOHjA - making files for his recreation of the Antikythera device.
My understanding is that this isn't entirely right. The block deforms under the combination of temperature and head bolt tension when fully assembled and in operation, and this is taken into consideration when machining the block.
When cylinders are re-bored there's supposed to at least be a mock head attached and fully torqued to spec to ensure correct results when assembled.
that's not usually true, and it'd be pretty difficult to achieve without a different jig for every engine.
When I spent time in the engine shop, we used a mag-table/mag-chuck for steel parts, and we used table vices/clamps for the rest of it. We would start with inspection and disassembly, move on to parts-holding, and then finally we'd bore/hone/surface, in that order.
There is a 'mock head' installed in that the piece is being held to the work surface, but other than that it's not typical to add more structure when machining -- it makes things much more difficult to move around.
For (very) high performance engines, some manufacturing processes require the engine to wear an external girdle before finish; but it's not too common elsewhere or in the aftermarket world.
For flow-benching head I've have seen the head bolted down like you're talking about, but for that they're trying to approximate an engine's flow.
While use of the torque plate in re-boring is apparently more optional than I thought, the point stands; these things aren't ncessarily square when unassembled and the original manufacturer of warrantied engines is going to take distortion into consideration when machining the new parts.
On an unrelated note; EVs can't take over fast enough, good riddance of all this archaic ICE junk.
1. The manual machines are really only used by hobbyists anymore. This is less true for Bridgeport mills (almost every shop has one) and manual lathes. For one off jobs which are always needed in a shop, it's much quicker to perform on a manual machine vs a CNC. Manual lathes tend to have a larger work envelope than common CNC lathes.
2. Price doesn't scale with machine size, often the opposite. Bridgeports are universal and in every shop, larger mills less so. A Bridgeport weighs 2000 lbs and sell for $1500-$5000, when you get into 6000+ lb manual machines, they sometimes sell for $500-$3000. The reason is that they are no longer used in production and they are too big for most hobbyists. Moving larger machines is much more difficult. North of 6000 lbs, it is very difficult to haul the machine without a CDL (CDLs are generally required when the trailer is 10K+). Riggers (the craftsmen who load the machine onto a trailer) and transport can cost more than the machine itself.
3. Tooling (drill bits, lathe tools, mills, fixtures) is frequently much more expensive than the machine itself. Finding a machine with tooling is a really good call.
4. There are great deals on machines in the midwest. I scan the detroit and chicago craigslist in particular.
5. Kearney and Trecker milling machines are super cool. They are noted for being the pinnancle of machine tool engineering - all done mechanically [1].
6. For lathes the top brands are probably Monarch and Axleson, followed by mid tiers like Clausing, Leblonde.
7. For all machines, the machinist is more important than the brand of the tool.
8. Avoid older CNC machines, parts are hard to get and expensive. I would be afraid of any CNC machine made before probably 1995.
9. Rigging equipment is pretty cool and necessary for running any type of shop. People do all kinds of cool machine moves with combinations of pallet jacks (~$100 - lifts 5000 lbs), hoists, anchors, Egyptian rolling bars, digging bars, machine skates, and engine hoists. [2] [3] Hire a rigger though.
[1] https://www.youtube.com/watch?v=kANvdzoVUfw
Mostly it is just lift-pivot-lower repeated many times to walk a machine along. For longer distances I’ll get it aimed right and up on rollers. For raising or lowering you need an assistant to put the cribbing in or out, but raising a ton of lathe 2 feet to work on the motor underneath is pretty easy, just always have secure cribbing in place so it can’t fall.
https://www.youtube.com/watch?v=MtxA20Q-Uss
The rest of this video series is also well worth watching.