Sam, I take over as the crew chief for the manual machine shop for the tooling department at work next week. So it isn't completely gone, but definitely diminished.
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This one is kind of near and dear to me Very neat way to fix a rim.
Although not in this video, I like how these guys use calipers. You don't see that too much anymore. They take a very fine "feel" for getting the right measurement. I use them on occasion, when I don't have a set of dial calipers, or vernier calipers, that'll fit the part. Inside, or outside, calipers can really extend your measuring capabilities.
Very handy to get the diameter without removing the bolts, or if you don't have access, or whatever............ I've got a nice selection of Browne & Sharpe, and Starrett, that I've picked up off of Fleabay over the years. They're amazingly cheap for the quality. Only buy ones that the seller has provided closeup pics from all angles. Pay particular attention to the contact areas..........no nicks, or other damage.
Where I have full access (bolts removed), I can use a vernier. These used to be really cheap,, dunno if they are anymore. They're surprisingly accurate. All the Chinese, and Indian, made tools have skyrocketed in cost.
I really don't think, unless I'm mistaken (which I usually am), that manual machining has gone completely by the wayside in this country. I imagine it's just not practical when it comes to competing with outfits that are set up for CNC. Although............I'd imagine it's still competitive for one-off parts.
Sam, I take over as the crew chief for the manual machine shop for the tooling department at work next week. So it isn't completely gone, but definitely diminished.
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I haven't built anything I can't throw away. Perfection is the journey.
Mac
The old ways take skill, not that the CNC machines don't I guess, it's just a different type. Watch a couple of this guys videos, he knows what's what and how to use gear and do repairs on equipment, I think Samm and him would get along; https://www.youtube.com/c/CuttingEdg...stralia/videos ................Mike
You need a bigger lathe Sammm.
IMO,, CNC blows away manual,, even for one part,, because measuring with digital is SO FAR BEYOND the accuracy of turning knobs by hand.
I had manual, and CNC in my shop,, the only time manual was used was when we did not have the capability in a CNC machine.
Those Pakistani videos, like the crankshaft video shows the lack of accuracy because of the lack of digital measuring.
IMO, the crankshaft survives because it is only going to operate below 1,800 RPM,, anything greater, and the bearings of the engine would beat themselves to death,, quickly.
The same with making hydraulic cylinders (they call them rams),, ZERO accuracy,, the manual made parts are not interchangeable,,
that can be seen in that they "number" each assembly, to that the set of parts can be used together.
They were using a large blue magic marker to position holes for assembly of the hydraulic cylinders,,
then they drilled the holes with a drill press that had close to 1/4" of wobble in the drill bit before the bit contacted the part.
I think virtually all the drill presses that they use have that 1/4" of free running wobble,,
I admit that some of what you say is merited. But..........................
I do stuff all the time that isn't interchangeable. The very nature of taking old worn parts, and rebuilding them, can make them non interchangeable. You're generally removing metal, and turning/milling to new dimensions. The part will work, but it sure won't fit another like machine in a lot of cases. But, that's not really the point. The point is to extend the life of an aging machine that has more intrinsic value, than market value. Or, the replacement value exceeds the money you have in your wallet. And oft times............replacement parts are either unavailable, or priced too high compared to the value of the machine.
The couple of wheels I've rebuilt will not fit another like machine. My goal is to reinforce them way beyond what's available. This thickens the center dish way beyond anything that will fit a regular hub..........or at least a hub with standard bolts/studs. It's strictly one-off. But, they function better than OEM for my application.
Accuracy...................... Hell, I dunno. A machine tool is as accurate as its ways,, and bearings. And as accurate as the tolerances called for in the finished part. If you look at current ISO standards, they're pretty sloppy. This is primarily due to globalization. Gone are the tight tolerances that existed when the developed world manufactured parts. Now, it's a hodgepodge of stuff from all over the world. Case on point.............Boeing is struggling with issues brought about by outsourcing. The stuff arrives,, and doesn't fit. If you look at the history of machining standards..........WWII was a bellwether event. At that time, fastener standards had to be revised to accommodate parts coming in from other parts of the world. It was the first real need for international standards. IIRC, the history of thread standards is pretty cool.........been a long time since I read about it.
As far as engine rpm goes (crankshafts)........................ While a diesel engine, particularly a high compression, heavy duty, truck engine, may run at lower rpm, it generates a huge amount of force on the journals. So, in some respects, the tolerances are probably tighter. Now.........in favor of your view.......we just see the repairs on the videos, we don't see the results for the end users. But, I suspect that they must be fairly acceptable, or the shops would be out of business. Maybe not another 6000hr engine, but enough of an extended lifetime to make the cost of the repair economically feasable...........I dunno.
I'm quite sure that the machine shops in the videos are going enterprises, and the people who own them, and the people that work in them (the skilled workers at least), are probably middle class folks in that economy. They look well groomed, sport nice jewelry, and electronics. The cars in the driveway don't look to be junk. It's all relative. You can't expect "Third World" people to be any less stratified than society here in the U.S. All things being equal, they probably live a comparable lifestyle in terms of possessions, and security. That's my take anyways, I might be wrong.
Don't be fooled by work clothes. A loose fitting smock,, and sandals, is probably almost a requirement in those climates. These guys aren't starving peasants. Now, the guys in the factories in these videos are probably lower economic class people..........................like anywhere else. I don't imagine they live too well. But you can be sure that the owners do. Pretty much like it is here.
You might also study pictures from the early 20th Century. Workers in the U.S., and Europe, wore their everyday clothes to work. They couldn't afford work clothes. For S&G's look up the history of shirt collars...........they were interchangeable because people couldn't afford work shirts, so they changed collars when they got dirty. People really lived on the edge in those days. Times were hard for the working class...............Hell, they still are.
Whether it was Hells Kitchen, the Bogside, or the West End....................nobody lived very well. It's the reason the unions were established. To this day, we benefit from those unions, even though most of us don't belong to them. They were responsible for better working conditions.
Last edited by farmersammm; 01-03-2022 at 03:54 PM.
I thought of one more thing . The knob is dependent on the leadscrew. I'd imagine a crankshaft grinder, or a surface grinder, probably has a leadscrew that's finer pitched.............making each movement of the knob all the more accurate. Everything that exists today, is based on the old tech. Mechanical movement is still mechanical movement. I think even a step motor still relies on some sort of gearing/rpm for locating it along the path of the cutting/machining edge.
CNC improves precision and speed. I suspect a manual machine with quality tool and gauges can be comparably accurate.
Had a regular client bring in a shaft off of an exercise machine. I told him it would be easier to rebuild the part. He left it with me to build up and turn down the races, then he needed it sooner than i could get to it. He took it to a machine shop. They said no problem, then machined it. Returned it to him. ....Oh they were 25mm metric threads, not 1 inch. So, the CNC part worked, the technician ASSumption missed.
I think the machine shop was actually cheaper, though. He just had to get a 25mm. nut
The one thing that makes me drool, is roller burnishing
I love the music as much as I love the concept, and the tool. This is the one area that manual won't work I'd suspect. It's pretty precise stuff..........not only the movements, but the applied pressure.
I remember a few years back, when I bought my lathe.
I had this funny sinking feeling, sort of a knot in my stomach. It was a lot of money. Around maybe $3500. Stupid really, considering the money in the market, and the money out there running on the hoof............but it's a pretty sizeable outlay all in one bunch. It felt like what it felt like this year, when the docs got ahold of me. Scared, ya know...........
I thought it might be a white elephant.
Then I really got into it, I mean full bore It's a great substitute for failing eyes. Doesn't require sharp vision..................Hell, it's a machine.
The tool grinding was the biggy at first.
Then after a while, it didn't matter. Who the Hell's gonna look at it. Most of the stuff you do is fine within about 2-5 thou. Hell, it ain't the space shuttle.
After that, it was fixtures, and turning aids. More versatility. Man..........it's been a good thing!!
Use it all the time now.................nothing fancy, carbide is fine, don't need a mirror finish. Life changes for the better most times.
I only work with 4 kinds of metal (excluding aluminum, which I don't like). 1018, 12L14, Stress Proof, Fatigue Proof, and semi steel........Hell, that's 5 kinds. But anyways.............it's pretty simple.
Many things were built from parts that were made on machines that didn’t even have a dro let alone cnc. Any machine is only as good as it’s operator. There is a whole pile of cnc crash videos. To me cnc shines where you can make a part store the file and down the road make more parts by pulling up the file.
Millermatic 252
millermatic 175
miller 300 Thunderbolt
lincoln ranger 250
smith torches
lots of bfh's
If it dont fit get a bigger hammer
Sometimes, actually most of the time be it a lathe or mill, the machine isn't the expensive part. Add up tool holders, insert holders, chucks, centers and who knows what else and it adds up quick. Fortunately a lot of the import tooling is fairly decent and affordable. Best thing I added to my mill- drill unit is an import DRO. Let's not forget rotary tables, indexers, nearly every drill size imaginable, reamers and on and on. By rights if the machines were free and you bought everything needed to go with , it would still be very expensive.