Whatever makes money.
There's definitely been quite a few jobs that I did on my CNC mill so far that would have taken me quite a lot more time and just been a PITA to do manual. 30minutes at the computer and next thing you know it looks like I almost know what I'm doing. With that said... it hasn't paid for itself yet nearly as much as the manual machines do.
Without CAD/CAM I'd be majorly screwed though, no way I could type up those codes by hand faster that I can do manual if it was for low quantity parts. I think that's the big improvement, its often as fast/faster/easier to CNC 1 part now. But I still love being hands on and often have to force myself to use the cnc for some parts.
I know trig but probably haven't "trigged something out" in 15 years. There's no need when I've got cad/cam. Doing the math long hand only increases the chances I'll make an error.
Conradulations on your program being top rated. I wish there were more like it.
Like you said, knowing how to do some over those older manual techniques allows you to better understand how to go about making something. That to me is really what being a machinist is about. Any old dummy can learn to operate a machine, but knowing how to make stuff is what makes a machinist. I pick the machines, cutters and order of operations. The actual operation of machines and programming of cnc's is the easy relatively easy in my opinion. The hard thing is in figuring out how you're going to make a part in the first place. Or harder yet, how are you going to make it fast and cheap?
Guys, this is really simple and not worth this kind of debate. We work with tools. Plain and simple. You use a wrench to turn a bolt and a screwdriver to turn a screw, CNC to manual is the same thing. CNC and manual each have thier own applications, strengths, and weaknesses. To lament and devalue CNC's because it doesn't take the same skillset as manual machining is silly.
If manuals suit your needs, buy manual machines. If not, CNC.
Quote by SND: "But I still love being hands on and often have to force myself to use the cnc for some parts."
This was my intent previously. I do realize that there are jobs which come off of CNC's as nothing more than a normal day's work which would be an incredible pain to do on manuals. Some of the 3d work would be nearly impossible. Although I love working with manual machines and having the challenge of doing some of the more interesting work that comes through the shop on them, I'm not going to kid myself in regards to their capabilities or to the time frames in which they can complete some of these jobs. They are money-makers now, and will get better at that every day. Most of the die sections I program & cut on wire EDM now in one setup would have required form-ground, multi-piece sections (plus many, many hours) just a few decades ago to achieve the same geometry.
As far as kpotter's original question regarding whether older technology can or will replace newer technology, I'd think not. In the machining and manufacturing world, there isn't room for sitting idle. You just get left behind. I'm not saying that manual machining is dead...it isn't. Nor will it be for any time in the near future. It's role has just been changed from where it was 40 years ago. SilveradoHauler wrote an great post regarding that. Manual machining nowadays isn't geared for manufacturing (at least in any decent volume), it's geared for specialty and niche work...and it certainly doesn't hurt if you enjoy cranking handles.
Let's step back a couple hundred years. Before the start of the 20th century (1900), everyone knew how to handle horses, mostly ride, walk behind and all the other uses of "real horsepower". Today that is almost non-existent. Is it a skill that future farmers and tradesmen still need? In general, no. For a declining few, the horses were used up to and perhaps through the 2nd world war. Machines have replaced the horses.
To Potters' question, do we still need to know the old skills now? I would say yes, but the need will be declining like the horse over the next period of time, 50 years, 100 years? Some skills, like lacing a leather belt, are simply not used (South Bends excepted). Fabricating your own tools with a forge. And so forth.
Manual machines will still be part of a lot of small shops for a long time, because 60 year old iron will still make the same quality parts today as then, of course with maintenance. At the current state of CNC, a 20 year old machine may be in perfect mechanical condition, but the electricals are obsolete and unreliable. This I think is going to be the real issue. Unless those used machines are priced insanely cheaply, such that when they fail they are just scrapped, I believe startups will be with new CNC or old manuals.
Oh, and for those few that think CNC is the latest in automated machine production, don't forget that all we have done is replace cams and gears with computers and servos.
nothing Wrong with cranking handwheels for onesy twosey parts , but when it comes to making many of the same or complex parts , you can't beat the cnc machine . I had to make a choice between a manual mill or a cnc , production made that 1 . I still do simple manual ops via the hand wheel or jog mode for the onesy twosy parts . I've made soom cool stuff I thought I never be able to make on a manual . Dare I say , even the hobbiest are cnc'ing thier "bleep" machines . I'm still using a manual lathe till I build cash for the cnc 1 . As far as HS shop , I attended the last year for it at the HS I went to . IMO , you should learn the basics before learning CNC , I has been a big help for me
I teach high school machine shop and welding classes. We have a small cnc mill and a cnc plasma table, the rest is all manual machines - 10 lathes, 2 bridgeports, 1 horz milling plus 12 welders. My classes have 12- 15 students per class. the main reason for the manual is not what they can make on them but what they can learn. They learn blue print reading, shop math, precision measurement, how to do a job to the best of their ability, tooling, an a whole lot of other things. Plus we have fun and it is interesting. That's why I think everyone needs to learn a little bit of manual machining.
Any time somebody has a need for any given skill, and there is either a market for it, or sufficient interest, SOMEBODY will figure out how to do it.
I think the whole "Lost Art" thing is a bunch of bunk.
I know guys who knap stone knives, hot press rivets for Titanic television shows, pour iron from bloomery style setups, plow with draft horses, hand make tack for draft horses, put ships in bottles, hand forge anchors for boats, make nails by hand with a hammer, knit socks, hand skive leather skins, build 1920's race car blocks from scratch, make ink from burning bones, and a hundred different "lost" arts.
Where theres a will, theres a way, and if anybody NEEDS to know manual machining, its far from gone from the surface of the planet- in fact, as old skills go, its one of the most common, there are manual machinists on every continent (yes, Antarctica) and in every country, and will be for the foreseeable future.
And kids still know how to type, too.
If the doom sayers are even partially right and the big phfttt happens later this year, even a partial one ,say a super solar flare that knocks out large portions of the grid. How long before you could rig those old manual machines with a set of pullies and a make shift line shaft and get back to making parts? Might need to hook up with some of the live steam crowd, but I bet it would be before the large CNC shops got back up and running,as anything that acan take out the grid is liable to do a number on the innerds of the computers as well.
The old skills matter in slave countries, where shops can actually make money on it. Other than that and you get some prototype and one off type stuff, and of course repair work. I don't think they will completely go away, but the need will continue to decrease. While the demand for manual machining skills will decrease, so to will the number of machinists who are good at manual machining. It will be interesting to see what happens as a result over the years. Might be wise to keep passing down these skills in some form or another to those interested.
I ran CNC mills and EDM's, and did the CAD/CAM work at a few small mold shops from 1984-1998. When I burned out on that I started my own small 1-man shop using all manual machines. I repair and maintain molds, make jigs and fixtures, and do 1-offs and repair for several various industries. I've never been busier than I am this year. I live on the edge of a metro area that has a population of over 3 million, and at one time (20-30 years ago) had many, many machine shops. The number of shops has been vastly reduced in the past 10 years, and the number of shops that do the work that I do is even more reduced. Most shops now only run production for a small list of customers. Hardly anyone is left to do the work I do, but yet it is necessary to keep plants going. I now have customers driving 20,30 and even 40 miles through heavy traffic to bring me work. When I started on my own in 1998, most of my customers would've come from a 10-mile or so radius. I'm not saying that my work load is growing because of how great I am, but rather that it's growing due to attrition of machine shops that do one off work in my area.
Originally Posted by andywire
Consider the "English Wheel". When I first saw one, 40 years ago, the old man using it bought it from a scrap yard for the value of the metal.
Do a google search and you get 60 million hits, because of the hot rod shop reality shows. I think this cottage industry stuff appeals to people, because it's something that can be done with simple tools & a lot of sweat equity.
And I agree with Reis, as long as someone has an interest, they'll buy a book, or go on the internet, & figure out how to smelt iron from river sand, or whatever.
The lucky few will make a living at it.
'Pros and Cons to everything'
I have never run CNC - but love CNC for the selfish reason that I have filled my shop and garage with 70-100K$ worth of machinery (at prices 60 years ago) for a 95% discount - practically scrap value...thank you CNC..
And so then for me - the 'old skills' do indeed matter..thank you PM website
Oh I agree, the more you can eliminate human error the better. My biggest problem is getting the students able to 'estimate' an answer. Sometimes they rely too much on their calculators or CAD. Even with those a wrong button can be pushed. But when they take 12 divided by 3 and get 4582.7633 from the calculator and write down that answer; it drives me crazy!
Originally Posted by John Welden
You have a really tough job. It's so hard to teach people when they're miles off from where they're supposed to be. I believe a good atitude to have in a machine shop is to be skeptical of everything. I don't care what the calculator or CAD says if something doesn't look right. Maybe you learn that after trusting things will be right and then screwing up a bunch of times. I think it's good to act like an experienced aircraft pilot when machining and don't assume shit is right. Pilots that think they're too smart to double check are the ones that run out of fuel or land with the landing gear up.
Originally Posted by Mechengr07
You should post some pictures of your shop some time. I bet people around here would like to see what a leading shop looks like. I dream of tons of programs like yours for people to learn machining and other trades.
"Necessity is the Mother of Invention". Technological advances are usually made because there is an economic need for them. Production, and Not-So-Production tasks can be done faster, better and simpler by modern machines and software. These machines and the technology that drives them are a direct result of a skilled machinist recognizing room for improvement. Even those of us who made a career manipulating old machines to do a job can see that the new concepts are not only better, but entirely necessary to remain competitive. There will always be a place for the old in our system of production, as well as a place for those who capable of using old ways, but the days of a fully equipped machine and fab shop in every corner of civilization are over. Those of us who can still do it in our garages and hobby shops will pick up the scraps and be thrilled with the employment. Regardless, I may still upgrade some of my machines to something less than 70 years old someday, just to keep up. As an aside, I'm happy to see the anger management classes are working for John. Regards, Clark
I think I got a good little story about needing the basics.
I was running some parts in the cnc mill putting a thread on a shaft. I have run this program before with plenty of success I pretty much had it to a no brainer task (mistake 1) anyhow I have been loading and unloading these parts for a while and about the last 5 or so were wrong. Looks like somehow the x axis shifted about 0.005. so rather than scrap the parts I decided to fix them. took them over to the manual lathe and set it up in the 4 jaw (old skill 1) to chase the thread (old skill 2). Normally I like to just use carbide tooling its just easier. so I went to chase the thread with the carbide tool and since the load was changing turns out the tip broke (mistake 2). well I know that if I try that again the odds of it happening again are high and I only have 1 more. Just in case though I always keep some HSS blanks handy. so get out the fish tail gauge and get to work on the grinder (old skill 3) it ended up taking about an hour to fix mistake 1 but it would have taken 2.5 to scrap the parts and re make them.
So long story short without having the old skills to back up the new I would have been about 1.5 hrs behind. Knowing these kinds of things separates the button pushers from the real machinists in my opinion.
Thats pretty much how I learned when I was starting out. maybe not a bunch of times but I guarantee you that the second of whatever I made was leagues better than the first. Got it down to pretty much a 1 shot deal now but that has taken probably 10 yrs of f*** ups. (dont judge me too harshly I taught myself with mini tools)
Originally Posted by John Welden
Most all of the work I do is one-off parts or repair jobs. In my field of work all I use is manual machines, and Ive become very good at running them. I learned everything I know from growing up in the shop with my dad and grandad in our family owned machine shop. Seeing all the different type of repair jobs that came in and the different ways to use the machines and tools to get those jobs done was some of the best experience one can ask for. I have no experience with CNC machines, although i think it would be great to learn them too. Ive always seen the need for both types of machinists and shop. CNC's are great for high productivity and complex parts, but they wont handle all the walk-in repair jobs that my shop sees. I plan on sticking to what I know. I am a highly valued employee at my day job being the only machinist making lots of hydraulic parts, repairing shafts, and all the other stuff that comes in. I plan on dieing as one those "old school" machinist.
I agree abom, manual machines and old skills still have a place for one offs and repair work even simple parts. Its when your taking stock and making tens or hundreds of parts ,from scratch, that need to be the same is where cnc is invaluable but like my story earlier story even with cnc you should always have a solid foundation of old skills to back you up when you need them.