Thread: CNC machines and why i dont care for them

Cant sleep so i figured id throw up a long-winded controversial post. ill do this here so the argument goes in my favor. first of all im young...25, so you know im not some jaded old timer who hates new fangled fanuc controls. Second of all i went to school for CNC, have taken Haas factory training, and did maintenance on them for five years, so im familiar with them and all the wonderful things they can do.

I'll Give you my back story to better help you understand where im coming from. I started turning handles about a week after I turned 18. I was a maintenance tech for OTC in Owatonna MN. Like many large machine shops they have both old and new equipment. As im sure most of you know repacement parts for older machines can be very expensive or have huge lead times (often both). Through trial and error (mostly the latter) and the guidance of some very patient teachers I started learning to make replacement parts. Since part of my job was fixing CNC machines and they offered to pay, i when to votech. There I very much enjoyed the first year of manual machining, but not so much the second year of CNC.

Like i said i did the maintenance thing for about five years. Always taking every chance i could to jump on the bridgeport or lathe. After that i was a HD mechaninc for a bit where they had an old rusty lathe in the back that no one else knew how to use. Then the fun started. i got a job in the twin cities as a prototype machinist for a company that makes laser sights for handguns (i got the job because i had made one of my own a couple years before and brought it to the interview ). They had a decent little setup, bridgeport, HLV, bandsaw, surface grinder, and a couple little CNC mills. The company was small, had some growing pains, and no bennies so i moved on. Now I run the proto shop for a large company.

Finally. To the point. As far as im concerned with a CNC theres no craftsmanship. No real skill. Its all software and button pushing. Almost anyone can learn CNC operation and programing pretty well in a year of votech. With manual it takes DECADES to master. I've been at it for almost eight years and i've barely scratched the surface. On top of that if your doing one-offs many parts can be done quicker manually than even using conversationial programing. i guess what brought this all on besides not being asleep is even though its still a viable skill most trade schools dont offer courses anymore. its mostly just a few classes and then on to the keyboard. I know ONE other guy my age that knows how to turn handles....

maybe this will explain why a cnc machine wins over a manual.

You can operate a cnc machine manually, but you can't machine in 3d with a manual machine.

Originally Posted by pende

Almost anyone can learn CNC operation and programing pretty well in a year of votech.

As someone proficient in both manual and cnc, this is bullshit. You can learn that in a week if you've half a brain, but it's useless knowledge on it's own.

More to the point, of all the people I've seen claim that CNC machining requires no skill or craftmanship, I am confident that none of them could make the stuff myself and others with the same skillset make on a day to day basis if they had the rest of their lives to learn how to do it.

If this post comes off sounding arrogant, that's because it is, but no more so than yours.

Of course many of us 'like' manual machining. The guy who pays you can pay you because of CNC. If you had to do what that CNC does all day, you would hate machining. Like drilling, countersinking and tapping a thousand holes. Sound fun?

Sorry to say but it doesn't sound to me like you've made much of anything demanding yet, and that time is more than plenty to become excellent and efficient at manual work.

As to 3axis, I do stuff manually that would take a 3axis cnc and it wouldn't even get close to the same finishes, manual has its limits but also its places.

Craftsman this and that doesn't matter one bit, even less anyones view of what one is. Reality is you either make good parts on time and efficiently using the equipment at your disposition whatever it be and turn it into $, or you don't. Making $ at the end of it is the only skill that matters.




not sure why this is in the bridgeport section...

it occurred to me while reading this, that either A; you have never really spent a lot of time at the handles at all, or B you started this thread just to wath the fire works...

ive only met a handful of people who say they prefer a manual over a CNC, and all of them are people who don't have the slightest clue how they work, much less how to run one PROPERlY. Oh, and this may be a bit of a surprise to you but... CNC tech is here to stay... without them you wouldn't have any need for the "proto shops" you spoke of ..

He summed it up quite early! He's only 25. Not enough experience or skill in precision machining of complex parts to even fathom the idea of the benefit of CNC. Gime him a job of simple job of say drilling and tapping 5 holes on a 200 square plates, be done before you leave for the day! He'll learn to appreciate CNC the hard way.

Originally Posted by pende

Cant sleep so i figured id throw up a long-winded controversial post.

Finally. To the point. As far as im concerned with a CNC theres no craftsmanship. No real skill..

Or flip the argument. (For example) As far as I'm concerned, there's no real skill or craftsmanship in manual machining, all you do is turn handles.

As someone who does a lot of manual machining in my shop, I can appreciate your point of view. There's a challenge every day in the protoshop, with don't-screw-this-up-because-you're-only-making-one-and-the-blank-is-expensive being an everyday blood-quickening occurrence. Beats the hell out of churning out the same CNC part every day for a week with no programming changes allowed.

And as someone who programs, sets up and runs CNCs in my one man job shop, I'm never bored. I do small runs (almost always fewer than 100 parts) and if I'm not otherwise occupied, think about how I can make the part faster or better.

CNC just increases my options. It allows me to do things I can't manually (as RDR pointed out), produces parts more consistently than I can and can do the boring stuff faster and better while I'm doing something else. It's a moneymaker. Probably not something you think about as much as I do.

Sounds like CNC bores you. Try writing, debugging and running a program to 3D remachine a plastic injection mold that's got about $25K in it already. Oh, and it's needed next shift. That'll lift the boredom of anyone but a dead person.

Don't cut off your options. You're young and enthusiastic and hopefully, have a long fulfilling life in machine work ahead of you. CNC can be fun, too.

Neil

Originally Posted by thesePAPERwalls

it occurred to me while reading this, that either A; you have never really spent a lot of time at the handles at all, or B you started this thread just to wath the fire works...

ive only met a handful of people who say they prefer a manual over a CNC, and all of them are people who don't have the slightest clue how they work, much less how to run one PROPERlY. Oh, and this may be a bit of a surprise to you but... CNC tech is here to stay... without them you wouldn't have any need for the "proto shops" you spoke of ..

Well, I for one do prefer manual over CNC. BUT! that's because I'm 400 years old. I've made some pretty neat shit over the years and maybe even wowed a few people. Well, dumb ones anyway. If I had to do it over, I'd sure as hell have at least one CNC. I have refused many jobs to where a CNC would have made a good buck for me while (at the same time) I was running a manual. This stage of the game....nope!

I think it's just a question of the right tool for the job. I love manual turning, and generally prefer to use a manual lathe for anything I can, but once you've had a taste of having to push out 20 complex pieces asap on a manual machine, you appreciate CNC. Automation can be wonderful, and can be after all what lets you focus on exercising a creative skill. Of course it's not just about automation either: there are things you just couldn't do on a conventional milling machine.

rpc

Perhaps i did not make my point clear. Yes is did start this to start a fire. I put it here because bidgeports and hardinges are the predominate manual machines. I dont like the fact that the number of capibale manual machinist is dwindling fast. I get the feeling that a lot of you read the first two paragraphs and started writing a reply. i have a VERY good understanding of CNC and all its wonderful capabilities. I dont like the fact that a lot of "button pushers" who never went to trade school call themselves machinists when they are machine operators. as far as questioning my expeirence or ability with manual machining, i already clairified that i was no expert, but i do have more than 10000 hours spent in front of a Bridgeport or lathe. heres some of my work. nothing too special, but all made from prints holding +/- .002 on most features. I probably shouldnt have started this post, just thought it may be an interesting conversation

Originally Posted by gregormarwick

As someone proficient in both manual and cnc, this is bullshit. You can learn that in a week if you've half a brain, but it's useless knowledge on it's own.

More to the point, of all the people I've seen claim that CNC machining requires no skill or craftmanship, I am confident that none of them could make the stuff myself and others with the same skillset make on a day to day basis if they had the rest of their lives to learn how to do it.

If this post comes off sounding arrogant, that's because it is, but no more so than yours.

+20

To the ACTUAL point - it was obvious that he is 25 before actually stating so.

Ah, to be 25 again.

Originally Posted by pende

i already clairified that i was no expert, but i do have more than 10000 hours spent in front of a Bridgeport or lathe. heres some of my work. nothing too special, but all made from prints holding +/- .002 on most features. I probably shouldnt have started this post, just thought it may be an interesting conversation

10,000 hours eh, well we all bow to your experience. 3.5 years stood in front of a bridgeport or lathe, i and most on here did more than that in their apprenteship and still knew nothing at the end of it. Wait untill you have 35+ years of experience before you come out with these sort of comments, then you might get listened to.

My perspective as someone who spends about half my work time in SolidWorks and a lab designing stuff made by machines, and the rest in my manual machine shop making parts:

I love my manual machines, but sometimes it's a necessity to design something would be a fixturing and tool changing nightmare on a manual mill. Designed for CNC it gets clamped, all the various operations just happen - the CNC being so dumb it never loses datum zero-zero -
flip the part and finish the bottom.

The prototype or proof of concept version on the other hand may be greatly simplified so that it's even possible to make it w/ a manual will w/ DRO.

And if there needs to be 2 parts, or 20 or 200? duh. If a NEED for consistency and repeatability exists, why pay a talented human who can make complex decisions when there are robots who will do exactly what I want without human intervention.

The division of good machinist/good CNC machinist seems a silly distinction. If you're a good manual machinist, you could be a better one if you were also able to adopt current technology as well.

If I had any production work at all I'd absolutely be looking to add CNC capability to my shop. But buying a CNC machine doesn't make one a machinist any more than buying a Bridgeport.

Love it or hate it. This ones simple for me....If you don't stay with the times, you'll be saying goodbye like Whitney Houston.

Of course manual will always have its place, but that market is shrinking. Some of these coversational "Tool room" cncs can be programmed at the control, and making parts in minutes.

Well I for one don't think age or yrs of "experience" has much to do with it. I went full time in my shop at 23, just like many here have, 28now.
Sure 30yrs of jumping into different fields of machining and manufacturing every year would be pretty awesome, but who really does that and gets that diverse of a skill background. I picked a sector of machining I enjoy and I try to be as good as I can at it, there's a few of them I'd never want to work in.
Seen plenty of guys with 30yrs experience that would go broke in a minute if it was on their dime, and also seen quite a few guys who never worked a day in the trade and just do it as a hobby that do amazing stuff that would put plenty of journeyman to shame.

Too bad the boss won't pay me to play on a manual mill. Something about making money. I just tune him out...

Honestly, I'd rather drive a mini van than stand at a manual machine all day.

A Haas tool room mill starts at $27,000. A good knee mill will cost you $18,000. Seems like a no-brainer.



Would you care to share how long it took you to make that first part you show? With a CAM system and a CNC mill, I could program and run that part in less than 2 hours. That includes all set up. If you think CNC is just for production, you're dreaming.

Any tool is only as good as its user.
Plenty of hacks out there with bridgeports- you dont have to spend a hundred grand on a VMC to be a hack.

On the other hand, I have seen some true artists who, given access to a CNC Mill and CAD, produce things that you could never imagine existing.

If all you care about is running parts, as fast as possible, for the cheapest possible price, then, of course, CNC is the clear winner.

However, for people who are designing things, then making them, the idea of ruling out some tool or technique for ideological reasons is just silly. Why would you want to limit yourself?

Of course its a good idea to learn manual machining first. My machine shop teacher made us learn to sharpen drill bits, properly, before we could touch a single machine besides the grinder. That weeded out half the class in the first week or so. I am far from a master machinist, but having spent time on manual lathes and mills teaches you a lot about feeds and speeds and different setups and cutters and alloys and, well, bad noises, which you cant learn from a book, and cant see when you are standing on the outside of the shower stall, and all the hot steamy action is taking place inside. There is no substitute for hand/eye feedback, for actually feeling an end mill snap, or smelling what too little coolant smells like.

Nonetheless, every tool can be used for good or evil. And great good can be done with CNC machines that is often only possible manually if you are a genius with ultimate patience, and six months to spare.

My late, sorely missed friend Grant Sarver revolutionized blacksmith power hammer tooling, and blacksmith tong design and production, with a laptop and a Haas VF2. Much of what he did, 3D shaped tooling, would only have been possible at enormous expense and time with a 3D Deckel pantograph machine in the past. ONE tool might have taken a month to build. He whipped out several variations in a day, allowing him to field test them, discard losers, and go into production with winners. He was a great example of someone who changed a small part of the world, thanks to CNC.

There are lots of other examples of people stretching the limits due to CNC. Even when its theoretically possible to make the same thing manually, if it takes two weeks, its mostly dick wagging to do it on a manual.

I'm like Ray and have been at this for lots more years that you've been alive. Both machines have their place. I see that you've made a few trinkets also.

Now, come back and tell me how terrible CNCs are after;
you've spent 2 weeks cranking on a Volstro head with tapered endmills for an aluminum mold cavity
you've spent a couple of days drilling spring pockets for a draw die
you've spent weeks machining a die opening because of weird shapes and angles
you've spent 2 or 3 days drilling and reaming holes in the back side of a plate so you can cut a bunch of curves on a rotab
you've spent a week machining 100 shafts on an engine lathe for a couple of prototypes.

There are many more jobs that I've done over the years that I would have loved to use a CNC on. We do stuff all the time that you'd have a very hard time doing on a manual. We have jobs that require a very good operator and a programmer that knows what they're doing.
JR

If you had to quote the parts, buy the steel, and produce a quality part, mold or die on time and pay the light bill,you would change your tune in a hurry.