Manual Machining Or CNC?..

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What is better.Manual OR CNC?Take into concideration that most shops will not even talk to you if you don't want over 100 pcs. done with CNC...What is your choice?...zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:I think it depends on the job.Like you said, most shops won't even talk to you for less than 100 pcs with CNC.IMO, If you are doing a one-off repair job or part, then manual is probably the way to go. I use a manual bridgeport and lathe at work when I build our welding fixtures or repairing production tooling. No CNC, NC, or even DRO....old school all the way.Would I LIKE a CNC mill or lathe...hell yes!I just recently got a 4x8 CNC plasma table and it's the bee's knees.http://all-a-cart.comWelding Cart Kits and accessories
Reply:What he said.   It is the same way in cnc shops. The manuals make the fixtures for the cnc machines.
Reply:BOTH.  you gotta know when to write a program for a part that you could potentially make again, OR go ahead and tool up for a one off part. Its VERY part dependant.   Sometimes its way easier to write a program for a 5 axis machine than it is to attempt a ton of setups for a bridgeport.Vantage 500's LN-25's, VI-400's, cobramatics, Miller migs, synch 350 LX, Powcon inverters, XMT's, 250 Ton Acurrpress 12' brake, 1/4" 10' Atlantic shear,Koikie plasma table W/ esab plasmas. marvel & hyd-mech saws, pirrana & metal muncher punches.
Reply:I used to think NC for moderate numbers or very complex shapes and old school for the one off parts. In the past I've known folks good enough with conversational controls to program one off parts while the machine is making another part and do dozens of small jobs per day from prints.The later fellas earned some serious dough and that particular shop exported tooling worldwide.Matt
Reply:ZT,  What brand CNC table did you get?  I got mine from Torchmate and it is too the bees Knees.  I really like you sig line too.  Soory for the thread jack.BobI'm spending my Kids inheritance, I dont like him that much anyway!!!!!!Enuff tools to do the job, enough sense to use em.Anybody got a spare set of kidneys?  Trade?
Reply:Originally Posted by RbeckettZT,  What brand CNC table did you get?  I got mine from Torchmate and it is too the bees Knees.  I really like you sig line too.  Soory for the thread jack.Bob
Reply:Originally Posted by Matt_MaguireI used to think NC for moderate numbers or very complex shapes and old school for the one off parts. In the past I've known folks good enough with conversational controls to program one off parts while the machine is making another part and do dozens of small jobs per day from prints.Matt
Reply:kinda like, which is better- beer, or whiskey?Neither is better. They are different. However, since there have been essentially NO manual lathes built in america for over 20 years now, most industry has decided they can do the job with CNC.I know more and more guys who can, and do, one offs on their CNC machines quicker, better, and cheaper, than manual.A guy I know has a Haas TL1- the small Haas CNC lathe. It will do a lot of stuff a manual lathe wont- and he can program simple stuff FASTER than you can do it on a manual. He does one offs all the time, and makes more money on them than he would on the manual lathe that sits, unused, over on the other side of the shop.A lot of older guys insist on buying their first CNC lathe with manual controls as well- Haas, Romi, and others make lathes like this- and, within a month, realize, they just dont ever use the manual knobs- its quicker to do it CNC. Same thing with mills- learning to program a simple mill is so quick, that once you try, you dont go back.Certainly, there are big shops which have high minimums- but I dont know many machine shops these days that can afford NOT to have CNC. CNC is 50 years old, its hardly new anymore.I have a Bridgeport clone with DRO, and virtually every time I use it I wish it was CNC. There is virtually nothing that can still be done better with a manual. Certainly not on a lathe, and very little on a mill. CNC can easily run carbide tooling, meaning faster speeds, better finishes, and the ability to get much higher quality in exotic metals, hard stuff, and so on. There is no industry I can think of that still uses manual machines for production. For R&D, or repairs, or tooling, sure- but for production, why bother?A new CNC lathe is actually cheaper than a similar sized quality (not cheapo chinese) manual lathe.A new Bridgeport costs $15,000 or so, then add the cost of power feeds in all three axis, a DRO, a right angle head, and a rotary table, and you are paying MORE than a new Haas minimill, that doesnt need a rotary table, cause its built in, already has power feeds, and is CNC. What company would pay more for less?Now if you are buying used tools for dirt cheap, its a different story, of course- but for a profit making company that needs a tool that works accurately, CNC is a no brainer.
Reply:I'd go with a mixed machine personally.  CNC with manual controls via traditional wheels or pulse rotary inputs.  That way if you just need to do something once, or something simple, no need to design anything or write any G-code.  If you need to do a bunch of items or something complex, run it CNC.--Wintermute"No man's knowledge here can go beyond his experience." - John Lockewww.improvised-engineering.comManufacturer Agnostic:Blood----------Sweat---------Tears----|------------------|----------------|----Lincoln Red, Miller Blue, Esab Yellow
Reply:I will do 1 part with my PlasmaCam CNC machine with Hypertherm Powermax45. I just make sure my time at the computer, as well as setup time at the machine is covered. 1 piece is certainly more costly ( per piece) as compared to 100 pieces. On larger orders that are expected to be repeat orders I don't even charge for CAD (computer) time....I have a few customers in small job shops that rely on me to provide one-off parts with very quick turnaround. I make adequate money on every one of these orders to justify my time, often the parts are shipped parcel post, and I have the money for them in my paypal account before the customer even gets the package.Jim
Reply:This might not be true, as I havn't seen it personally. But I hear tell that those manual/cnc lathes (like the haas tl-1) can record your motions, while manually making a part turning the hand wheels, to create a cnc program. Now that would be handy for short run or design incomplete parts.Ian TannerKawasaki KX450 and many other fine tools
Reply:Originally Posted by zapsterWhat is better.Manual OR CNC?Take into concideration that most shops will not even talk to you if you don't want over 100 pcs. done with CNC...What is your choice?...zap!
Reply:Originally Posted by PassengerCNC, is better for everything, I don't have any manual machines, there is no reason to have one. I can make parts faster on the cnc's than manual machines, and they will be more accurate and have better finishes, not to mention tool life is significantly better.People who say otherwise just aren't competent on cnc machinery, simple as that.
Reply:Originally Posted by ZTFabWow...it's better for EVERYTHING?!...
Reply:Originally Posted by PassengerIf you don't know how to use cnc machinery manual machinery would be better, that is about it though. Not to mention painfully obvious.Why do you think otherwise?
Reply:Originally Posted by ZTFabThat is why I said it depends on the job.Both types of systems still have their place and uses.I'm just wondering how it is that you can make an all inclusive statement about what type of machinery is the best for EVERY single job under the sun. How is it possible that CNC machinery is the best for every single situation, job, repair, part, task and how could you possibly gather this wealth of information in order to ascertain that?
Reply:Passenger, ZTFab, others on the post,If you don't separate the software/firmware CAD part of the question from the hardware, cutting and setup, then we'll have an apples and oranges thread.Even the earliest NC machine was 'better' than manual because it would do the actual cutting/shaping/bending/shearing faster than the work could be done by hand.  I'm separating the set up time from cutting time, in that 'better'.What has changed in the critical path of time-&-effort between the two types of machines is:  software.  Newer software has made learning time much lower than ten years ago, while the manual machine requires a reasonably fixed number of hours of hand's on experience making your share of mistakes to 'master'.Just like in the early days of the PC any good manual typist on a mechanical Underwood manual could outrun the 'computer' so can a manual operator compete where the software time is too high.What has changed, 90% of the change in NC in the last 10 years, is the interface.   Now, for very few dollars, these current interface packages allow people who have spent time learning the software to draw in seconds or a single keystroke what took hours before.Same with the PC you're reading this site on, when DOS ran things you had to remember and type long complex strings of letters and numbers and punctuation to get anything done.  It took time.  Without the Graphic User interface  (software) there'd be no i'net or Weldingweb.com site to discuss.  This interface makes the tool (digital communications) available, but you can still use the telephone.I have an NC router and its usefulness is directly related to my familiarity with CAD to draw what it will cut.  Reducing (overall work) time is reducing CAD time first.I think the discussion needs to be converted from what's "better; manual or NC" to "How long does it take to (learn to) and draw; compared to gaining the experience to do set-up and cuts without programming"?That seems more the question since 'better' is time and effort reduced/conserved/minimized without giving up the quality results- right?Cheers,Kevin Morin
Reply:Sure software makes the machines easier to run, but things like mills and lathes, for basic stuff you might do manually are very easy to code by hand, and quickly. Especially on simple stuff.
Reply:It's not the tech, it's the folks using it. Case in point, in the 70's CanRon Tamper (Canadian) went NC as much as it could. Using G-Code the programmers and the operators who were machinists would slow things down when a forging was out of balance (some things need not be machined). They made good parts with some still working all these years later.Fast forward through a couple of buy-outs and conversational programming (I'm talking Mazaks and Okuma's here), where the size and surface finish are given and the machine works out the rest. The part I'm describing is about 65-70lbs and has a #6 morse driving taper on one end. Some last a long time some not long at all (if you guessed the short living ones have an out of round taper you'd be right).The jist is, you can't build a reasonably priced machine that can stand up to 6-800 RPM with an out of balance load (the taper is 2.1 to 2.25) and that's what the machine wants to run at, and have it equally stiff in all 6 axises of motion. PERIOD!People look at iron and steel and think strong, to me with enough energy it looks like a willow in the wind.Two owners later and several several other players trying to chase the aftermarket (in china no less), I'm not going to hold my breath for someone to wise up. I'm still checking the tapers for roundness when they need repair due to cracks in a locating keyseat and the samples still look the same.I still grind the taper and it locks.... If you don't understand the Pony you ought not ride it!Matt
Reply:OK..Good points here both ways..But you gotta ask yourself...Could you even bother to do the journal repair in a CNC machine over a good'ol Hendy manual lathe?I think NOT.It's all dependent on the task at hand..And I will bet 10 bucks to do that job the Hendy will win....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Originally Posted by zapsterOK..Good points here both ways..But you gotta ask yourself...Could you even bother to do the journal repair in a CNC machine over a good'ol Hendy manual lathe?I think NOT.It's all dependent on the task at hand..And I will bet 10 bucks to do that job the Hendy will win....zap!
Reply:Ok, I'll add my two cents The problem I have with my cnc equipment is often the machining envelope is too small for repair work. My mori only has 20 inches to the tailstock... simply not enough to repair a roll like zapster did. For production or most anything that can fit in the machining envelope cnc rocks. For a quick job machining soft jaws can be a bother and I often use the manual machine instead. Of course I cannot rapid like my cnc machines and as mentioned the finish and flood coolant are awesome.My cnc plasma cuts 0.25" plate at 130 ipm... I cannot move that fast and multiples are cake. That said I have a manual lathe and mill. Both have larger envelopes than my cnc machines. Both were dirt cheap to purchase. Rarely does a week go by that the manual machines sit idle. I have paid back the manual machines many times over, often on the first couple jobs.
Reply:Passenger, I think Zap was referring to another thread he posted concerning the repair of a direct printing engraving roll. In that case a repair done over 1 1/2 to 2 days saw machines running at best maybe 3 or 4 hours.If Zap had NC machines, the machining hours would have been cut down for sure, but the machines sitting idle while lift trucks are driven, materials found, preparations made while thinking things out would turn the NC equipment into a more high dollar per hour affair.Just for fun I dug up some old pics showing in place welding of a fan shaft which was also machined in place that night with a small master slide cobbled up to the fan (a real hillbilly affair that happens out there a lot). And the UA HVAC guys are going to ride me big time about the open disconnect and the alligator clip hookup of the welding machine (top side, unfused, don't look).This was a low speed makeup air unit that after several re-models of a hospital found itself "walled in". I got there saw the job, went to my shop for materials and scheduling the machining for that night and get more help. I got the shaft end prepared, gathered up tools, welder, gas and rods drove 60 miles back and welded till help arrived. When they got there I went home, by morning the fan was back in service when I visited the hospital.I didn't take the camera back as this type of work is not all that unusual for repair (but walling a fan in that tight was). I think the shaft was some 8' long in a 12' room and the housing couldn't be moved far enough to get it out...Matt Attached Images
Reply:That whole journal repair job was 7.2 hrs TOTAL.From the time it got put infront of me until I put it back on the pallett......zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.Originally Posted by forhireOk, I'll add my two cents The problem I have with my cnc equipment is often the machining envelope is too small for repair work. My mori only has 20 inches to the tailstock... simply not enough to repair a roll like zapster did. For production or most anything that can fit in the machining envelope cnc rocks. For a quick job machining soft jaws can be a bother and I often use the manual machine instead. Of course I cannot rapid like my cnc machines and as mentioned the finish and flood coolant are awesome.My cnc plasma cuts 0.25" plate at 130 ipm... I cannot move that fast and multiples are cake. That said I have a manual lathe and mill. Both have larger envelopes than my cnc machines. Both were dirt cheap to purchase. Rarely does a week go by that the manual machines sit idle. I have paid back the manual machines many times over, often on the first couple jobs.
Reply:Here is a interesting question that CNC guys can answer...Most of the lathes I see have a 6 jaw chuck..Run dead nuts I'll give them that..Even computer opened and closed...But.Can you manually adjust them if something is "Not Running True" like you can indicate something in on a manual machine with a 4 jaw chuck?...zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Originally Posted by zapsterHere is a interesting question that CNC guys can answer...Most of the lathes I see have a 6 jaw chuck..Run dead nuts I'll give them that..Even computer opened and closed...But.Can you manually adjust them if something is "Not Running True" like you can indicate something in on a manual machine with a 4 jaw chuck?...zap!
Reply:Originally Posted by Passenger6 jaw chucks aren't actually that common in the cnc world, if you see guys running them its usually because they are holding thin material that they don't want to distort. Yes you can run faceplates, collet chucks and 4jaws on the cnc. For jaw chucks the pressure is usually hydraulic and variable
Reply:Originally Posted by PassengerCNC, is better for everything, I don't have any manual machines, there is no reason to have one. I can make parts faster on the cnc's than manual machines, and they will be more accurate and have better finishes, not to mention tool life is significantly better.People who say otherwise just aren't competent on cnc machinery, simple as that.
Reply:I have used 6 jaw chucks on manual lathes for years and yes they are adjustable.  There are cap screws on the face and set screws around the OD.  Just indicate your part and use the setscrews to adjust.  Lock it down with the screws on the face.The argument between CNC or manual will allways be there.  Each has its good points.Russell
Reply:Originally Posted by zapsterHere is a interesting question that CNC guys can answer...Most of the lathes I see have a 6 jaw chuck..Run dead nuts I'll give them that..Even computer opened and closed...But.Can you manually adjust them if something is "Not Running True" like you can indicate something in on a manual machine with a 4 jaw chuck?...zap!
Reply:For novice machinists, I say exclusively manual.  The book may say to run brass at the maximum spindle speed, but things can happen pretty quickly if the machine runs on it's own at that speed.  For understanding of how machining works, manual.  For making money, CNC.  There are exceptions to both, but that's my general train of thought.