Is CNC cheating

[MWParticipant @mw27036]

Posted by Neil Wyatt on 01/09/2016 08:28:12:

It's rather like a painter saying photography isn't art.

Neil

Cue, the stuckists! They don't like them city folk.

Michael W

[MWParticipant @mw27036]

Posted by JasonB on 01/09/2016 14:47:47:

It would be interesting to know if Fizzy thinks it is cheating for model engineering only or all forms of home shop machining?

It would be unwise to suggest interest when the following statement leads to infer ridicule or hypocrisy. I should not take that as meaning sincere interest.

Michael W

[SillyOldDufferModerator @sillyoldduffer]

Posted by Michael Walters on 01/09/2016 15:51:09:

Posted by Neil Wyatt on 01/09/2016 08:28:12:

It's rather like a painter saying photography isn't art.

Neil

Cue, the stuckists! They don't like them city folk.

Michael W

Many thanks for Stuckism – my latest word of the day.

Cheers,

Dave

[Speedy Builder5Participant @speedybuilder5]

So I suppose that if you CAD design your model and outsource the CNC machining, then you would have made it yourself. Its a bit like buying nuts, bolts and springs and saying I made it all myself. I would think that judging at competition level will become even more difficult if we try to differentiate the different types of machine we use. Its a fact that we can't all afford the latest techniques and we should enjoy what we can afford and use and enjoy the hobby. For me, I have total diss interest in prizes and judging, but if a small write up of what was used to make a model was beside the model, it may encourage the less tooled up members when they see a model made by a hacksaw, file and pillar drill etc etc.
BobH

[MWParticipant @mw27036]

Lets presume we can all play god for a second, and anything you wanted to build; you could have, how long would that novelty last? Would you really call that a skill, just demanding something and it's done? 

You would eventually reach a point where nothing would be of interest to you anymore because there was no challenge to set your eyes onto. So yes, i think the challenge of the process is part of what makes model engineering so interesting.

The CNC part of the argument, is simply a vehicle for a much deeper question about whether we apprieciate it's manufacture as a skill. Nobody would argue that cnc can't be difficult and challenging at times. They aren't attacking you for that. 

The real reason for it is almost a prescient fear of the unknown, when do we reach a point when we can just demand anything to be made exactly to our requirements and not lift a finger to do it? Are we ready or mature enough for that kind of power? That, ladies and gentlemen, is the source of the concern. CNC would be just like anything else if it wasn't for it's hidden potential, "plain ol' plain Jane humdrum C'n'c",  a sense of whether something has been earned, or fairness. 

Michael W

 

Edited By Michael Walters on 01/09/2016 16:25:06

[Phil WhitleyParticipant @philwhitley94135]

Posted by Bandersnatch on 31/08/2016 23:07:11:

Posted by Phil Whitley on 31/08/2016 22:21:42:

Totally agree with you about converting Michael,,

Don't worry, Phil, we'll figure it out. There are only 5 Michaels contributing to this thread so far.

Sorry, my bad, it was to Michael Topping.

[Phil WhitleyParticipant @philwhitley94135]

Nicholas Wheeler 1

It's not as as if cranking handles on manual machines is a romantic mystical process tinged with magic. It's just work.

?

Perhaps I am weird (some have said it!) but that is exactly the opposite to how I feel when I am machining! Perhaps Nick needs a different hobby!

Phil

[Old SchoolParticipant @oldschool]

I build and race tethered cars, the only measure is the speed you achieve apart from passing scruteneering. I use whatever technology is available. My workshop is manual but if I can get a part cnc machined chassis I do, for welding up tuned pipes I use a local specialist tog welder etc. I don't consider myself a cheat and many would not consider me a model engineer. But I enjoy the competion with fellow racers.

[Roderick JenkinsParticipant @roderickjenkins93242]

Posted by Hopper on 01/09/2016 14:19:32:

I'm not so sure on that Rod. Keeping on going for eight more cylinders and keeping up the concentration to get them all as right as the first one is a skill on its own.

That's the skill they were teaching apprentices back in the day when they made them file 4" square blocks of 1" steel steel plate perfectly flat and square then cut a perfectly square hole in the middle of it and file another block to a perfect fit in it.

By the time my younger brother came to do his apprenticeship, the cheeky blighter used to jump on the surface grinder while the apprentice instructor was away at lunch and knock his steel block down nice and flat then throw a few draw file marks on it for good measure. He got full points for the finished product. Some would say he cheated. He says he got the job done, the smart way.

Keeping on with dogged determination is certainly an admirable quality, but a skill?

Your brother's behaviour is interesting. If the idea is to pass an exam, then yes, he cheated since he has not demonstrated the ability to file a cube. He has also cheated himself since he did not take the opportunity to learn how to file like a craftsman.

But, unless we home engineers are entering competitions, then there is no arbiter on what is right and what is wrong but oneself. I think Andrew's response is a bit harsh: it's only a debating point. Unless, of course, Fizzy's original comment was meant as a "I'm holier than thou boast", which I don't think it was.

We could (and probably will ) debate this forever, for I don't believe there is a right answer.

Cheers,

Rod

[Jon GibbsParticipant @jongibbs59756]

I don't know about you all but I see this as a "tool-envy" issue as much as a point of principle. None of us really make everything and if we're honest we all use the most appropriate tool we have to get the job done better, quicker or easier.

I'd love a Bridgeport Mill with power feed, a decent big capacity lathe with power cross-feed and a tracing attachment, a pantograph engraving machine and a surface grinder and a CNC mill or the time and money to build one but I've got none of them. I've got an old Myford and an old round column mill and I enjoy using them and making things within mine and their capabilities.

…but hats off to those who have the time and money and especially those who can persuade their other halves they're worth it

…and it doesn't matter what you've got there'll always someone better equipped than you.

…Get over it!

Jon

[mickParticipant @mick65121]

I'm an old G code man, I don't have CAD/CAM as I don't know how to use them, all my programs are hand written, I do now use the computer to work out the trig these days, so is CNC cheating? not if you use G code it isn't!

[Nick WheelerParticipant @nickwheeler]

Posted by Phil Whitley on 01/09/2016 16:46:14:

Nicholas Wheeler 1

It's not as as if cranking handles on manual machines is a romantic mystical process tinged with magic. It's just work.

?

Perhaps I am weird (some have said it!) but that is exactly the opposite to how I feel when I am machining! Perhaps Nick needs a different hobby!

Phil

I use small machine tools(and welders, hand tools, etc) at home to make and repair parts for things to support my hobbies. Bizzarely 'Model Engineer' has become the English term to describe this; the American 'Home Shop Machinist' seems so much more sensible to me. Being able to produce the part is what matters to me, I'll cut and file a small piece, but I've also drawn them in CAD and had them laser cut when it's been a better solution.

I started with a mini-lathe, then bought a mini-mill. A couple of years ago I upgraded to a WM250v lathe and the ability to easily take 3mm cuts in steel has dramatically improved my productivity. Doing the same with the mill would probably be even more effective, but I simply don't have room for anything bigger. Converting it to CNC so it cranks to and fro shaving off little bits of metal while I do something else could be almost as good.

[EmgeeParticipant @emgee]

mick

I'm also a G code man, but if cnc is cheating I must be a bigger cheat than you as I also use a few M codes. !!!!!!!

Emgee

[Iain DownsParticipant @iaindowns78295]

The most satisfaction I've had in my (short) model engineering career to date is after I'd machined a motor mounting plate for a CNC conversion on a tiny mill fitted with a previous version of the conversion.

In the process, I'd designed (and redesigned) the motor mounting system and gone through 3 sizes of motor (cut and try!), built the electronics to control them (admitedly from modules), written an arduino program from scratch to drive the motors, invented my own G-Code like language to run on the arduino, built a PC program to drive the arduino and written an 'Iain Code' script to carve out the mount.

I would refute any suggestion that machining the mounting plate was cheating, given how much 'proper' engineering it took to get me to that point! I use the term 'proper' in my case with tongue firmly in my cheek!

I shall derive even more fun from improving the CNCness of my mill. I still have to add a Z axis, make the mill more accurate and I have a revised version of 'Iain Code' and driver in the pipeline.

Iain

[duncan webster 1Participant @duncanwebster1]

Posted by Michael Walters on 01/09/2016 08:23:27:

Posted by Hopper on 01/09/2016 07:20:06:

Electric motors! That's where the rot set in! If you don't treadle it yourself and soak the job in your own sweat, you haven't really made it yourself!

Yes! I knew they were the work of the devil! Them motorcaring city folk just don't know whats good for em anymore.

Seriously though, if i can teach someone with no machining experience to run a cnc program, then surely, even the proponents have to tell you that there is obviously a descrepancy between the two. You can't argue they are equal skills.

Michael W

Edited By Michael Walters on 01/09/2016 08:27:19

But I can teach someone with no machining experience to drive a manual machine tool. I see no intrinsic difference between twiidling a handle so many turns plus so many divisions and telling the computer in G code to do it. You still have to know appropriate speeds, depth of cut, feed rate etc, and don't think you can just let the machine get on with it under computer control with an unskilled man supervising, seen what happens when the unskilled guy didn't know it wasn't supposed to make that noise, ruined tens of thousands of pounds worth of components. Sensible management puts skilled guy on, just gets more productivity.

I presume all the naysayers refuse to use the leadscrew when screwcutting, as that would be taking the skill out of it.

[Ady1Participant @ady1]

I presume all the naysayers refuse to use the leadscrew when screwcutting, as that would be taking the skill out of it.

Hand chasers only for the highly skilled boys, much faster for producing threads too

Don't know if anyone who did that is still about though

[Neil WyattModerator @neilwyatt]

Posted by Ady1 on 01/09/2016 21:13:19:

I presume all the naysayers refuse to use the leadscrew when screwcutting, as that would be taking the skill out of it.

Hand chasers only for the highly skilled boys, much faster for producing threads too

Don't know if anyone who did that is still about though

I had a try.

I didn't feel the need to share the results

[Ian PParticipant @ianp]

Posted by Nicholas Wheeler 1 on 01/09/2016 17:51:23:

Posted by Phil Whitley on 01/09/2016 16:46:14:

I use small machine tools(and welders, hand tools, etc) at home to make and repair parts for things to support my hobbies. Bizzarely 'Model Engineer' has become the English term to describe this; the American 'Home Shop Machinist' seems so much more sensible to me. Being able to produce the part is what matters to me, I'll cut and file a small piece, but I've also drawn them in CAD and had them laser cut when it's been a better solution.

I started with a mini-lathe, then bought a mini-mill. A couple of years ago I upgraded to a WM250v lathe and the ability to easily take 3mm cuts in steel has dramatically improved my productivity. Doing the same with the mill would probably be even more effective, but I simply don't have room for anything bigger. Converting it to CNC so it cranks to and fro shaving off little bits of metal while I do something else could be almost as good.

I sometimes find myself telling people I am a model engineer in spite of the fact I don't make models but it is the easy way to explaining what sort of workshop I have.

Ian P

[Gordon AParticipant @gordona]

To some, it's not so much the destination that matters but the journey undertaken to reach there.

Horses for courses at the end of the day.

Gordon.

[Neil WyattModerator @neilwyatt]

How can you cheat at something that is non-competitive?

N.

[John Stevenson 1Participant @johnstevenson1]

When I first got into CNC many years ago as both a builder, converter and user it was a steep learning curve which gradually levelled off with the help of better software.

Without bragging I have probably done more cnc’s than anyone in the UK. I developed the X3 kit that ARC sold so successfully until Sieg, who we worked closely with, introduced the first Turnkey CNC’s into the UK and America.

Because of this background and the exposure we had at shows and the talks we gave at shows and some clubs this subject is one that raises it’s head with regular timing.

There is no one stock answer because everyone who has posted on here is talking about themselves, no one else and whilst they may not realise it it’s a selfish attitude where the next person isn’t taken into account.
When I used to stand up and give one of these talks and probably some on here have attended them?, they used to be full room talks which says more for interest in the subject than my charismatic presentation .

Standing up and addressing a full room means you you have to appeal, or try to to the whole room. Luditesand the unwashed included.
To this problem I made a list of 10 reasons why CNC might appeal.

This started with lack of formal training and apprenticeship to newcomers to the hobby having more computer skills than manual. This lead on to a CNC supporting another hobby like vintage bikes, just needing the part no matter how made thru to the last reason.

This was surprising in that for some people CNC had now become their hobby. The MKl making the MKll etc

[thaiguzziParticipant @thaiguzzi]

I am a Luddite, and used to be unwashed and proud… Now i'm married i'm still a Luddite, but unfortunately now un-unwashed…

[Neil WyattModerator @neilwyatt]

I've been thinking about this quite a bit.

The comments of those denigrating CNC really seem to think it is like using a bread maker. You throw in the right quantities of steel, brass and cast iron, turn the dials to 'Loco'; and '5" gauge', then press 'GO'.

The core of this is Fizzy's claim that CNC is 'cheating'; cheating requires deceit so for a start you can't be cheating unless you claim CNC-made parts were fashioned manually. I'd be 'cheating' if I claimed the loaf from my bread maker was a hand-made artisan loaf. Now I find kneading dough as therapeutic as the next fool but I'm rather glad it's no longer a daily chore and don't think it's cheating for me to use the bread maker if I just want a loaf of nice, fresh bread.

WHERE THE EFFORT LIES

The same amount of effort is put in, but like many things in the 21st century there's more mental application required and less physical.

If not going into competition, they how can people be cheating? If entering a competition and declared it is hardly cheating either; indeed the CNC user should get some credit if they drew up the plans themselves rather than downloading them – just as I hope I get credit for making patterns for the castings for a model even though someone cast the parts for me.

WHEN IS THE SKILL LOST?

I admit to enjoying the process of cutting metal with a machine under my direct control, but having spent a couple of weeks testing a power feed on my mill I'm getting used to it. I have a pile of 13 change gears and counting, even in nylon the endless handle turning would have meant much slower progress.

In the old says someone did exactly the same job (in brass not nylon) indexing with Myford change gears and using a super-duper Adept as a shaper. They used an optical projector to hone their cutter to shape.

I ground up a 20-degree tool and made a rack-form cutter out of silver steel. Even the 20-tooth gears run smoothly and appear indistinguishable from moulded ones.

I used a spreadsheet to tell me how to set the dial on the rotary table. I could have made and used division plates or worked it out in my head.

I could have used the dial to set the DOC was exactly one turn (1.50mm) after allowing 0.01mm for winding in until the cutter touched the work. But it's easier to see the DRO when sitting down than to take my glasses off and peer over the handle.

It isn't hard to imagine an automatic arrangement where the mill table winds the cutter past the blank and then back again. That would have stopped my left wrist getting sore from being awkwardly posed over the reversing switch.

I could add a stepper motor to turn the rotary table and have avoided several; scrappers where my eye fell on the wrong line of the spreadsheet.

This would totally automate the process, but still isn't CNC – setting two travel stops then having something generate X pulses every time one of the switches is triggered isn't 'computer numeric control'.

That said, moving to full CNC would replace the switches with virtual ones and give me a more flexible interface.

So at what point on the route from shaping brass gears by hand to CNC does it become cheating?

To my mind the critical point where the skill required dropped was when I chose to use the multi-point rack cutter method. Having made lots of gears using single point cutters the rack form one took less than a quarter of the time to make and less skill; I also only need one to cut both 20 and 80-tooth cutters, rather than having to make a set.

Counter-intuitively, making the gears wholly by CNC would probably require greater skill. There's really barely any skill in the mechanical method other than getting the DOC and angular turn correct – with the rack method you don't even have to have the cutter exactly on the centreline of the blank to get usable gears.

WHY IS CNC DIFFERENT FROM OTHER AREAS OF PROGRESS?

I have made a box, effectively just like CNC, and once I have set up my telescope (which requires as much skill or more as setting up to take a cut, it will point at what I want to photograph and follow it (Interesting point – I set the roatry table to an accuracy of 10 arc-minutes, the scope demands arc-second accuracy). A little controller takes 120 pictures for me. A computer program chooses the best of these and stacks and averages them. I then spend time processing the image, aided by some automated scripts and advanced filters.

I was looking at an old coffee-table book yesterday, it had a picture of the Andromeda Galaxy taken by the Palomar 200" telescope. The core was burnt out baldy, and although the greater aperture meant the surrounding stars were a bit smaller and sharper, there's vastly more detail in the pictures I took last week.

Quite simply, without the help of computers it would be impossible to produce an image of that quality (and by the standards achieved by others it is far from remarkable). Yet by the arguments above it is clearly 'cheating'.

… to be continued

[Neil WyattModerator @neilwyatt]

Part the second…

SO IS CNC CHEATING?

No it isn't cheating to use CNC – only if you don't explain what you are doing, which is no different to declaring bought-in parts or where someone gave you a hand with painting or an oversize part.

I think the real problem is the 'Palomar Effect'.

Those who achieve things by manual skill and dexterity fear that those with CNC will produce better work than they could ever achieve and that when judged side-by side with the product of the CNC user will be deemed to be superior. And if the person has skills developed over a lifetime of manual machining, they fear that someone with few skills but having a 'magic box' can make their work seem crude and unfinished.

So at the bottom of all this is suspicion, fear and jealousy. Suspicion that people will 'cheat' by not declaring they use CNC; fear that their own work will be less appreciated or valued; and jealousy that those less skilled can achieve better results with less effort.

The answer to all these is for everyone to be open and transparent about the methods they use, a long standing tradition anyway; to value and evaluate work in context; and to appreciate where the skills and effort lie in every piece of work.

Neil

[Mike PooleParticipant @mikepoole82104]

If Shaun Wainford was making his Barbarian Motorcycle by hand I think he would still be a long way from completion. The great thing about CNC is that it pushes the boundary of what can be made on a mill or lathe. I don't have any CNC equipment at the moment and enjoy hand control but power feed is close to being fitted as this produces a better finish than I can, even when I concentrate. I once watched an NC Marwin make a 2ft diameter turbine, it took about six weeks to make. That was 38 years a go, to make it by hand the customer would probably still be waiting.

Mike

Edited By Michael Poole on 02/09/2016 10:00:27

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