Is CNC cheating

Im of the opinion that if your loco or whatever is made from CNC derived parts then you cant in all honesty claim to have made them yourself. You may have designed and mounted the material yourself but it is the then automated machine which has made the part (I apreciate it isnt as simple as that!). I take total satisfaction from hand operating all of my machinery and wouldnt even dream of using CNC as it wouls remove all the pleasure and satisfaction for me. What do others think (and im not knocking those who do CNC their parts, each to his own).

The satisfaction derived from any activity depends on how well you meet your own criteria. For some model makers, it is a matter of getting as close as possible to the full size makers's design, methods, etc. For others it can be producing a model which looks the business, and for a third group as long as it goes along on its own they have met their own needs.

Whatever your aim, there are always (yes always) alternative materials (think asbestos, celluloid) and always corners that can be cut. If your aim is to avoid cutting corners, and you succeed, well done. For others, the joy is cutting corners and not getting found out.

There you are, a bit of philosophy ...

Cheers, Tim

I think that unless you cast your own metals, and hammer them into sheet if required ... there's a risk of "the Pot calling the Kettle black".

If someone gets pleasure from CNC-ing, then that's a perfectly legitimate version of the hobby.

... However, if the finished item is entered into competition; obviously the rules would prevail.

MichaelG.

I grew up as an engineer around an environment that had become heavily influenced by CnC machining, for a long time coming mind, and particularly G-code culture as i would call it. And even those who were the most skilled at it, admitted that you couldn't just know that and expect to be a competent machinist.

Knowing how to move the tools in a particular sequence isn't as ingenious as knowing how to create a jig or setup to get that same result, clearly the latter involved far more process and understanding in order to get there.

I mean, this argument isn't strictly limited to metal working, you could say it's all about where you draw a line between craftsmanship and simply being an operator for a computer program.

Also, there are plenty of occasions where you can't necessarily take a part to a machine and it must be dealt with insitue with hand tools.

I'm sure the blacksmith, the ironmonger, plate maker almost felt the same way about machines taking work away from him a few hundred of years ago now, it's come full circle and happening again with cnc. 

Michael W

Edited By Michael Walters on 31/08/2016 21:41:24

The desire to "not get caught" is almost an admission of guilt if you read a little further into that. So they clearly feel as though it was wrong to cheat in the first place.

Michael W

This isn't a new idea. I read somewhere that the original lathe cross-slide was disparagingly called 'Maudsley's Go-cart' by the old timers of his day. They felt that use of a cross-slide devalued the skill they applied to the job and that quality was reduced. It was cheating.

I think it depends on what you're doing and why. I admire and respect craftsmanship but it isn't my main goal not least because it's time-consuming. And I think learning how to apply CNC is itself a significant skill. I wouldn't knock either approach.

I suppose it would be possible for judges to weight competition scores according to the tools used, e.g

• Model made with hammer and cold chisel : x10
• Model made with hacksaw, file and hand drill: x8
• Model made with Chinese lathe: x7
• Model made with Western lathe: x4
• Model made with British Lathe: x3
• Model made with British Lathe and Mill: x2
• Model made with CNC: x1
• Model made using industrial machine centre: x0.5

Cheers,

Dave

I'm 100% with Fizzy on this, although I am not a model maker as such. I have a shop full of manual machines, and if they were CNC instead, I wouldn't bother going to work. If it is CNC, you didn't make it, the machine did. After all, you could load the machines, download the CAD/CAM , and let the machines get on with it. You could even take up another hobby in the time you would save! You would however learn very little, apart from perhaps how to fix recalcitrant CNC machines. After all, you can learn to load and operate a CNC machine very quickly, it is classed as a semi skilled job, but a proper toolmakers apprenticeship (if such a thing exists today) is seven years.

Phil

Phil,

I used to think I was a proper toolmaker , but I only did a 4 year apprenticeship, starting in 1970.

Having spent most of the last 2 days machining the inside connecting rod for my Gresley V3 tank loco I would willingly use cnc if I had a machine and the skill to use it. The skills needed to produce a 3D drawing and programme a machine to produce the required part are many, they are just different to those used on manual machines. Not better or worse just different .

Michael 

Edited By Michael Topping on 31/08/2016 22:11:55

Fizzy - (my oar is firmly in the CNC waters)

Q - if I make nuts and bolts on a CNC machine, from round rod, is that better or worse than purchasing the nuts from a model engineering supplier?

My goal is to purchase 0.0% of "finished" parts, just raw materials. IMHO, that makes my models my own creations. What do you think?

John.

(PS - and, yes, I do make my own nuts and bolts, as my stock of purchased ones depletes)

Edited By John Alexander Stewart on 31/08/2016 22:06:21

Is using castings for your loco etc, also cheating?

Martin.

I don't have any CNC machinery but I have seen some of the work it can produce and will admit it certainly has it's attractions where machining complex shapes are concerned. However, quite apart from the extra cost of equipment, having tried to understand some of the CNC articles I've looked at recently on the subject, it seems to me to require a good deal of expertise in it's own right - I don't think it's just click a mouse button and a "bit" magically appears... I'm pretty sure it still needs plenty of time and effort to master.

Last year I was involved in a collaborative effort to produce a small Gauge 3 locomotive. I did all the CAD drawings and made the running chassis for two engines. My co-worker made moulds from my drawings and produced two resin bodies to fit on my mechanical bits. Because the prototype 'source' information (a 100HP Sentinel) started out a bit scant but improved over time, I actually re-drew the prototype engine completely from scratch three times, with many smaller alterations in between. The final version was drawn from the builders GA plus selected photographs of some of the later engines. I spent very much more time on the CAD drawings than I ever did building the actual 'mechanicals' for the engines - and I've no real idea how long it took John to make the resin moulds and cast the bodies (which are really excellent by the way).

What I do know is that when I'm asked about the locomotive, it's the fact that it is an exact scale model (drawn full size and scaled to 1:22.6) that gives me the most satisfaction - possibly linked to the fact that it took me a great deal of time and effort to get them as accurate as I could.

So, I rather imagine that even if someone does just click a button and something gets "carved" as if by magic - that this was just the last part of what might have been quite a lengthy process and that probably quite a lot of time and effort had been invested before arriving at that point.

As for competitions - well provided someone is clear about how they've gone about the work and the end result is excellent - what's the problem?

Regards,

IanT

Obviously! As well as pressure gauges, safety valves, injectors, model plans, those new fangled electronic calculators, DROs, change wheels on a lathe for threading... probably even grabbing photos from the Internet to help you attain fidelity - what a boon that is for those of us modelling items from across an ocean.

(my first large lathe, which dated from the late 1880s, did not even have graduated dials anywhere on it, and it made quite a few parts... but I'm really glad to have the new machines)

John.

Totally agree with you about converting Michael,, but it is a different skill. Look at all the models made on early machines which probably had far less versatility than the manual machines we use. Maudsley chiselled and filed his early lead screws, then used them to make better ones on the machine, but he was still operating the machine. With CNC, the computer operates the machine, and the computer is totally stupid, as can be seen by some of the CNC crashes on many websites! I take your point, when you just have a job where you are hogging out metal to achieve a desired shape, the CNC is quicker, but needs a much less skilled operator, and most designs today are done direct on to the computer in 3d software. It just doesn't appeal to me one bit, but I am not working to a deadline, and I am not making 1000 off! Is your connecting rod job made harder because you are using a machine that is perhaps a mite to small for the job? I would bet there were no CNC machines in Gresleys day, and they were working 1:1!

Who cares?

I have a reasonably equipped workshop where I spend time enjoying myself. What I produce there is for my own satisfaction and , sometimes, at the request of others. If I saw a need to incorporate some CNC produced component ( so far I have not) then I would do so.

I have no interest in producing anything for a judge / competition - Indeed I find the concept of competition rather strange. I always try achieve the best result that I can ( with the " fit for purpose" criteria in mind ) .

A thought here - let's say a model is to be marked down for incorporating CNC components hence giving the user an unfair advantage .Should not a model made by a professionally trained toolmaker also be marked down as he will have an "unfair" advantage over " Joe Bloggs " who has picked up his expertise by reading ME and working it out in his shed?

Norman

When you use a DRO or a jig are you then not just a monkey turning the handle?

Just a thought.

Cheers Michael.

I couldn't care less how it was made, I just want the part in an efficient, timely manner. It's not as as if cranking handles on manual machines is a romantic mystical process tinged with magic. It's just work.

Hi Nigel,

I have never entered any of my locos in an exhibition, and do not intend to do so.

However the point you raise is highly relevant. The standard ME exhibition judging will cause you to loose points if parts are disclosed to be pre-made/pre-machined.

Some one who has hacksawed out their frames from plate will get more marks than someone who has bought CNC machined frames. The same can be applied to other parts, plus homemade as opposed to commercial fittings.

However someone who has done their own CNC programme or whatever is required might gain as much as someone who has cut them out with a hacksaw and filed them up.

Interesting debate.

Cheers,

Julian

Where do you draw the line? Most people building a model will use some bought in components eg. Castings, fasteners, rivets, laser cut frames or spokes. Often the task of making the boiler is contracted out. CNC exchanges one set of skills for another if you do your own coding. I feel comfortable that CNC can be used by the model builder and not declare that it is not his own work.

Mike