How do you feel about using CNC?

[rleete]

Gotta side with Bogs on this one.

My job is a CAD designer. I sit at a computer and make pretty pictures, and the computer does all the tedious parts. I make a drawing, but it's for reference, as I send the computer files directly to the CNC to be made. If I've done my job and it's drawn correctly, and the CNC operator sets up the zero and speeds and such correctly, it will churn out perfect part after perfect part until the stock runs out. That may make for better profits and fatter bonus checks, but it ain't craftsmanship.

At home, however, I feel it's not quite kosher. Something about putting yourself into the metal. CNC is just too good, too easy.

 

[1hand]

CNC is just too good, too easy.

So is electricity............... everyone get out your files.

 

[mu38&Bg#]

We can do better than that! Use your treadle lathe to build an engine to turn your lathe.

 

[Troutsqueezer]

At work, I sit at a computer all day and use many different CAD programs (Ansoft, Icemax, Mentor, Cadence, Synopsis, AutoCAD and more, all geared to chip design).

At lunchtime I surf the web using my computer.

When I get home I read the news on my computer.

I watch YouTube videos on my computer.

I hit my favorite forums on my computer.

I do banking and investment portfolio upkeep on my computer.

I help the wife with her web site and garden club newsletter on the computer.

I email my friends and family on the computer.

I catch up on my favorite blogs on my computer.

On weekends I check the movie listings and restaurant menus on my computer.

I shop for things or research on what to buy on my computer.

When I finally make it out to the shop I'm tired of computers. *bang*

 

[NickG]

Gotta side with Bogs on this one.

My job is a CAD designer. I sit at a computer and make pretty pictures, and the computer does all the tedious parts. I make a drawing, but it's for reference, as I send the computer files directly to the CNC to be made. If I've done my job and it's drawn correctly, and the CNC operator sets up the zero and speeds and such correctly, it will churn out perfect part after perfect part until the stock runs out. That may make for better profits and fatter bonus checks, but it ain't craftsmanship.

At home, however, I feel it's not quite kosher. Something about putting yourself into the metal. CNC is just too good, too easy.

True to a certain extent, but I'm sure in the majority of cases CNC at hobby level involves a lot more. The CNC machine you send your CAD files to is probably pretty advanced, it must either know what the tool paths are, how much to take off in 1 cut etc, the machine won't know which features to machine first, the sequence of operations. It will have workholding and jigs to produce that specific component. The hobbiest will have to do all of this himself, so the only thing the CNC is doing for you is moving the handwheels to the right places. Also, in a lot of cases the hobbiest has converted his convential milling machine himself which is pretty impressive in my book.

As I said before, somebody mentioned DRO's they are about making life easier, more accurate and more features that can't easily be done - they are a computer, nothing else but I have nothing against them. Good point 1hand!

Dennis, I share some of those views too but I fear we'd be pretty lost without them these days.

incidentally, we do 3d cad models, then 2d drawings - and the setter then goes and inputs all the data from the 2d drawing into the machine!!

 

[Mainer]

Whatever floats your boat. The idea is to have fun in your shop. If you enjoy using CNC, go for it.

Personally, it doesn't interest me enough for me to want to get into it, though if I were younger and had more energy I probably would.

 

[peatoluser]

for people who think CNC is somehow cheating, then take a look at Clen Tomlinson's Deltic over on the internet craftsmanship museum
http://www.craftsmanshipmuseum.com/Tomlinson.htm

it's not the tools you use, it's what you use them to make that counts

we don't have this kind of discusion about people who use commercialy bought castings to produce great models (think, say, a merlin engine) so why think any less of work produced by CNC

 

[LongRat]

Most people would be happy to produce a hand-machined fixture or special tool to allow a specific machining task to be performed. As a person who built his own CNC mill, I view this as a somewhat advanced version of the same thing. You build a tool to achieve a goal.

 

[ieezitin]

An apprentice makes mistakes and does not know how to fix them, a journeyman makes mistakes but knows how to fix them, a master does not make mistakes.

The same rules apply to the computer machining group. Progress will march forward and will always prevail, but as Newton said “ where theirs an action there’s always a reaction, and history always seems to fade. You need both to be a master but alas in my eyes this is not the case today in this topic.

So! You have one side and then the other.

Anthony.

 

[Cedge]

As one who picked the hobby to help save an art that is in a death spiral, I have earned a deep appreciation for the skills and the talents of those who can manually force metal to their will by their very hands. The extensive knowledge base of centuries of labor and ingenuity is quickly slipping away as the old timers die off at an alarming rate. Fewer and fewer are learning the intricacies of the trade at a manual level and I suppose that is a natural product of technical advances required to compete in the marketplace these days.

I make no apologies for what has become a source of satisfaction that makes each trip to the shop an adventure. No computer can replace the enjoyment I feel in guiding a cutter into the metal and knowing when to withdraw it for a perfect cut. I truly enjoy the physical act of creation that manual machining allows me to be a part of. I most admire the finished products of those who can producing a perfect part by hand. If that makes me old fashioned, I'll wear the badge with honor, as I try to emulate those I've come to admire.

No beef with those who get a similar thrill from directing a computer to do their will. I've been doing that for more years than I like to count. There is no disputing that CNC is the future or that manual operations are fast becoming relics of the past. A talented manual machinist will someday be a much desired commodity, simply because there will be so few of them to be had. If for no better reason than "just in time" manufacturing practices that eliminate replacement parts being stored on site, to repair the new fangled computer driven machines that can't be economically taken off line to make a one off replacement gear or bushing. That's when old school guys like Rick (rake60) make their real value known.

Every engine I've built has a little of me in it. They simply aren't happy until they've extracted at least a small toll in blood. Small payment for the enjoyment their first successful run provides me. CNC if it gets you there, or manual if getting a bit of DNA into the project is your nirvana. Either process can be a labor of love.....eh?

Steve

 

[shred]

I was reminded me of something that may not be clear to everyone thats not been here a while-- engine-making at the hobby CNC level, you aren't making the entire engine or even an entire part on the CNC; there's a whole lot of work and parts and operations that are done manually. It takes an ok-to-decent machinist to get anything good out of hobby CNC machines (I suspect this is why there are a group of people that spend all their time fiddling with their CNC, not making parts-- they skipped the learn-to-machine-by-hand step)

Take, say, this embryonic flywheel:

The spokes are CNC-ed, the rest is old-school sawing, turning (friction turning!), milling, drilling and press-fitting a hub. Is it a modified CNC part? CNC-ed manual part? Would it be different if it was a raw casting?

Anyway... some are more about the journey, some more about the destination and I don't see that changing anytime soon, nor do I want it to.

 

[milotrain]

An apprentice makes mistakes and does not know how to fix them, a journeyman makes mistakes but knows how to fix them, a master does not make mistakes.

The same rules apply to the computer machining group. Progress will march forward and will always prevail, but as Newton said “ where theirs an action there’s always a reaction, and history always seems to fade. You need both to be a master but alas in my eyes this is not the case today in this topic.

So! You have one side and then the other.

Anthony.

This is especially amusing when thinking about the CNC fail videos on youtube. With great power comes great responsibility. I don't think you could ever hurt a machine by hand as much as some of those poorly coded failures did.

 

[Iffy Boat Race]

I tip my hat to the guys that were trained to machine things the old school way.It is sad to see a lot of handskills to fade away and its sad to see the true craftsman become rare breed...CNC is here to stay ( i get to play with a CNC lathe at work).
It is great to see an old fashioned Craftsman ply his trade.

 

[Tin Falcon]

Brings to mind the classic quote : " To err is human, to really foul things up requires a computer"
Tin

 

[jpeter]

Here's a flywheel I cnc'd. I feel I'd be getting more respect as a machinist if I'd have manually machined it in a rotary table such that it had sharp or chamfered edges and step down 2D spokes, or maybe no spokes at all, instead of CNC computer generated eliptical tapered spokes.

 

[GWRdriver]

engine-making at the hobby CNC level, you aren't making the entire engine or even an entire part on the CNC; . . . Take say, this embryonic flywheel: . . . Would it be different if it was a raw casting?

Shred,
As I said in my first post . . it is a slippery slope.

 

[wareagle]

jpeter, nothing to sneeze at there! Nice looking flywheel! :bow:

 

[cfellows]

As my Mama used to say (sort of), anybody who's sneering at your CNC produced work is probably just jealous because they don't have a CNC set up! I know I am.

Chuck

 

[joe d]

Here's a flywheel I cnc'd. I feel I'd be getting more respect as a machinist if I'd have manually machined it in a rotary table such that it had sharp or chamfered edges and step down 2D spokes, or maybe no spokes at all, instead of CNC computer generated eliptical tapered spokes.

Jpeter:

That's a perfectly fine looking flywheel, and I personally don't care how you made it, it suits the engine.
You have my respect for a job well done. Looking forward to seeing more, no matter what machining
procedure you use to achieve it.

Cheers, Joe

 

[doc1955]

Whatever floats your boat. The idea is to have fun in your shop. If you enjoy using CNC, go for it.

Personally, it doesn't interest me enough for me to want to get into it, though if I were younger and had more energy I probably would.

I agree with what you have said we are doing this (least wise I am) for pleasure and unwind time so if you enjoy cnc and can swing the cost by all means. To me it matters not how a project is done.