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Comment by aortega | Hacker News Reader

IMHO 3d-printing is way overrated. We already have CNC machines that are reliable, faster, cheaper and more capable than 3d-printers, in that they can cheaply "print" in hard materials like metal with much better resolution. What are the advantages of 3d-printers? (except than being slightly more clean)

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There are shapes you can achieve in 3D printing that you can't with CNC machines. Waste material is a significant problem if you were to have a machine on your desk or your living room.

Another advantage is that 3D printers actually have a community around it and people pushing its boundaries, as well as new companies forming in the space to push the tech forward. That's bound to make it better--or at the very least, explore what's possible. I don't see the same thing happening with CNC machines. No new CNC machine startups that I hear about.

I can see that unlike a 3d-printer, it's impossible to have a CNC in your desktop because of the waste. But I don't buy the "community" argument. Community has given us things like the arduino, a horrible technology obsolete from the very start. I do not think a technology is better just because many people use it.

Perhaps I should have been more clear. The 3D printing community actively trades tips on how to make their printers better. The hobbyists and certain 3D printer companies alike embrace open source hardware. It is this activity within a community that helps them make progress.

Are similar things happening in CNC machining communities? From my vantage point, it doesn't seem like it.

Cnczone is pretty cool as a community, but I do think the reprap community is more helpful by an order of magnitude. Having met many members of both groups in real life, the reprappers are generally more approachable. I get the impression that every CNC build is a custom design "because I can" whereas most reprappers tend to stick to a few common designs and possibly modify them. Modifications that work generally spread back to the community really really fast and improve life for everyone. The #reprap IRC channel on freenode is an absolute goldmine of a resource, people with questions or problems generally get answers within seconds and it's active, fun discussion the rest of the time. Haven't seen anything equivalent in CNC (cnczone comes closest).

What do you suggest in arduino's place?

Raspberry pi. Or better, the new beaglebone black. Anything with more than 10 kb of ram, really.

I don't think you can compare RPI to Arduino at all. Arduino is certainly not an obsolete technology. There are lots of projects where prototyping with an Arduino and finishing the project with a super cheap AVR chip is the way to go.

Yeah, the only interest I have in consumer 3d printing is to prove parts will work correctly; anything I care about needs metal. The metal powder stuff isn't really that exciting yet, either.

Quiet. Simpler to operate. And don't kid yourself that you can use a desktop CNC to work with metal. Even aluminium requires a $10k+ CNC with steel frame, cooling liquid, etc.

Sure, but don't kid yourself that you can use a cheap 3d printer to work with metal either.

aluminum is not bad, you can cut it with woodworking tools like routers and dremels, though not very well. Steel is the real test.

You can take a sub-$1000 benchtop mill (Sieg X2 or X3, for example), add less than $1000 of new parts and less than $1000 worth of motors and electronics, and have a benchtop CNC mill capable of working with aluminum and brass with no problems, and with steel in light passes.

If you don't want to do it yourself, you can buy complete from-the-factory benchtop CNC mills (Little Machine Shop: $4500, Tormach: $6k-$8k). If you don't need the size, you can get desktop CNC mills, "ready to run" for about the same price as doing it yourself (Sherline: $2k-$3k).

The only way to have good results with metals is to back it up with a huge mass. So Tormach will work. Everything else, that you've mentioned would not. Ask me how I know... But Tormach puts you at least 6.5k behind. Add tooling, table, box to keep the dust out, soundproofing, vacuum. Add PC, monitor. And CAD/CAM software. And you are looking at 10k.

I've done the first, and get good results with aluminum, brass, and both mild and stainless steel (although stainless is probably pushing the limit here). Your anecdote + my anecdote don't equal data, but your use of absolutes -- specifically "the only way" is incorrect. It can be done, and many have done exactly that.

Also, your magic $10k price-point mill doesn't include the cost of tooling, or workholding, or CAD/CAM software, etc. So now you're just reaching for anything to inflate the cost back up to your number.

People like the idea of 3d-printing because the dream is that you could print any material, and you would not have the limitations CNC has due to angles and bits.

That's the dream, of course. It isn't really a reality yet.

Oh, and CNC machines are big an expensive. Again, people dream that 3d-printers will be smaller, cheaper, and even faster.

I just wish CNC machines would get some press alongside 3d printers, then maybe some better kits would materialize.

Cheap CNC machines are about the same price as 3d printers now.

word

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