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I'm sure there's a dozen companies out there, but this is the one most of us will recognize:
http://www.rolanddga.com/solut...

What about the CNC services from King Roland?

They do have bigger machines.

Roland iModela.

This is bullshit.

First, copyright doesn't cover useful objects. Most of the "grey market" stuff is about brand labels, not the device itself. If you want a mechanical duplicate of a Rolex watch that doesn't say "Rolex", you can buy one legally. (You can even get the same movement made in the same Swiss factory. That's outsourced.) There's a whole third-party auto parts industry, after all.

Second, stereolithography machines are a slow way to make copies of something. Manufacturing techniques for making stamped and molded parts are faster, cheaper, and more accurate. You only bother with stereolithography or machine shop work if you can't buy the thing.

Third, a CNC mill can do most of the things a stereolithography machine can do, and to a much wider range of materials. There are little desktop CNC mills. Laser cutters, though, can turn out flat parts quickly and cheaply. This is why, at TechShop locations, the laser cutters are constantly busy while the stereolithography machines mostly just sit there.

Most of the clueless enthusiasm for stereolithography comes from people who don't do machine shop work.

It's not 25 000$, however you weren't far from the actual retail price (21 000$ USD for those interested).

It's easy enough to build a crap CNC mill, but not very useful. This one is made of wood, and the bridge isn't even cross-braced. It's not going to be stiff enough to do decent work. Just because the cutting tool is a Dremel tool doesn't mean you can skip on rigidity. Dremel used to make a drill-press rig for their tools, and it wobbled so much it was useless. And that was just drilling. In milling, you have side loads.

Little CNC mills have been around for years. Roland makes a nice little one. The usual little mill is a Sherline, and those can be equipped for CNC, although it's a retrofit. A Sherline can mill aluminum and mild steel. The MicroLux, at $499, is about as low as it gets in milling machines that can cut metal. That's not a CNC machine, but retrofits are possible.

These guys aren't the first to propose building a toy CNC mill. The Art Institute of Chicago has a little wooden CNC mill. And unlike these guys, who are peddling vaporware, the Art Institute machine exists. The Art Institute machine can be made from flat stock with a laser cutter. It can't mill hard materials, but if you're just making models of designs to look at, you can use various easy-to-mill foams, plastics, and waxes. A slightly bigger wood CNC machine is at Build Your CNC. Those are all proven designs.

Hype about CNC milling seems to be highest among people who've never used a milling machine. CNC mills are great devices, but they're not magic. The smaller machines don't cut very fast, the cutting tools are expensive, the process is messy (if you're cutting metal, you're constantly pouring coolant on the cutter, and in high-speed machines, the coolant flow is garden-hose sized), and for complex objects, clamping the work out of the way of the cutter is a hassle.

If you want to play with CNC on line, download the demo version of VCarve, which is a CAD/CAM design tool for 3-axis milling machines. VCarve will give you a sense of what you can and can't do with a 3-axis mill. VCarve can simulate the cutting process in 3D and show you what the finished part will look like. There's a really impressive solid modeling engine inside that program. VCarve (the pay version) will output the files to drive a CNC mill to make the part.

At the high end of CNC, there are 5-axis machines with tool changers, and software that can use all those features to full advantage. Watch this demo of Hypermill driving a Daishin 5-axis mill. The software package alone for that costs $20,000. The software figures out which tools to use in what order, and how much clearance is required to get the cutting head near the work. That's approaching the "replicator" level of CNC.

Now what would be interesting is to put a Dremel tool on a multi-axis robot arm, with force feedback from servomotors and Hypermill-like smarts. That would allow real 3D work, not just top-down 3-axis work. Most of the dumb 3-axis machines use steppers, so they don't know how much load is on the structure, and can't compensate for deflections under load. With servomotors, the software could compensate for some lack of rigidity.

Stereolithography machines aren't magic. They're a useful way of making plastic shapes in small quantities, expensively. But that's about it. Much of the same work can be done with a CNC milling machine. Roland makes some nice little desktop CNC mills. They also make 3D "scanners" which work by touch, carefully servoing a tiny stylus with a phonograph pickup like device over the surface of a 3D object. So you can copy existing objects.

All this stuff works fine, but it's a niche market. It's mostly used by people designing small, handheld devices.

Making plastic parts by injection molding, vacuum forming, or hot stamping is incredibly cheap and fast compared to building them up with a stereolithography machine. Making, say, a keyboard key in an injection molding press costs maybe a penny. Making one in a stereolithography machine will cost about $40. Yes, you can make one-offs, but not cheaply.

Realize that most manufactured goods (with the notable exception of wood products) are made by some kind of moulding process involving a master - stamping, casting, injection moulding, blowing and vacuum forming, etc. That's also true of photolithography, used for ICs and circuit boards. Building up something in layers or carving it out of a solid block costs orders of magnitude more.

If you want to use a stereolithography machines, and you're in Silicon Valley, sign up with TechShop. They have one of the better ones, plus workstations with the necessary design software. It's not used much. Their laser cutter, which cuts flat sheets, gets much more use.

Those are all professional grade machines, I never saw those before and thank
you for the link.

However have you ever seen the
stuff Roland puts out? They make a desktop CNC mills for under $1500
that can produce small items. Leases start at $100 @ mo. They have
desktop laser 3D scanners (put a real world object in, produces 3d model) too.

Does anyone know of someplace which is offering access to these printers to paying customers? I would be perfectly happy to email CAD plans to a fabricator if I could get a quick, cheap kit of parts back in the mail.

Buy your own machine. You said you're into modeling. That's what these are made for. Their smaller solutions are only a couple grand for a scanner & printer. Just over a grand if you only want the printer. Very cool stuff.

I mean it's not like this thing scanned in the broken pulley and made a replica based on the scan.

Probably not, but the Roland Picza will scan in smaller objects. You can then use their Modela to print out an exact duplicate. I saw a review of these products where they scanned in a little Yoda figure and printed out a copy. It was nearly perfect in every detail, save for the coloring... Best part: These things aren't all that expensive. A couple thousand dollars for both.

I mean it's not like this thing scanned in the broken pulley and made a replica based on the scan.

Probably not, but the Roland Picza will scan in smaller objects. You can then use their Modela to print out an exact duplicate. I saw a review of these products where they scanned in a little Yoda figure and printed out a copy. It was nearly perfect in every detail, save for the coloring... Best part: These things aren't all that expensive. A couple thousand dollars for both.

... a Roland MDX-15 for $3000, which is capable of similar feats, although on a smaller (6" x 4") scale.