Shoot. I was looking forward to trying this.

You're definitely correct. If someone thinks this machine will perform magic they are obviously wishing away reality.

Have you seen what Kinect can do with 3d analysis? Kinect + 3d extruder could do a lot of fun stuff. Most of it wouldn't be useful in a practical sense but you could start making sellable art with this technology. scan yourself with kinect and print an action figure of yourself.

Their Mantis bot looks inviting at first: $100 DIY CNC.

At closer look, that's $100 without the electronics, and you need to cut the wood yourself. The DXF file provided on the website is incomplete as is the BOM.

I was originally looking at building one of those but after realizing how open-ended the work would be I've moved onto the idea of getting a kit. This CNC looks perfect for me and is the cheapest option.

You have it wrong.

You pledge to support X dollars. Depending on your pledge, if the funding reaches it's goal, you get the CNC. If the funding doesn't reach it's goal, you pay nothing.

So you decide what you want (just the plans, the electronics, the entire kit, or a preassembled unit), pledge the right number of $ and select your reward.

You aren't giving them money for nothing. Consider it a preorder system where you don't have to pay unless they get enough orders.

Please elaborate and include alternatives at a similar price point.

Depends on your use case. Someone trying to reproduce parts for their car at first step is probably going to fail.

I want one for milling circuit boards and aluminum panels for synthesizer modules. A small machine like this is perfect for me.

For 3D replication, look at what the Kinect can do. It's only a matter of time before someone finalizes a 3d scanner with kinect -> print with a 3d extruder.

It could be done but a lot of the cheaper devices have the lead screws bound directly to the motors with epoxy. So you can't really swap out the axis motors that easily. The spindle seems easier on a lot of designs though.

Seems like most people after building one machine, eventually build another, and another :) They're complimentary, once you have one you have the main tool needed to build another.

You are definitely correct, however...

I've been researching these for the last month, and what I found is that there are similarly functional kits available that would work out to be about $600 apiece.

Alternately people have been building them from scratch for about $200-$300. While you use the parallel port for I/O you need a stepper driver board to provide the voltages necessary to drive the stepper motors. A quality board like that costs over $100 on it's own. You need to figure out the math for the power supply to provide the right voltages to your motors, the right parts, a workshop for cutting them, etc, etc. It's a huge undertaking in time.

This is the cheapest option for a complete kit at your door. It's also the cheapest option at $520 for an assembled unit at your door.

If you posted on the reprap forums very likely you could find someone in your area with the means to print objects in 3D.

They haven't gone after reprap or any of the other more expensive hobbiest options for a CNC or 3d printer like makerbot, zen toolworks CNC, etc, etc.

You will probably see legal action when 3d designs start showing up on bittorrent :)

I believe one of the issues is you design a mill for power, and an extruder for speed.

The drive electronics can't really be both. For a hobbiest it shouldn't matter too much though, your designs will just be created slower.

I trusted it enough to back the $390 for a kit.

I emailed the creator and he was very quick to respond, and seems very genuinely excited and interested in this project.

I agree there is definitely a risk in the project since it's not proven, but after contemplating it I decided to take that risk.

With a relatively modular design, it would be simple to interchange the drill for a 3d extruder.

This would then be able to work as a 3d printer like the Makerbot, or RepRap.

Depends on what your goal is. There's plenty of free 3d modellers, plenty of free or cheap PCB routing software choices.

For actually controlling the mill, in linux there is ECM2 which is a robust platform. http://www.linuxcnc.org/

For PCB design there are a ton of choices but a popular hobbiest choice is EAGLE from CADSoft.

In the future there will probably be a repository of available plans for download anyways, so people will be able to mill and print items without the need to design them first.

This is the cheapest path for a CNC and 3d printer in every home.

I have done quite a bit of research on it and it's competitors (Zen Toolworks CNC, Mantis CNC, Makerbot, Cupcake CNC) and none lead to a completed kit for this low of a price without serious time investment, trial and error, and knowledge.