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Drill Press Info
I'll second on the Jet. I've machined on Jet mills, own a jet lathe, and also own one of the grizzley imported mini mills which I converted to CNC. Once I finish building my house, I'm going to look for a big blown bridgeport CNC and update it, but I just don't have the space now.
The finish all in all on the Jet is not bad, and it does the job great. As far as imports go, the Jet is much better quality than my grizzly or harbor freight equipment. Still not as nice as something like a bridgeport, but for my hobby machining, it's way overkill.
The benchtop and mini mills cost more than a typical drill press, but you can definitly get the slow RPM's if you need them, and the setup and accuracy is nice. The quality of my work went up 100x when I started using machine tools. It's getting even better as I learn to be a "real" machinist. So much to learn!
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I should qualify my grizzley equipment - I bought the smaller end of their mill series, and while the quality was OK on it, my Jet lathe (mid size) was nicer.
I've put 3000+ hours on my mini mill (CNC makes it very easy to do that!) and I can't complain. I've had to replace the brushes several times, and it's probably time for a new motor, but if I compare all the cash I have in it ($600 for the CNC stuff and $500 in the mill) then I've got only a few cents per hour use... Even when I get bigger equipment, I'll still probably keep it. Easy to run, easy to clean, and easy to setup. I've built jigs for it for doing things like electronic chassis backplates and the like. At times I was making 50 backplates per night after I got home from my real job.
That said, when I do have the space, (and recover buck-wise from building a house!) I wouldn't hesitate to buy grizzly again.
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Here is what I did - I added some of my own circutry and modified the software a bit for my own hardware, but it really is pretty easy to do.
First, take an old pc, but preferably one with decent quality RAM/motherboard, that has a printer port. Install linux and the EMC (embedded machine control) software. EMC and linux used to be tough to install, but nowadays, you can download a CDROM image called the BDI disk for it (BDI = Brain Dead Install). Wire up stepper or step/dir servo drives to the printer port, along with Estop and home/limit switches.
For motors/drives, I used ebay DC servos with encoders, and the geckodrive servo drives. (www.geckodrive.com) - Mariss, the owner/inventor of the geckodrives is coming out with a new piece of drive hardware that will connect via USB and do the step generation for up to 6 axis and connect to the drives, eliminating the parallel port need. Support for linux should be available with the G2002 (new hardware) is out, but in the interim, you can just use the printer port and let EMC generate the pulses. I really can't say enough good things about the geckodrives. Easy to use, work great, fault tolerant, and for the most part, idiot tolerant. Somehow I blew one up, and Mariss generally fixes one for free. I sent mine in, with a note, and he sent it back fixed. There are cheaper ones, but none that are as professionally designed and built. He sells them direct; He has his own smt production equipment and makes them right there.
I overbought on the servos so that I can use them with a bigger mill someday, and have the whole works wired up in a 19" rack enclosure. Boot the PC, load your .g code files over the network or from a floppy (from your cad/cam software, or written in a text editor), and hit go. It also works great for manual work, using a joystick, since you can watch the display for your measurements. My system even turns on the flood coolant, and starts and stops the spindle when the operation is complete. I don't have a tool changer, so I generally break my work into phases by tool, or just use a generic enough end mill to get the job done.
EMC is free, but there are turn key pay solutions. I prefer linux and EMC myself - For example, My fleabay encoders had very high resolution, so high that I needed an insane step rate to get decent feed speeds. (The gecko can work around this, but my early version of the drive didn't have that feature). Since I had the source code, I simply added a 10x pulse multiplier in the "output" routine, and for my work, at my rates, it works fine. (Technically I'm screwing up the velocity of the endmill slightly, but the machine does fine work). EMC takes a bit more reading to get running than the out of the box ones, but it is more flexible, and in fact, a lot of commercial software borrows heavily from the EMC code. EMC will handle rotary axis, 6 dof machines, etc. Way beyond me though. EMC is actually written by NIST, so it's your tax dollars, but it's free to you and to american industry. 
Feel free to contact me off list for any other details.
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Any of you who are interested, just give me a holler. I can take lots of pictures, give you wiring diagrams, and walk you through building your own. After doing it once, and realizing how it is done, it's not to bad at all. Trivial compared to figuring out which hydraulics I need to add to my new tractor.
Seriously, I find that there is a middle ground in doing the CNC retrofits. There are people who buy turn-key packages (mill, electronics, software, CAD) and then there are people who are interested in building every part from scratch. I started out the scratch route, and realized that while I enjoyed building circuits, soldering, etc, I was really wanting to start making metal chips. I ended up floating in between - Buying motor drives, soldering my own cables and connectors, and installing the EMC software myself. When I did it, EMC was kinda a tough install, but now, download or mail order the BDI disk, put it in the CD rom, let it boot and install, and you are done.
I'm starting my big construction project right now, but in 7-9 months, I'll be re-assembling my mini mill in my new shop I'll photograph everything and post it up to follow.
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