Student looking for Circuit board routing CNC

[Bonz099]

Hey guys long time fan of this site first time post. Im looking to build a small to medium size CNC machine that is capable of milling PC boards. This will more than likely be the only function required from the machine. I looked at a few machines especially the Mantis 9.1 (http://makeyourbot.org/mantis9-1) but the working area appears to be tiny.

So I have 2 issues im running into, it seems as though all the plans for a machine require CNC machined parts, if not from parts that make up the machine, the plans for the stepper controller boards can only be made.

Does anyone here have the ability to mill a set of boards using an open source layout so I can get the electronics portion running? I know I can buy controllers but im a student so naturally im strapped for cash. So building is the best option for me.

The second question is, what plans would you guys suggest for something with a decent working area that is easy to build, has enough precision for milling boards, and is cheap.



Thank you again guys for your time,

[mcphill]

It's not DIY, but the price is right, the workspace is decent, and it can does pretty well with PCBs:

http://www.probotix.com/FireBall_v90_cnc_router_kit/

[Bonz099]

Thought this would be perfect if it was a bit cheaper.

http://cgi.ebay.com/Zen-Toolworks-CN...item2a0a4d9dd7

[Drools]

I have a larger router that I originally wanted to do just PCBs with but I'm going to make a smaller one 12x12.
I posted a zip file containing a dxf in this thread. The dxf is of the MDF router I intend on making.
laminating MDF
I scanned eBay for all the THK rails and I was able to get them for a good price.
Have a look at avrstmd.com for DIY drivers and the opensource section of the zone.
One note, I do not think you will get/make a router that will do PCBs for cheap.

[vger]

Bonz,

If you can locate a computer recycler in your area that is friendly to selling/giving a few scrap parts, you may be able to get some of the stuff you will need for fairly cheap/nothing. Older large dot matrix printers used steppers for platten movement and head movement. Some used small servo motors for head movement. The bar that the head moved on in some of them was fairly substantial and used bronze bushings on bars. The circuit board from the printer obvously has the drivers for the motors and with some inventive (cut traces and soldered leads) can be used to run the motors.

If you can find a few suitable printers that are identical you may be able to build something up with very little machine work needed. Use a pair of print head mounts and a pair of the associated bars for each axis. If you find some wide carriage printers you may be able to do a 12" by 12" table. If you come across some engineering plotters, then the area can get quite a bit bigger.

Steve

[RomanLini]

If you search spewtube there are quite a few cheap pcb routers, because the forces are very small from the tiny cutting tip and it doesn't need to move too fast (or be very large) they can be made from hardware store junk and still work quite well.

Most i have seen just use 1/4" threaded rod and old printer stepper motors, and homemade stepper drivers or even the stepper driver chips that came out of the printer (google for the chip datasheets).

Here's a couple of very low cost pcb machine examples;