This is probably the cheapest materials that can be used to make a cnc router table, The idea came from a guy on the net who sells plans for cheap homebuilt machines. but I was able to build based on the pictures on his web site (Thanks JCK...Ha :-) and my 15 years as a Machinist and CNC programmer , BTW this particular design machine he gave up on although not sure why, but I will see if I can make it work. The design uses black gas pipe as the linear rails and roller blade bearings ride on the pipe. told ya it was cheap -) The structure is MDF, I guess you would say it is a cousin of particle board but it is very straight and flat and cheap. I  used aluminum angle and 1/4 20 bolts at all the joints for extra rigidity. The ends of the pipe ar supported in adjustment blocks, works sort of like a 4 jaw chuck although some people would claim they invented this design (JCK). I'm glad somebody did it makes alignment of the machine a breeze. This was built mostly all from materials found in Home Depot except for acme screws although you could use all thread rod I choose a 3/8 8TPI acme rod because the courser thread gives a little more speed. Oh and my adjustment blocks are shaft collars that I drilled and tapped to support the gas pipe. both of these items where ordered from MSC along with limit switches which I still have not mounted and wired. Having to much fun cutting stuff hehe. The cutting envelope on this machine is 24"Y x 36"X x5"Z It uses 150 oz/in nema 34 steppers and a hobby cnc controller. See my controoler page for details

   This is the Y and Z axis not mounted yet.                                     

This is the X axis gantry. 

Closeup of z axis

Mounting the y,z axis to gantry

Another view

Completed router table cutting a door sign, this was the first big part I cut I have since gotten a shop vac and extended the hose down next to the tool for dust collection as you can see it gets everywhere  

The router is craftsmans version of a rotozip it had the same specs as rotozip but about 1/3 the cost and I got a replacement warranty for $9 I just know I can wear it out or crash it in under 2 years :-)