Newbie and Wooden Machines

I am new to the world of home CNC machines although I worked for a number of years in the electronics industry supplying equipment for CNC machines so am not completely green.

I am interested in building a CNC milling/routing machine and am comfortable with the stepper motor drive and software issues. Not being a very strong mechanical engineer I am challenged by the design of a suitable milling machine. I would like to build a three axis machine capable of machining soft materials (wood, plastic etc) up to say 500mm x 300mm x 100mm. There seem to be two options - buy a manual machine and convert to CNC or fabricate a machine from MDF or similar timber material. Having only limited workshop facilities the idea of building something out of MDF appeals, but is it practical and does it provide a workable machine ? What type of slideways should I use, what type of lead screws can I use - the idea of using ball raced double extension drawer runners and threaded rods appeals but again is that workable ?.

Do you know of any suitable designs or have you built such a machine and can you give me any hints and tips or pitfalls to avoid ?

Regards Peter Seddon
Birmingham, England



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