where to start?

[Jonathan]

is this what you had in mind jon http://www.youtube.com/watch?v=iaRc8c4Qwn4 for a grand i,d like to see it done.

Nah, can do better than that. Give me a grand and I'll prove it :lol: You and JohnS reckon I'll be a millionaire 'soon enough' so I'm sure you'd get the money back!

The critical point is '18mm mdf ... nothing more than that', so the machine does not need to be massively rigid and a 50mm Z-axis should be fine. If you're sticking to that budget then start with a simple 8x4 rectangular steel frame mounted on a strong table or the floor which shouldn't cost much. Use linear bearings from ebay (linearmotionbearings2008), or to get it cheaper explore one of the other methods.

No mention of required feedrate, so I'm sure 3nm motors would be plenty... I reckon it's possible though in my opinion you'd be much better off in the long run spending more to start with.

Because as I found out it's more than likely wrong,to small or to weak
don't cut corners on the frame and ask ask ask away

By all means cut corners, as long as they're square. :naughty: Not going to be much of a frame without corners. Mine was far too big and too weak to start with.

[trounce]

Thanks Guys, been doing more research up until the small hours and starting to get a better undertsanding.
Whats the general rule for frame size vs the actual cutting area? I'm limited for space so I'm hoping that 10' x 5.5 will be enough for 8' x 4. I only ask because I was looking at the linear bearings on ebay and the nearest size I'll be needing are 2750mm which is a fair bit past the actual cutting size.