Hi
I´m on the start to build my own router. I will build it in MDF board and are going to use motors like this

Astrosyn 23LM-C303-09 3,5 V/Ph 1,4 A/Ph

How big tabel can I build?
I would like to be able to rout workpieces that are about 1 meter x 1,5 meter.
Is this possible
How large motors do you need?

I think the sizing of the motors has more to do with resistive forces acting against the motor ie: friction, inertia (weight of gantry, leadscrew, etc.) and needed cutting force. The size of the machine is only limited by your needs. Also the size of the motor may determine the max speeds of the machine.

That is a pretty large machine. I would stick to 12x24" max unless you have big money for a drive system. Those steppers may move the machine around, but not too quickly.

What you learn on a small machine will make a larger machine posible. It is also very hard to make a machine that size rigid enough out of MDF.

Eric