I thought I saw a geco drive for 3or4 axis. |
If you are refering to these drives,
www.geckdrive.com then no, you need one for each motor. yes 7 amps is good.
If you are building your first machine, I would stick to the cheaper xylotex board. It should be fine for those motors. You may want to doublecheck with them to be sure.
Also, start a little smaller for your first machine...say 2' x 2' or even less (I would recommend no larger than 2' x 1'). There are plenty of challenges in building a cnc router without the added complexity of a larger machine. Trust me...I know...
Eric