Im new, am a 3D designer. Need a New cnc machine and need advice and guidance

[gavztheouch]

It might be easier to use one large piece of box section for the gantry. Something like 150mm by 75mm, that way you have one nice flat surface after expoxy leveling to mount all your rails and ballscrews bearings. You also need a way of tensioning the motor and pully belt, slots in the mount would be fine. You might want your slots in the same axis as the center to center of the motor and pulley?

Another thing, you want to keep the pulley on the ballscrew as close to the bearing as possible.