[medu2015]

I have just completed the first cut of a new machine design. The base apron and head are to be epoxy granite and the vertical would be a 6 x 12 filled with epoxy granite. The cylinder on the back would provide force to offset the weight of the head. All of the rails would be 25mm and the ball screws 20m. As it is now the travel would be X 18" Y 12" and Z 24". The design also calls for a 16 position tool changer. I would appreciate comments and or suggestions.

[Eldon_Joh]

I would make the distance between the Z axis rails to be equal to the distance from the spindle to the rail. this way the slop in the bearings is not multiplied.

you might want a 12 inch by 12 inch column, you can put an 8 by 8 beam in the middle of it and fill only the gap between with EG, saves weight.

you can cut and then weld the column back together, to taper it, again to save weight and EG fill, while preserving stiffness.

[medu2015]

Eldon_Joh
Thank you for your suggestions. I will add them to the list of possible changes to the design. There will be some time before the design is frozen as I will prototype the tool changer first.