Hello, I am from France so as we are crazy froggy French, my english is not good.
Sorry ! ;)

I want to design and build a CNC mill for gridding aluminium to steel metals.
In this way, I am calculating the structural design for :
- Save money
- Build a good machine whith high accuracy

As I think rail and block whith caged ball or roller are the best system for having a good accuracy, I read with attention the mechanicals characteristics of the rails and blocks manufacturers .

The blocks have :
- Basic load rating : Dynamic and static in radial, reverse radial and Side
- Static permissible moment

As I know, the milling process apply to the cut tool some forces and some moments to the blocks.
So If I know these forces, I can calculate moments apply on the blocks.
Whith a correct security coefficient, I can chose the good rails and blocks for my CNC.

Right ?

So, does anyone know the formulas to calculate these forces factor of the material characteristics, the speed, the cutting tool ect...

Is it the good way to dimension my structure ?

Can you help me ?

Yours,

Michel

Hello Michel, and welcome aboard!

Yes, you are on the correct path. But of course if you make a bad design the rails will suffer.
As I use to say, you can buy the small linear rails - such as THK, Hiwin, INA etc - they will probably be overrated anyway.
I mill steel on Hiwin size 15-rails, no problem.

Regards,
Sven