Im just starting the process of building (design stage) a 5 Axis CNC router. I already have a Y axis from a machine that had been torn apart.
As seen here. https://youtu.be/BdTr0OTAqx4
This was a quick and dirty way to flatten some large slabs. My plans are a steel frame/bed with linear rails for X axis. Use the existing gantry for the Y access and build a Z axis.
The first part I am designing is the 4th and 5th Axis for spindle. I am still looking for/finding a spindle with a taper tool changer (BT30 or something similar).
Here is what I have so far, I am open to critique on this design. All of the purchased components (bearings, flanges, etc) come from Mcmaster. The opening in the lower arm is so I can see the belt and my plan is to fill that with some acrylic or the like. Also the end of the arm I plan to cover with sheet metal to keep the mech inside clean. Everything else will be 1/2" or 3/8" aluminum.
I have a few Noob questions...
1, the stepper motor drives for A and B, do the steppers hold position when the machine is running (I assume so but I dont understand this). So it will hold the spindle at the B axis while X and Y are moving for instance.
2, In regard to the gantry, the gantry that I have is is an 1 1/8" thick by 7" tall piece of Aluminum. Is this substantial enough for a Z axis that will be ~ 28" (16 inches of travel plus 12 inches for the 4/5 axis head) inches from the gantry when fully down? Im thinking I might need to add to this to make more like a C channel possibly. Im not so much worried about flex in the vertical direction more so twist of the rail because of the long moment arm. Thoughts on this are greatly appreciated.
3, I am planning to add 0 position prox switch to A and B axis, however should there be positive physical stops on the max limits? Also how far should they go? I was thinking 360 deg on A and maybe 200 on B (100 in each direction)?
I will keep adding pictures as I draw more of the system any help is greatly appreciated!
Thanks
Scott