A CNC 4th axis project. Inspired by a youtube video about building a hobbing attachment.
This project will have more complex electronics so it can also be used other ways. The project is intended to be used on a manual mill
with out any CNC capabilites. Signals from linear scales are used for some modes.
oxtools explaining helical milling and doing a similar project here
- Dividing head - move to a rotational position and hold.
- Helical milling attachment - maintain rotational position proportional to the position of a linear axis.
- Gear Hobbing attachment - syncronize the spindexer spindle RPM proportional to the main spindle RPM.
- Xilinx Spartan 7 FPGA
- ESP32-d0wd SOC
- TFT LCD MODULE
- Hall effect Sensor
- Spindexer
- a few encoders (models tbd)
- TTL linear glass scales already installed on the mill.
- A rotational quadrature encoder on the spindexer's spindle.
- a stepper motor (model whatever my makerspace has)
- a GeckoDrive stepper controller. (model tbd)
- Power supply
- Other electronic parts not selected yet
- Xilinx Vivado
- Arduino IDE (programming the sp32 included on the board).
- KiCAD
- Do we need a brake?
- What kind of transmission between the stepper and the spindexer
- Worm and wheel would be resistant to back-drive but may limit top speed.
- What kind of gear ratio would be useful (dividing heads use 40:1)
- What kind of top speed and holding torque do the stepper provide.