CNC millstrap help needed

I am adding 3D printing capabilities to my bench top 3 axis CNC mill and need some help on what route to take.

I've narrowed my choices down to 2 options, using the existing CNC controller or using the gen3 controller (which I have).

1) If I use the gen3 controller, the pin configuration for the stepper drivers is different than the current CNC, so there will be some modifications to make so they will be compatible.

2) If I use the CNC controller, I don't have to worry about hardware compatibility, and I can buy a 4th stepper motor driver to run the stepper motor on the extruder. I would however have to set up a separate temperature controller for the Extruder . I also don't know if the printer software will work with the CNC controller.

With either controller, I need to use my existing stepper drivers because my motors are too large for the gen3 drivers. Which of these problems is easier to deal with?

I helped a friend "repstrap" his little CNC mill a couple days ago so this is pretty fresh in my mind

Before we started, he had the machine in running condition using Mach3.

Basically we replaced the PC connected to the breakout board with a Gen3 reprap motherboard with 1 stepper driver.

Here is summary of what we did
-chopped the end off a parallel cable so the machine can be used as a printer or a mill with the swap of a cable.
-Used the printer cable to patch/connect the existing stepper signals for X,Y and Z(Enable, Step and Direction) to the reprap MB.
-Used the printer cable to patch/connect the minimum limits switches for X,Y and Z to the reprap MB
-The machine we converted had Gecko drives, so we disabled the charge pump
-Connected the 4th stepper to the MB.
-Using proto board wire up two MOSFETS that connect to the reprap motherboard(1 for the extruder and 1 for the bed)
-On the same proto board as above wire up your temperature sensors (1 for the extruder and 1 for the bed)

Instead of using protoboard you could use the Ultimachine RAMPS(any version) DIY kit to wire the MOSFETS and Temperature sensors. It will make things easy and cleaner for that bit of the job

My stepper drivers have pins for step, direction, +5vdc, and NC (and as many grounds), so information on how the two pin layouts differ would be nice. Also, can the limit switches be connected directly to the MB instead of the stepper drivers? If not, do the min/max wires on the cables connecting to the stepper drivers just receive +5vdc when the limit switch is pressed (or stop receiving voltage)?

... i've repstrapped my Isel-CNC-mill by replacing the original interface card by an ArduinoMega with an adapter card, that routes all the pins needed for controlling the steppers to the drivers in the CNC-controller.

The extruder has a separate temperature controller and the endstops aren't connected, as the software had some problems with the mechanical switches ... maybe i'll add the optos some time ...

Before this i started with a Gen3 (with separate extruder controller) and the host software, but with the ArduinoMega and printrun/sprinter it was much easier to start printing ...

---

Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

Hi

You are welcome to check out my site [www.cncdudez.co.uk] where I did the same thing and covered all steps.

As the guys have already said, you can simply make a breakout board that connects the 3D Printer controller board to your existing steppers.

Cheers

Sean.

---

******************************
[www.cncdudez.co.uk]
******************************