Hi,
I am a big fun of mach3. I decided to use mach3 for my homemade 3d printer like reprap or makerbot. I use an arduino for the extruder temperature control. A host software is messaging over usb (serial rs232). mach3 is controlling the 4D system via gcode. I have a problem. The serial communication has a negative effect on mach3.
the motors did not work smooth when I plug the usb.

Please send me your advice to correct this issue.

Regards,
Nuri Erginer

Mach needs most of your computer resource to provide the correct timing etc.
Just a thought, but...... Using an external timing device such as the "Smooth Stepper" may free-up sufficient Mach resource to allow your RS232 communication.

Tweakie.

Definitely post what you find! I am interested in making and installing a Rep Rap head on my Sherline/A2ZCNC mill.

I rewrite the arduino firmware. It will not cominicate with pc. It is now standalone temperature control system. Mach3 can run smoothly now. I will let you know about the progress.

regards,
Nuri Erginer

What are you using to create the G-Code?

I am using skeinforge (http://fabmetheus.crsndoo.com/)
it gets 3d stl file as input and produce g-code. it has lots of parameters for fine tuning.

regards,
Nuri Erginer

There has been another discussion of this , what you might want to consider is using the spindle speed as the extruder control. Would give you a way to start and stop the extrusion, as well as control the extrusion rate. Might require that you do some translation of output codes, but that should be a faily straight-forward text substitution which could be done using find/replace all, or by writing a small program in basic/C/other language of choice.

what I am trying to do is easy switching from a cnc to 3d printer. Mach3 will be the software. You will plug a extrusion head instead of a spindle and you will begin to print. A arduino based circuit board will control all the stuff like extrusion temperature, extrusion speed and build platform heating. I prefer to separate the 3d printer requirements from mach3 software. This will not disturb the mach3 to run the cnc code and will help people to switch between cnc and 3d printer.

regards,
Nuri Erginer

what I am trying to do is easy switching from a cnc to 3d printer. Mach3 will be the software. You will plug a extrusion head instead of a spindle and you will begin to print. A arduino based circuit board will control all the stuff like extrusion temperature, extrusion speed and build platform heating. I prefer to separate the 3d printer requirements from mach3 software. This will not disturb the mach3 to run the cnc code and will help people to switch between cnc and 3d printer.

This is a brilliant concept Nuri - I am following this with great interest.

Tweakie.

Thanks Tweakie!

Let me tell you what I did up to know. After then I will share all the information.

As you know there are two approaches to the extrusion motors in 3d printing community. One is 5D concept that use a stepper motor as a filament feeder. The other is a gear head dc motor.  For the first one I slightly modify the skeinforge software for 'E' letter. For the forth dimension skeinforge use the letter 'E' as an axis definition (like X,Y and Z) After the small modification software produce gcode with letter 'A' instead of 'E'. This is suitable for mach3 to read the code and control the stepper extrusion motor in desired speed. The arduino based circuit is only dealing with extruder temperature, build platform heating and cooling fun control. This works fine. Feed rate, extrusion speed and temperature are the main parameters that you have to fine tune for better print quality.

The second concept is a gear head dc motor. I use the spindle relay for on-off control of the dc motor. I just write two M-code macro to define the M101 (start extrusion motor) and M103 (stop extrusion motor). This time arduino circuit deal with PWM motor speed control with a potentiometer.  

I will soon share the information so that you can build a kit by yourself (or buy one) and screw it to your mach3 cnc and start using it as a 3D printer.