Converting STL to GCODE .....

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Converting STL to GCODE .....

Postby willsot » Sat Jan 06, 2018 7:59 am

Hi, I am totally new to FreeCAD and 3D Printing, bought a Trendy kit and have put it together and printed the test pillar (yeah), but when I download (STL) files from, my printer does not recognise or print. After doing some more research and have a bit of a play with several online/free programs I still can not figure out how to convert STL files to GCOPE for printing.

To comply with the rules:
Just downloaded FreeCAD so it should be up to date
FreeCAD version info
OS: Mac OS X
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.16.6712 (Git)
Build type: Release
Branch: releases/FreeCAD-0-16
Hash: da2d364457257a7a8c6fb2137cea12c45becd71a
Python version: 2.7.11
Qt version: 4.8.7
Coin version: 4.0.0a
OCC version: 6.8.0.oce-0.17
SORRY - The system tells me the STL files are to large to attach, but they are from (

The problem:
Open the Filter or Dish STL file and select the object.
I have tried FILE-EXPORT select gcode as my file type nothing happens. No error, no file.
I went online and found several sites that explain a MESH analyse process, followed by a PART building process, then export as GCODE, but again no error, no file.

is there a simple way (using FreeCAD) to convert STL files to GCODE for printing??

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Re: Converting STL to GCODE .....

Postby chrisb » Sat Jan 06, 2018 2:19 pm

The FreeCAD gcode won't help you for 3D printing, it is designed for milling. So it takes material off rather than adding it. What you need is a slicer program like Cura. That can read STL and output printer gcode.
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Re: Converting STL to GCODE .....

Postby MostlyHarmless » Sat Jan 06, 2018 5:54 pm

I have had good experiences with Cura, both on Linux and Windows. Still using the older 2.7 version as it has features I like that are nowhere to be found in version 3. I also played with Slic3r, but could not get it working properly.

Whatever slicer software you use you need to first configure it for your printer. That means it should know the actual GCode dialect, the dimensions of your printable volume, if the printer has a heated bed and such. If there isn't a preset for your exact printer Cura allows to write custom GCode snippets that will be included at the beginning and end of the actual print. Such GCode snippets are meant to put the extruder at a nice starting position before the print and put it into a safe parking position with all heating and stepper motors off at the end.

You said you printed a test tower. I presume that means that your printer came with some software and data (like my Anet A8 did in form of a micro SD card). You may find the necessary slicer profile(s) on that card/disk.
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Re: Converting STL to GCODE .....

Postby willsot » Mon Jan 08, 2018 1:57 am

Thanks guys!! I did kinda come around to the understanding that I needed a separate slicer program and started looking at both of the ones you suggest.

Have a great day!