One-click printing from Simplify3D to Octoprint

Created on Sunday, October 15, 2017.

Just stumbled upon this fantastic tip from user LumpyDVC. I reproduce it here in case that forum goes away, as forums are wont to do.

Hey All,

Found this nifty workaround on the Simplify3D forums for automating the sending of GCode directly to your Octoprint setup. No more saving the file and drag/dropping it around. Simply click “Save Toolpaths to Disk” in S3D as usual, pick your file name, and save. Your GCode file will appear in OctoPrint.

If you’re like me and not very savvy with Linux this is a perfect easy workaround rather than dealing with programs such as Samba.

You will need the following:

  • Simplify3D installed
  • Octoprint installed
  • cURL - Visit

Grab the Windows package that best matches your system. (eg. Win64 7.48 SSL SSH)

Extract and copy the following (2) files (located in Bin directory) to a directory in your Windows Path. (eg. C:\windows)


In Simplify3D go to:

  • Edit Process Settings -> Scripts

At the very bottom there is a box titled “Post Processing”

Add the following command line to the box titled “Addidional Terminal Commands for Post Processing”

curl -k -H "X-Api-Key: 1111111222222233333444455555" -F "select=false" -F "print=false" -F "file=@[output_filepath]" "https://octopi.local/api/files/local"

** You need to insert your specific API key into the command line. You can find it in OctoPrint ->Settings -> API **

You can sub the IP address of your Pi in place of octopi.local if you wish.

Anyhoo, Hope this helps anyone out there running Octoprint with S3D. Sure makes it more smooth of a process. I don’t take credit for this workaround just think it is very helpful..

LumpyDVC, Apr 5, 2016 Last edited: Apr 5, 2016

I put this code after all other post-processing instructions. I set select=TRUE but print=FALSE so that I can decide when I want to print my objects.

User centenary raises a valid security consideration with this method:

Note that if you use this approach, Simplify3D will embed your API key into gcode files underneath the “postProcessing” line. Anyone with public access to OctoPrint can then download the gcode files even without logging in, which will grant them access to the API key. This will then grant them full control of the OctoPrint instance.

If your OctoPrint instance is not publicly exposed, you should be okay. But if your OctoPrint instance is publicly exposed (i.e. to a network or the Internet), this is something you should be aware of.

That's all there is, there isn't any more.
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