Simplify3D Slicing Software

Hey all,

I was having some problems with some models producing wacky layer shifting gcode for the printer. After adjusting the stepper motor power through the full range and seeing no fix, I read about Simplify3D and thought I'd get it and provide a quick review.

It's $140 but it's amazing. Although the software doesn't have a built in GMAX profile, which honestly you need to reach out to them about Gordon, it was really easy to setup. I only spent a few minutes copying some settings from the Slicer profiles provided by gCreate to the "process" in the Simplify3D software. Within 10 minutes of installing it I had it printing the most amazing model so far. Its a prototype for something, otherwise I'd show it, but what Slicer was struggling with Simplify3D had zero issues with and it sliced in seconds.

The only stuff I had to research a little was setting the x offset for my dual extruder and that was accomplished by adding this gcode in the process settings script "Starting G-Code" tab:

M218 T0 X0 Y0
M218 T1 X44 Y0

This sets the offset between extruder 1 (T0) and extruder 2 (T1) to 44mm.

Then I also added this gcode to the "Ending G-Code" tab to move the extruder to home position after the print completed:

G28 X0 ; home X axis
G28 Y0 ; home Y axis

I used all of the predefined settings for the "Cartesian Robot" printer type for everything else and it was a piece of cake.

It slices, generates support material and provides a visual 3D toolpath visualization lightning fast. You can then see the toolpaths visualized for every layer and speed through time to see how it'll all be printed before exporting the gcode to disk or via USB to the printer.

The print bed UI is a great user experience as well. Easy to use with regular mouse clicks and the occasional use of Ctrl or Alt keys if you want to rotate or scale your models. There are several repair tools for fixing mesh issues. I haven't played with using multiple "processes" yet but being able to set different print settings for different layers of your model is pretty trick.

Anyway. It's awesome and IMO is worth the money if you can spare it.
I also needed to add this gcode to the scripts section "starting g-code" tab:

M204 S700 ; set default acceleration

I didn't see where to set this in the UI and without it the GMAX will try to fly off whatever it's sitting on. :) Without this gcode I had to turn the gmax operating speed down to 50% for it to print at a pace I would expect.


Staff member
We have purchased simplify3d and we are evaluating so keep tuned. As for the acceleration, we have uploaded new gMax 1.5 firmware which lowers the default acceleration to 1100 instead of 9000. Check out the download section.

For gMax 1.0 users just make sure to check the wiring diagram from the manual if you wish to use the new firmware. Some of the wiring designations have changed (for the hotend and extruder fan locations).

I just viewed the first slicer tutorial and it raised one question regarding the offset for the second extruder (@ 26:58 in the video) . My question is how is the offset calculated?

In your video you show the offset for the second extruder as x=43.65mm and y=-0.25mm. Grumble said he set his offset to x=44.00mm and y=0. (using different software)

So how is the exact offset measured? Is it done by trial and error? Do I just measure the distance between the print heads with calipers? If so, that seems easy for the x axis but what about y? Sorry if the answer is obvious - I want to be able to "hit the ground running" with assembly and tuning when it arrives later this week. This is the only thing that was unclear in the video.


@Gordon - Glad to hear you guys are going to check this software out. I love it. I feel I haven't set my acceleration properly though but it sure prints nicely at 700 but I feel there is room to open it up a bit. Sounds like I can go to 1100. Thanks!

@shaqFoo - For the offset for slicer or Simplify3D I did in fact measure the distance using a digital caliper. I stuck one end in the hole of extruder 1 and the other in extruder 2 and came up with 44mm. I didn't measure any offset in the Y direction because I assumed with how it was printed they'd be lined up. If it's not quite right some printing trial and error as you mention will help tune the settings.


Staff member
Hi Larry,

You can measure the offset with a pair of calipers but the best is to start with our values and do a few trial runs. While this offset can be set in the firmware it may vary slightly per printer due to a number of factors.

We just assembled a printer the other day and we used X:45, Y:0.05 for it.

Once you start with those settings, go into slic3r and set Extruder #1 to the perimeter and set Extruder #2 to the infill then slice a simple model (like a cube).

Of the offsets are wrong you should see that the infill will overlap one side then you can adjust the values accordingly.