Using Slic3r with the FlashForge Creator Family of 3D Printers

• Slic3r's default g-code wasn't setting temperatures properly for my machine. This g-code uses the proper M-commands for the FlashForge and utilizes the Slic3r variables to fill in the temperatures you have set for the first layer.
• Note the use of the "" variable. I couldn't find this documented or addressed anywhere, but I tried something and got lucky. The variable seen in all the documentation and the Slic3r .ini files is "", but on my dual extruder printer, that was returning two numbers separated by a comma. So the resulting g-code would be M104 S225, 225 T0 (which doesn't compute). On a whim, I decided to try "" and found that yes, this will return just the value for the first extruder (and "" is for the second extruder).
• The default Start g-code used a simple purge routine to extrude some plastic in a corner of the build plate before starting the job. I found that sometimes, especially if there was some oozing plastic already hanging on the extruder nozzle, the blob of plastic created by this initial purge routine would get caught on the nozzle and would then get dragged along, interfering with the first layer of the print. I greatly prefered Makerware's approach, which extrudes a thin line of plastic along the front edge of the build plate before starting a job. It has a tendency to wipe off any oozing plastic that was already on the nozzle so you get a nice clean start to each print. I analyzed some g-code from Makerware and incorporated the appropriate bits here, with some modifications (i.e. it uses Slic3r's "" variable.)

• Same use of temperature variables as discussed previously. Note the use of both "" and "" for the first and second extruders, respectively. These temperatures are determined by the material you're using, as defined in the Filament profiles within Slic3r.
• The same improved purge routine discussed above but modified so that it is repeated for each extruder. The second extruder uses a Y value that's +1, so it lays the filament down right next to the filament from the first extruder.
• Tool changes for dual extrusion prints weren't working for me. When I looked at Slic3r's g-code, I found that it was using "M108 T0" or "M108 T1" to change extruders. Looking at g-code from ReplicatorG/Skeinforge, I saw that the Makerbot type printers seem to be looking for a simple "T0" or "T1" and don't seem to recognize the M108 commands. Using the above "Tool-Change G-Code" takes care of this issue by inserting the appropriate commands before each tool change. The M108 commands are still in the g-code, but they just get ignored by the printer.

Converting from G-Code to .X3G Using GPX as a Slic3r Post-Processor

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