#replicatorg

Having printed the same object sliced with Makerbot Desktop and Skeinforge and using hairspray or glue stick on masking tape, one of the combinations was clearly winning.

Hairspray + modified Skeinforge raft. 

The hairspray kept the first layer better adhered to the tape, and the Skeinforge raft code just worked better, partly because the Makerbot code printed too fast, and that my homemade code created a significantly larger raft at a slower speed.

I might want to use part of the Makerbot starting code that draws a line along the perimeter of the build plate to clear any old filament. The Skeinforge approach is to extrude a blob for two seconds, which almost always gets stuck in the print. So I have removed that line - it is "G4 P2000".

One of the reasons for changing to Cura for slicing is that the Brim feature is integrated. Luckily some clever people have made a mod for Skeinforge that allows this as well. I found a file called skirt_with_brim.py somewhere online, searched for the file skirt.py on my computer, renamed the old version skirt_backup.py and the new file to skirt.py.

Within the skeinforge settings in the slicing profiles there is now a possibility to set a brim width. 

"Activate skirt" needs to be checked, "Convex" can be unckecked, if you want the brim to follow the shape of the print. "Gap over perimeter width" I set to 0, since I wanted the brim to hug the base and meld together with it. "Layers To" is the height of the brim in layers. The "Brim Width" defines the width in lines, so this will change according to the filament size etc. Remember to disable rafts, or things will look strange.

Opening up the resulting file in Repetier Host clearly shows the brim - and a problem I read on the internet, that objects are completely off center. An stl/g-code centered in Replicator G will have its centrepoint on one of the cornes in Repetier Host.

I checked what happens with the width of the brim when using my standard settings for a Replicator2 by exporting g-code with and without a brim and checking the dimensions at http://gcode.ws/ - a handy website for previewing g-code.

15 layers of brim gave me 6,6mm extra width, which makes 0,22mm per layer added, since there are 15 layers on both sides of the model.

After fiddling around with Repetier Host and Cura for slicing, it occured to me that I had no idea if the settings in the configuration would work or not. So even though the slicing time was impressive, I went back to skeinforge on ReplicatorG, because I don't have a machine to do extensive testing on.

So to fix the slow slicing speed, I changed to a different Python interpreter, in this case PyPy. Since ReplicatorG uses Python 2.7, you need to make sure to get the right version from here.

Unpack the file somewhere handy, go to ReplicatorG settings and navigate to the PyPy.exe in the Python interpreter settings. Slicing should be 5-10 times faster now. Not sure how muchn I gained, but what used to take at least 45 minutes now takes about 5, so I'm happy!