3D Printing has come a long way since the first days of additive manufacturing. So much so that alternative materials are the norm however they are so difficult to print with. One such material is Flexible filament. The brand that I have been experimenting with is called GP3D and is readily available at Fry’s Electronics, which in and of itself is a great convenience and one I plan on taking full advantage of.

However there are a lot of articles out there warning of the difficulties of printing with this troublesome filament. Some of those difficulties include:

• Inconsistent prints
• Stringy prints
• Pimple prints and other surface defects
• and most pressing, Poor Print Bed Adhesion.

Some of these issues can be taken care of with slower print speeds, increased extruder retraction to minimize ooze, better slicers to reduce point to point string connections. I have printed a whole spool of this material so far and the only solution that helped me to increase print bed adhesion, I haven’t seen on the net so far.

That solution is to dual print your raft. What I mean by this is printing with a material that has great bed adhesion, PLA, then switching to your flex filament. To be more exact, my process was this:

Printing on a Makerbot Replicator 5th Gen, Smart Extruder, Out of the box print settings: (Temp: 215, 200 microns, Standard print settings).

• Begin the print with the PLA of your choice, (Natural “Color” is more inexpensive usually)
• Before the last layer of the raft begins to print, switch to the flexible filament
  • The standard settings for the raft use one base layer, two intermediate layers, and two finishing layers
  • Using the last layer for the switch allows for proper raft to model adhesion while providing the superior bed adhesion with the PLA
• Let your print finish as normal

This method allowed for great bed adhesion throughout the entire print. Before trying this, I used the flexible filament for the entire process and saw the print lift from the bed mid-way through. This warping on the base layers, similar to other materials with the same lifting problems (Like ABS), would affect the rest of the print by pushing the print in the later paths of the extruder head. This causes a few issues, the extruder head to digs into the print, little to no material is laid down, and frequent filament jams. If you experience this, it is always better to cut your losses and save your material rather than try to rescue or force the rest of the print. You will not be happy with the results. But I digress, the process outlined above allowed me to successfully print a pair of Sandals for my Fiancee (A thingiverse.com model remix I made).

An Example of a flex Filament Jam