PCL (Polycaprolactone) Material Profile

Motivation:

This is a material development project I started working on to develop reliable print parameters for PCL filament. PCL is unique in that it can be remoulded after heating in warm water (~ 60 [C]), and is a very tough and impact resistant plastic. I do not have any particular uses for this filament but thought it would be interesting to experiment with (I have been saving all my scraps to remelt for future projects).

The material I am using I bought from Filaments.ca: (link)

The goal is to embed as many print parameters in the “Filament” settings, I have found setting the material type to “FLEX” resulted in better prints than PLA/PETG base settings. 

WARNING: Special filament START/STOP Gcode is used to disable/enable “cold-extrusion” 

20210605: Findings so far

• Nozzle: 112-115 [C], Bed: 57 [C], Adhesion: PVA glue stick
• Cooling: ON, 60-100%, Slow speed: t < 40 [sec], Minimum speed: 10 [mm/s]
• Nozzle temperature needs to be greater than ~110 [C] for good flow response, but cooling needs to be well tuned for small features otherwise the material will not solidify.
• Prints tent to warp upwards at the edges, raising bed temperature and fresh PVA glue seem to reduce this.
• Very poor bridging performance… take care on top skin layer counts and cooling
• Next Steps: experiment with retraction for cleaner prints, further tune cooling for small feature definition (see Benchy improvements, left to right).

20240601: Revisiting

• Investigated alternative bed adhesion solutions, no good results thus far…
• Tried paper and balsa wood foundations, no better adhesion, best results have been achieved with glue sticks. 
• Currently floating the idea of using organic supports to suspend models above the plate, thereby minimising bed contact area → less material to warp and curl.