Sunday, January 13, 2019

What's better... Skeinforge or CuraEngine?

This is a quick comparison of a deprecated slicer called Skeinforge and another slicer called Cura. Cura is a popular slicer and host that is currently updated.

My understanding is that the CuraEngine is based on a fork of Skeinforge. It's primary improvement is speed. Skeinforge has been the slowest slicer I have encountered, and I have tried just about all of them starting in 2011 when there were only about 3: Skeinforge, ReplicatorG and Sfact (which is just a dumbed down version of Skeinforge).


For this comparison test I'm using an object from Thingiverse called the Calibration Temple (thing:10199530). This has been my penultimate test for printers and profiles. Primarily because of the delicate size of the columns and the object's bridging requirements. It's 38mm tall.



I configured Cura as closely as I could to the Skeinforge Durbie-Normal profile. This is my best general all purpose profile. Slicing speed for Cura unsurprisingly won. It came in at about 4s. Skeinforge came in at about 16s. A considerable time difference.


Even though both slicers are set at 32mm/s, the print speeds are off by 2:11 with Cura printing at 29:28 and Skeinforge at 31:39.



Above are the results. The object on the left is sliced by Skeinforge. The object on the right is sliced by the Cura. Both are printed with PLA.

Skeinforge wins by far for best quality. It's hard to see, but the bridging with Cura is a messy tangle under the dome. The Skeinforge sliced object has a clear inner dome and the columns are straight and clean. There is but one off strand from bridging.

Why? Skeinforge took more time to print. The extra 2 1/2 min for printing was caused by a setting in the cooling profile.


Skeinforge allows for either a slowdown or an orbit when printing delicate areas that may be damaged by excessive heat in the printed parts. If the previously printed area hasn't had time to cool and solidify, the successive layers will began to distort.

In this case, the slowdown also helped by physically slowing the printer down and thus printing with greater care the delicate columns. This added time to the print job, but also greatly improved the finished product.

Skeinforge also has many more controls for dealing with bridging and other printing challenges. This is what makes this slicer still viable today.