The nozzle path and speed generated by Simplify3D is already very good
but it could be better
regarding:
- the very start,
- the bottom ooze shield layers, and
- lonely support structures.
The 1st thing that should be improved is the
path immediately after the nozzle filling pre-extrusion at the front right corner of the build plate. It's well designed in that it deposits a blob at the edge of the build plate to ensure regular flow of material (
step 1 and 2 in green below). It's badly designed in that in
step 3 (red), it drags both nozzles
through the starting blob which often leads to material being stuck to the outside of nozzle. This material then smudges the print esp. for the unused nozzle in a dual print (see next photo, top left). The path should be corrected to avoid the starting blob (3 improved in green) by going diagonally to the center of the build plate instead of first left through the blob then up (3 bad in red),
- Problem 1: nozzles scraped through starting blob causing smudging along the path and later in the print.
The next thing that should be improved are the
first ooze shield layers (yellow arrow below). They are deposited too rapidly, often don't stick, and are then dragged causing linear stretches instead of the curved paths defined in the print code. They should be deposited more slowly and earlier in the print process. In this case, the first layer was deposited after the raft and 2 layers of support in blue. By the time the inactive white nozzle had emptied, counteracting the pre-extrusion. The first ooze shield layer should have been put down in blue and before the support structures are printed on the raft. This would have led to better attachment and less smudging.
The
smudging of the print heads (red, top left) because of crashing through the starting blob is apparent in the drag marks at the top left. A better initial head path and an earlier ooze shield would reduce that.
The first time I printed this model was without a raft. This worked well except for
disconnected support structures (orange boxes) which were frequently knocked over later during print head travel causing bad structures above. Support structures should always be crosslinked (green) esp. when touching the build plate to give them more stability. This would have been easy for the isolated support in the orange boxes but the algorithm is not set up properly to take this into account.
- Problem 2/3/4: bad first ooze shield layers, drag marks from starting blob, and lonely fragile support structures.
Changing these points in the automatic path generation process would significantly improve prints.
- Theoretical print path
