Problems with Quality (holes)

[ace16vitamine]

Dear all,

i finshed a long job (20h) with my jgaurora A5 (Marlin).

Sometimes I have blobs and holes, but I really have no Idea what is going on wrong.

To my settings

PLA: 215
Bed: 70
Retraction Distance: 12mm
Retraction Speed 4000
Nozzle Diameter: 0,4
Extrusion Multiplier: 0,93
Coasting: 0,4
Wipe Distance: 6

Thanks
Stefan

[billyd]

In my experience coasting causes alot of problems. You shouldn't need it with PLA

[ace16vitamine]

OK... Next Time I try to disable coasting.

Any Ideas regarding the blobs?

[horst.w]

Dear all,

i finshed a long job (20h) with my jgaurora A5 (Marlin).

Sometimes I have blobs and holes, but I really have no Idea what is going on wrong.

To my settings

PLA: 215
Bed: 70
Retraction Distance: 12mm
Retraction Speed 4000
Nozzle Diameter: 0,4
Extrusion Multiplier: 0,93
Coasting: 0,4
Wipe Distance: 6

Thanks
Stefan

OK... Next Time I try to disable coasting.

Any Ideas regarding the blobs?

I guess your printer has a bowden-printhead.
Therefore the retract is unusual long. With a value of 12 mm (so it is right) you are pulling back the tip of molten filament completely out of the melting zone of the heatbloc.
Nevertheless there are staying remains inside the heat chamber and when the restart distance is zero (not described in your listing) or positive the tip of matarial is feeded just down to the nozzles hole. This cause that all remains will be pressed out and build the blobs.
The effect will be enforced much with the retraction speed of 4000 (per minute? = 66 per sec.), 25 mm/s is more than enough.

I have set for my Mankati with 70 cm bowden the best of 5,50 mm and for ABS a restart distance of -0,13 mm (E3D V6-nozzle, 0,40 mm)

horst.w
GER