"3D Pen" Filament

[CrazyIvan]

On the suggestion of a friend, I bought a selection pack of filament advertised for 3D pens from one of the usual market places. 10m each of 1.75mm PLA in 22 colours – potentially a great way of stocking multiple colours without too much outlay. When they arrived, I weight a sample coil as 31g, so that's as expected for a 10m length.

What could go wrong?!!

Well, it did. I grabbed a frog model from Thingiverse (I have a friend into frogs), sliced it and went to print (9g filament - that's about 3m). The raft went down OK, so I went away to come back later... and wished I had watched it some more first.



(terminated early, but not long before completion)

I don't have enough experience to know whether the same would have happened had I bought a reel of green PLA, It appears the right front foot lost adhesion with the raft, so that after that the right front leg was bing printed in free air.

Everything else looks pretty good (there is a discontinuity on the left front leg, but that might be a knock-on effect).

I'm re-running the print now, and this time it looks to be printing without the previous defect.

[CrazyIvan]

Yep, pleased with that (after a little finishing).

Credits

"Treefrog" by MorenaP https://www.thingiverse.com/thing:18479

Licensed under the Creative Commons - Attribution - Non-Commercial - No Derivatives license.

[3dadmin]

Looks great !

[CrazyIvan]

I then tried another and it was a miserable failure, the leg came off again. I think these pigmented filaments might need different settings for support Z spacing in the slicer.

This leads to a startling conclusion: 10m of filament, which should be enough for three frogs, is barely adequate. Yes, OK, you can use your bulk filament to test the model, but that doesn't help tune the slicer for the production filament.

What's needed is a calibration print which doesn't need too much filament and can be used to refine the slicer settings and save them for that particular filament. These might even be affected by room temperature.

[Antipodean]

I then tried another and it was a miserable failure, the leg came off again. I think these pigmented filaments might need different settings for support Z spacing in the slicer.

This leads to a startling conclusion: 10m of filament, which should be enough for three frogs, is barely adequate. Yes, OK, you can use your bulk filament to test the model, but that doesn't help tune the slicer for the production filament.

What's needed is a calibration print which doesn't need too much filament and can be used to refine the slicer settings and save them for that particular filament. These might even be affected by room temperature.

I wonder if this is caused by moisture in the filament? a spot of moisture reaching the nozzle could cause an "explosion" with the temperature of the nozzle suddenly superheating the water.

[CrazyIvan]

I wonder if this is caused by moisture in the filament? a spot of moisture reaching the nozzle could cause an "explosion" with the temperature of the nozzle suddenly superheating the water.

I don't think so. The print let go at the interface between the raft and the model, which would be rather a coincidence if it were some random event. The adhesion between raft and model is not as good as with the other filaments I'be used (black and white), which is good for clean-up but not good for probability of a successful print.

I got lucky, but with more filament to spare I would try fine-tuning the slicer parameters.

[Antipodean]

I wonder if this is caused by moisture in the filament? a spot of moisture reaching the nozzle could cause an "explosion" with the temperature of the nozzle suddenly superheating the water.

I don't think so. The print let go at the interface between the raft and the model, which would be rather a coincidence if it were some random event. The adhesion between raft and model is not as good as with the other filaments I'be used (black and white), which is good for clean-up but not good for probability of a successful print.

I got lucky, but with more filament to spare I would try fine-tuning the slicer parameters.

So now we need a metal box with an extrusion port of suitable size to recycle the filament from the failures...

[CrazyIvan]

So now we need a metal box with an extrusion port of suitable size to recycle the filament from the failures...

There are kits available, but they're rather expensive.

[CrazyIvan]

I wonder if this is caused by moisture in the filament? a spot of moisture reaching the nozzle could cause an "explosion" with the temperature of the nozzle suddenly superheating the water.

PLA filament is much less susceptible to moisture absorption [than ABS, PETG...].