PVA settings on dual extruder

Hi,

Attached a PLA / PVA print: I usually only print the support interface with PVA and let the main support be done via cheap PLA.

...but how to get rid of those tiny debrits of PVA oozzing out of the nozzle? more retract?

I guess the stings you can see in the picture is only because I changed another setting of my PLA the wring way

And here a closer look!

I usually do get a PERFECT print surface (PLA) when printing without support - but this PVA oozzing leads to tiny small holes after the PVA is dissolved.

( As already mentioned above: I just print the support interface with PVA - the support between is PLA which is easy removable without any residues.)

I was at the 3d printer world expo and saw airwolf 3d print with abs and pla supports. They then dissolved the pla in a sink cleaner and the result was great. I would look into this. Go to airwolf 3d's website

Yeah, I would say try more retract. Could you maybe print the PVA a little cooler too, or will that not extrude? Less temp = less oozing, but print too cold and it doesn't extrude anymore. I was printing PLA too hot once by a mistake and it had way more oozing. The PVA is only for support, so you can try out to your liking of course

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http://www.marinusdebeer.nl/

Quote
mrchris97
They then dissolved the pla in a sink cleaner and the result was great. I would look into this. Go to airwolf 3d's website

I already have 4kg of NaOH at home + a heatable ultrasonic cleaner: tried to dissolve PLA but not every PLA dissolves easily.
The problem so far is that I don't have a heatbed on my dual head printer that's why I can't print ABS + PLA at the same time (ABS not sticking on cold printbed...)
But thanks for your suggestion!
I also have HIPS at home plus 4 liters of Limonene: For testing ABS + HIPS as a support (HIPS dissolves in Limonene but one liter of Limonene costs about 20 Euro)

Quote
Ohmarinus
Yeah, I would say try more retract. Could you maybe print the PVA a little cooler too, or will that not extrude? Less temp = less oozing, but print too cold and it doesn't extrude anymore. I was printing PLA too hot once by a mistake and it had way more oozing. The PVA is only for support, so you can try out to your liking of course

How much retract do you suggest? 10mm to get out of the hot zone?
It will definitely work at 175 °C too as I have tested it but 190 felt "safer" to not clogg the nozzle in multi-hour prints

Edited 5 time(s). Last edit at 02/01/2015 11:22AM by RepRapper_Austria.