Need help with PVA printing

[DRIPrinter 0]

Hello!

I've just started trying to print with PVA, at first supports on some PLA prints but seeing as that didn't work, I've been trying to print some PVA-only small test prints to see if I could solve my problem. For the two prints in the photo, I used Cura recommended settings, and I? was hoping for some expert advice on what is wrong and what settings I should use.

Thank you!!

 

[fbrc8-erin 267]

How long has your PVA been open? How has it been stored?

 

Does it feel flexible?

What nozzle size are you printing with?

Layer height?

[DRIPrinter 0]

It's been open for about a month, ever since my workplace first got the printer, I think (not 100% sure, but definitely for about a week. It hasn't really been stored in any special way, and I know that at least for the past few days it's simply been sitting at the printer. Is the problem that it's absorbed too much moisture? I've attached a photo of the spool, as I have read that color can be an indicator of this.

The prints feel very flexible and the material itself feels pretty flexible, in that it's much less rigid than materials such as PLA and ABS but it can't be stretched back and forth like some kind of rubber (although the print can). 

I'm printing with a BB 0.4 extruder. I've read that this was what is compatible with PVA.

I've used 0.2 layer height (on Cura).

Thank you very much for your time!

  

[fbrc8-erin 267]

If it feels flexible--like you could tie a knot in it, or scrunch it up like a piece of paper--it probably has absorbed too much moisture. When it's fresh out of the package, bending it feels pretty similar to bending PLA or ABS. 

You can try baking it on the heated bed for a few hours at 50 or 60 C to see if it helps try it out--put the whole roll on there.

 

When not printing with it, I recommend putting it in an air tight back or plastic tub with silica packs to absorb the moisture. It's not going to go back overnight or anything, but the more moisture that's in the air, the more is going to find its way into the filament if it's exposed.

 

BB .4 is perfect; I see a lot of questions sometimes about whether PVA can be used with the AA Core, so I always like to check.

[DRIPrinter 0]

Thank you very much, I'll try that!

When you say baking it, do you mean the whole spool on the printer's build plate?

 

[kmanstudios 1,120]

26 minutes ago, DRIPrinter said:

When you say baking it, do you mean the whole spool on the printer's build plate?

Yeppers :) Best heating control you can get. Just cover the opening to keep the heat in and fully around the material. It will still get out the top, but it will not flood out the front opening.

[Brulti 177]

It is strongly advised to always keep PVA in a box or bag with some kind of desiccant in it like this: https://www.youmagine.com/designs/drybox-for-pva-ultimaker3