[PVA too dry? Brittle and cracks in feeder]

Thank you for all the inputs.  

 

I do have it on the desk right now outside the desiccant box.  It's pretty dry here (Denver) in general, shop humidity bounces between 20-30% (but currently blizzarding with 92% humidity outside...)  I will put it back into it's own desiccant box in a couple days and monitor humidity level over time.  Aiming to level out at 20%.  Will report back with results.

 

As for: 

13 hours ago, gr5 said:

Is it only the outer meter of filament that cracks easily?  Or if you throw away the outer meter of filament is it okay after that?

No, the whole spool is super brittle.  

 

And it is not possible it has seen UV degradation, it is in a windowless workshop.

[PVA too dry? Brittle and cracks in feeder]

I store PVA in sealed box with the "under sink" dehimidifier that gets recharged by pluggin into wall: https://www.amazon.com/Improved-Eva-dry-333-Renewable-Dehumidifier/dp/B000H0XFCS/  These things I think are power dehumidifiers.

 

I monitor humidity with two battery powered gauges, humidity stays at a constant 10%.

 

I went 3 months between PVA runs, spool was maybe 6 months old total by this time.  The filament was so dry and hard that it cracked in the feeder on our S5.  

 

When I managed to get the filament all the way to the extruder without cracking, it would extruded extremely unevenly and almost in a pulsing pattern.

 

I put in a new bag of Ultimaker PVA, and it extrudes perfectly.   

 

So, can PVA be too dry and does it have a shelf life?  Others experience here?

[PVA not sticking on glass]

Your initial PVA layer is too far off the bed.  I've caught Cura doing this a few times, I think it is a bug.  "initial layer height" would get kicked to .27mm (when printing .1mm layer height), which would result in the bead of PVA not being squished into the glass.  I change that "initial layer height" to something around 1.5x my layer height.