PVA not sticking evenly to printing bed and on layers

[toilet-ovule-add 0]

Hi,

 

Does anyone have tips for better printing with PVA as support material?

The PVA seems to stick unevenly on my printing bed and on top of other layers.

Most of the times is goes well, but sometimes a complete loose web of PVA is floating through my printer when checking my print after a few hours.

Should i increase, decrease the flow (currently 105%) of PVA or disable retraction ? Something else to improve the printing of pva?

 

 

Cheers,

Peter

 

[kmanstudios 1,120]

Does it pop, smoke or sizzle when printing? If so, moisture is to blame.

 

What is it not sticking too? PLA?

 

As for sticking to the buildplate, how are you sticking your prints down?

[toilet-ovule-add 0]

No does not pop, smoke or sizzle. When feeding it drops down straight and does not curl. No dark spots in the PVA indicating that moisture is the issue.

Printer is in a closed environment with multiple moisture absorbing bags.

 

It does stick badly to PLA but as can seen on the photos worse on the bed itself.

So, sticks badly everywhere. 

 

Clean the build plate using ammonia and a drop of water. Rub it with cleaning paper till i feel some resistance.

Works perfect for all materials o use. Only now and then PVA gives me headaches. Because PVA does sometimes stops sticking on other PVA layers is do suspect the feeding or retraction settings...

[geert_2 558]

What if you wipe the glass with dilluted PVA first? So it has something to stick to?

 

You could recycle the old supports for this purpose.

 

[toilet-ovule-add 0]

Would be worth wile trying out if only the PVA would irregularly stick to the plate.

But it also sometimes does not stick to other PVA layers. Will try out to make a PVA raft the next attempt and see if 

i get a more stable PVA support structure then.

[toilet-ovule-add 0]

Although the PVA was dry and most of the time the  flow from the printhead seemed ok, it did some hot and cold pulls using PLA.

After some time there came small black parts came free. Ran it multiple times till it couldn't get anymore out. See if this helps.