PVA blues

[aag 6]

I hate to admit that I have never been able to print any PVA with my Ultimaker S5. I have no problems with PLA and breakaway. But PVA, it always clogs the print core, immediately. I have tried BB0.4 and BB0.8, and both get clogged. I have cleaned the cores with cleaning filament until I got blue in the face. After cleaning, the PVA extrudes nicely for a meter or 2, and then it clogs again. It drives me crazy. What can I do???

[zungara 10]

how dry is your PVA? If it is not dry enough you will get problems. If it is nearly to dry it will easy break. I have no measure system but I start printing if it really easy break "into 1000 pieces" :-) But keep aware that it will not break in the tube.

Edited December 22, 2018 by zungara

[aag 6]

I kept it for 12 hours in a food dryer with warm air at 60°C, It's not really brittle, but on the test extrusion it does not make the cracking sounds typical of steam.

[Smithy 1,144]

Dry it again, PVA is a great material for support structures, bad really a mess when it comes to humidity. If you have more than 40-50% humidity and plan to print a longer job, you should consider to buy or build a drybox, to print directly out of this box. 

 

The filament makes not always a cracking sound like steam, it does when it is really wet, but you can get problems also before like a clogged nozzle and something like that. My previous print started ok after 5cm PVA stopped extruding for 3-4mm and then started again extruding and printing fine. Was also some kind of clogging but unclogged itself after some time.

[aag 6]

it seems to work now, for the first time ever. I am sure it is because of the bundled telepathic force of the community...

[Smithy 1,144]

1 minute ago, aag said:

I am sure it is because of the bundled telepathic force of the community...

I hope you haven't started a longer print, because I go to sleep soon and then the telepathic force could be weaker 🙂 

[Design94 4]

@aag

 

I had the same problems at the beginning with my UM 3 Extended. The humidity in my office during autumn, when you try to get some fresh air was killing my PVA. You should make yourself a storage box or buy the Polybox from Polymaker (no advertisement guys). This one is not really cheap but it has solved my problem very good. You could even keep the PVA inside the box during your print job, the filament runs through a tube to the feeder.

 

This has solved a lot of problems for me. You could also store the TPU or any other filament there which is prone to moisture.

Br

Thorsten 

Edited January 27, 2019 by Design94

[RudydG 62]

Drybox rules for long jobs (currently a 5 day job running without problems)

Currently 2 rolls of Polymax pla on the printer, and in the Drybox a roll of PVA and a roll of TPU95, both very sensitive, not like the Polymax.pla.

Edited January 27, 2019 by RudydG

[aag 6]

what do you think of the idea of improving the polybox by adding a Reptile Heating Pad?

[Smithy 1,144]

37 minutes ago, aag said:

what do you think of the idea of improving the polybox by adding a Reptile Heating Pad?

I don't think it is necessary, if you leave the spools in the box then nothing should happen and no need try extra dry them. If the spools have already absorbed too much moisture, then I would dry them in a food dryer or oven. 

 

I have no idea what heat a reptile pad can create, but sometimes you need 60-80° C to dry a spool and I am not sure if the bearings and the relatively thin plastic of the Polybox like so much heat for several hours.