Using PVA on a Looong print?

[shaund 0]

Having had Ultimaker 2+'s before, I just bit the bullet and got a new Ultimaker 3 extended!

 

For the first couple of big prints that I've generated, Cura is coming back with print times in days and not hours :(

 

With this in mind, I was thinking that there's a good chance that with that amount of time exposed to the air sat on the back of the printer, my PVA is gonna be in a pretty poor state by the end, so my question is this - what do you do when you've got a long print using PVA?

 

Are my concerns real?

Is this a non-starter beyond a certain time period? Would I have to pause the print, remove the spool and bake some moisture out?

I'm also thinking about getting some 0.8mm cores so does that make my life easier in this case or worse?

 

I've got both Ultimaker PVA and some Formfutura stuff so not sure if they're going to behave differently..but either way, I dont want to come back to a print after a day or so and find that the support materials not extruding/jammed or fizzing all over the printbed..

 

Thanks in advance..

 

Shaun

[mattgriffin 28]

Hey Shaun!

There are a few answers there -- some high-tech solutions and some practical solutions. But it really comes down to the environment around your printer. If you are in, say, Arizona, you can basically ignore the worry and print away! If you are in Malaysia, you'd better come up with an end to end sealed filament box chock full of dessicant to help counteract the hygroscopic thirst of that material. There are a bunch of PVAs and some are thirstier than others. I have found the Ultimaker PVA a bit hardier than I'm used to from the early days of desktop 3D printing and PVA, but I defer to other's more recent experiences for formfutura etc.

 

I print multiple day prints with PVA all the time in Brooklyn, sometimes in my apartment that occasionally is blasted by steam heat (not too effective for heat, but hey), and sometimes at New Lab where humidity seems fairly consistent. And I haven't seen print-destroying degradation during long prints. I usually mess up my PVA when I complete a cool project and leave the PVA on the spool when I go on the road for a few weeks. d'oh!  So remember when you aren't using it to box it up. And get it fully out of that BB core!

 

If humidity where you print is a tough issue, you might consider grabbing one of those food dehydrators like PrintDry kit Matterhackers offers. That gives you a shot to dry it out. It maybe just cargo cult, but this seems to restore waterlogged PVA spools better than the build-plate trick. But there are community members and staff here who swear by the overnight build plate trick. 

There are some great PVA resources in this forums AMA event from this past summer: