How old is your PVA and do you store it in a dry sealed box? If not your spool has probably absorbed too much moisture and you need to dry it.
Another possibility could be that your BB core needs cleaning. Follow the UM instructions for hot/cold pulls.
Does anyone have experience keeping PVA in the material station for long periods of time? (3-6 months)
I use PVA rarely and have trouble making it thorough a whole roll before the roll takes up enough moisture that it's fubar. I guess I could use newer smaller rolls of PVA but I have some big ones around still shrink wrapped that I'm debating opening. Haven't used PVA since I added the material station and was hoping the community could guide me before I burn a roll on a single print only to find it fouled 3 months later.
Also if I have an old roll that's taken up some ambient moisture, will leaving it in the material station resurrect the roll? I've historically been pretty unsuccessful drying them out in the over etc.
Thanks to anyone who lends advice!
I can absolutely recommend the material station, but not the Ultimaker PVA in combination with the material station. For a long time, I only used the Ultimaker PVA by using filament boxes with silica gel bags. There were never any problems because I could ensure that the filament was not under tension with the position of the boxes.
Then I upgraded my first S5 with a material station. I now find the material station great and will probably equip future S5 printers with it as well.
However, the Ultimaker PVA becomes too brittle over time in the material station and often breaks. After only about 3 weeks, I noticed an increased risk of the filament breaking. This happens especially when the material is loaded all the way from the station to the nozzle. Therefore, it is recommended to print with the PVA approximately every 3 days. Then the material is not discharged and remains in the nozzle. Rolls straight from the packaging can be used directly. I would possibly heat these briefly for a few minutes to reduce the risk of breaking. For 3 minutes at 50°C in an oven or similar.
I leave PVA permanently in the station, regardless of the manufacturer. There is no need to worry about this. With Ultimaker PVA, if I haven't printed with it for a while, I heat it briefly as described before a print.
Although the Ultimaker PVA is even my favourite in terms of residue-free dissolution, I switched manufacturers for PVA. All the manufacturers I have bought PVA from have a softer filament which has never broken in the material station.
For the best PVA printing experience, I can recommend BASF's BVOH. It prints great with the 0.4mm nozzle, doesn't clog and offers a very worry-free working experience. Unfortunately, it is quite expensive and, like all other manufacturers except Ultimaker PVA, dissolves in an opaque, milky soup.
Polymaker's PVA S1 should be the cheaper option. I have used it in the past, but not yet tested it with the material station. However, I know that there would be no problems here. It's also softer so it won't break, leaves a few threads which don't dissolve completely but wash off and is one of the cheaper options.
Personally, I switched to a German manufacturer who only sells nationally.
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Gero, Thanks for the comprehensive reply and recommendations.
- When using another brand of PVA are you still using a BB core? I guess I don't really know what's special about a BB core pairing with PVA. I would assume I should use my BB core for all PVAs regardless of manufacturer.
- You're situations sounds much like mine where you had an S5 and then got the material station. Some S5s that were made earlier had a more coarse gear on the knurled mechanism for the feeder. Ultimaker offered an upgrade to a finer knurl on the exturder and I'm curious to know if you have a newer S5 with the finer knurl or an earlier model. (https://support.ultimaker.com/hc/en-us/articles/360015621060-PVA-material-breaking-in-the-Material-Station)
- When using other brands of PVA in the Material Station do you just use an unmodified 'Generic PVA' profile?
Thanks much,
Happy New Years.
DR
Regardless of the manufacturer, the BB Printcore should be used for PVA. The nozzle in the BB Printcore has a slightly different internal layout which should prevent nozzle clogging.
My S5 is already from the updated model range. I cannot say whether the feeder caused more problems before, but I can say that the problem is not completely eliminated with the new feeder. Having to watch his S5 with a material station to make sure there are no problems with the PVA has irritated me a bit in terms of use.
When loading, I specify the generic PVA profile. Since Cura sees the loaded materials, I always select the right combination of materials that I need.
I would still recommend a one-time temperature tower when choosing a different PVA manufacturer. Although pretty much all PVAs can be printed with the standard PVA profile, it can help to adjust the temperature more accurately. For example, I have found that with one manufacturer I have more precise and clean prints with a temperature of 200°C instead of the 225°C in the standard profile.
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On 12/31/2021 at 2:29 PM, Smithy said:How old is your PVA and do you store it in a dry sealed box? If not your spool has probably absorbed too much moisture and you need to dry it.
Another possibility could be that your BB core needs cleaning. Follow the UM instructions for hot/cold pulls.
Brand new 500g PVA spool and BB core. I cleaned the core after each attempt. It still hapends.
Edited by ACDCCThanks for the input fellas. Very much appreciated.
@SandervG Does PVA ooze more than other materials? I have another post where I ask about oozing in general, but from watching my printer, I suspect that the PVA oozes more than the PLA. Or perhaps the BB print core oozes more than an AA core? Do you have any data on this?
Like Gero, I had no end of problems with the UM PVA breaking in my S5 w/Material Station. It was near constant, probably every 2nd or 3rd print. After countless jam clearing, 3 disassemblies of the material station, a dead pre-feeder, switching to the fine knurl feeders, and more cursing than I care to think about, I finally tossed two sealed rolls of it in the trash - it was that bad. It prints nice, when it doesn't break, and it dissolves nicely as well, but it takes so much extra work to deal with the stuff and puts the machine at so much risk, it really just isn't worth it. I'm honestly surprised UM hasn't changed the formula to soften it up on the spool, given the massive number of problems people are having with it. I switched to the BASF brand BVOH, and like Gero, I find it does everything you would want it to do - it just works. Yes, it is more expensive than the UM PVA, but it has more than paid me back in the time and frustration it's saved. I make my own NFT tags for the spools, so they are recognized in the material station just like any of the UM materials and I just couldn't be happier with the change.
Has any one managed to print Ultimaker PVA at 0.06mm or 0.1 and short lengths?
I have a part that has to be with a tolerance of 0,1mm. The PLA prints perfect but the support is bad, it doesn't extrude the material correctly. This is with the prime tower.
I have noticed that on short lengths (5.5mm) it doesn't work well. The prime tower is perfect, but the support isnt.
Any advice?
@ACDCC Yes. I printed the hen-hen https://www.thingiverse.com/thing:2673771 at Cura set to the visual profile at 0.6mm with a prime tower. I scaled the model to 175% (I think). I used Ultimaker white PLA and Ultimaker PVA and the result almost came out looking like it had been done on a resin printer. That 0.6mm setting is frieking amazing.
I had a heck of a time with bed adhesion. I tried to print it without supports, then with minimal supports, then full supports but no tower, and I finally got it to print with Ultimaker's default supports + adhesion* + prime tower + 3DLAC. * Whenever I use adhesion + support PVA, I set the brim extruder to use the PVA so I don't have to cut off the brim.
This particular model has some very narrow "legs" which caused the trouble. The PVA seems to ooze a lot. So when I printed it without the tower, the oozed PVA filament would rub against the previous layer and knock it off and the whole model failed from there. The tower wiped the oozed PVA off and solved the problem.
The prime tower always seems to come out looking perfect. Looking at it you would think "Oh, you didn't need to do that" but yes I did. I have not needed to use a prime tower on any other PVA prints. In other prints, even if the PVA comes out looking poor, the resulting model is fine.
QuoteI have noticed that on short lengths (5.5mm) it doesn't work well.
You could increase "Support Horizontal Expansion" from the default of 3mm to something larger, which would force more support material to be used. You could also increase the size of the tower to waste yet more material. But that seems like a workaround for a more fundamental problem.
Quoteit doesn't extrude the material correctly
Can you explain more and post a picture? It sounds like PVA just isn't extruding correctly. My PVA is <1 month old and stays in the bag with like 10+ desiccant packs. So far so good. You could also try Polymaker PolyDissolve, which has a reputation for not absorbing moisture as quickly as Ultimaker PVA.
@MobyDisk Thanks for the reply.
I had the same idea about the support horizontal expansion, and i increased it before starting my second attempt. Will se how it comes out tomorrow.
As for the extruding problem.
After my first attempt i printed a different part at 0.1mm using the same PVA spool and it came out perfect. So i dont believe it's the spool. ( is there a way to see the production date of the spool? )
The problem comes when it has to create the support inside the part ( picture a rectangle with one side open ). The printer goes along the path of the support buth extrudes just a few mm of material and the jumps to the next. After it skips a layer the rest ( if material extruded ) are useless. Meanwhile the prime tower is perfect.
Sorry i cant provide pictures, im at home now and the printer is at work.
Hello all, I've been having trouble with our PVA support coming out looking like sugar crystals on some parts of the print and not supporting the PLA. Have also experienced some filament breakages in the lines from the material station (it seems very brittle?). I tried drying out the spool at 55°c in our oven for a few hours and this didn't make any difference. The spool is a few months old and has always been kept in the material station. Thanks.
55C for a few hours will do almost nothing.
Unspool the amount of PVA you need and place it on the print bed with the spool sitting on top (partly to keep the spool from getting as hot as the spool itself can warp a little (not a huge deal) at 70C). Try 70C for 4 hours. Cover with 5cm of towels or blankets.
To dry an entire spool takes around 24 hours. Probably longer - that will get the outer cm or so.
7 hours ago, Andrew_W said:Hello all, I've been having trouble with our PVA support coming out looking like sugar crystals on some parts of the print and not supporting the PLA. Have also experienced some filament breakages in the lines from the material station (it seems very brittle?). I tried drying out the spool at 55°c in our oven for a few hours and this didn't make any difference. The spool is a few months old and has always been kept in the material station. Thanks.
I’ve had nothing but problems with UM PVA. I literally threw out three spools of it because it kept breaking, jamming, and otherwise failing to print. I switched to BVOH filament from BASF and I’ve never looked back. Night and day better performance and no breakage.
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im trying to figure out on where is the spot to print something.
1 hour ago, East71653 said:im trying to figure out on where is the spot to print something.
This sounds off topic. Are you talking about water soluble support filament? If not please post in a new topic. And please include more description and some screenshots or photos would help explain your issue.
On 4/25/2022 at 11:17 PM, gr5 said:55C for a few hours will do almost nothing.
Unspool the amount of PVA you need and place it on the print bed with the spool sitting on top (partly to keep the spool from getting as hot as the spool itself can warp a little (not a huge deal) at 70C). Try 70C for 4 hours. Cover with 5cm of towels or blankets.
To dry an entire spool takes around 24 hours. Probably longer - that will get the outer cm or so.
Thanks for the info. We have several ovens at my work place that I can leave the entire spool in for extended periods of time (>24hrs). What safe temp would be recommended for a long drying session of an entire spool?
I'll also try the unwinding the amount (plus extra) for another build and placing it on the build plate beforehand.
@Andrew_W: We recommend to dry the material at 50C, preferably also for longer times (overnight). Additional benefit is that this should relax stresses in the material, leading to reducing brittleness.
The trick is with PVA to dry the material without crystallizing it, PVA is a semicrystalline material, and will crystallize when heated over 55C for longer times. Crystalline PVA will become stiffer and brittle, so that's also undesired.
Moisture will lead to enhanced degradation during printing (e.g. the 'sugar crystals' you are referring to). Luckily, Ultimaker PVA doesn't absorb moisture as fast as other PVA filaments. In addition, there are no additives in Ultimaker PVA, which makes handling a bit more difficult but it is safer to print and easy to handle the water which was used for dissolving PVA (this is always a trade-off in soluble support filaments - it depends where the manufacturer focusses on).
Hope this background information helps a bit!
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So I don't usa a lot of PVA. I didn't know about the 55C issue. But I dry Nylon at 70C maybe 10 times per year and overnight at 70C doesn't penetrate very far into the spool but if I unspool it I can get it nice and dry in just 4 hours.
I suspect drying PVA at 50C overnight while tightly spooled will not penetrate more than the outer layer. I also suspect that even if you unspool it's going to take 4 to 15 hours but I don't have any data for PVA. Just Nylon.
So I recommend you do 50C, unspooled (in Cura you can see how many meters are needed and just unspool that much, overnight, on the bed under towels or in an accurate (non gas as that is humid) oven as a test to see if this solves your printing issue.
Note that PVA and PLA do not stick together all that great. PLA usually prints over PVA reasonably well but the other way around not so much. It usually works but it is a bit tentative. This is why the PVA profiles in cura all have "support horizontal expansion" set to 3mm - to get the PVA to stick out and reach down to the print bed (for most models but not all).
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@gr5: So about Nylon you're absolutely right. There is no problem in drying Nylon at 70C. If you dry Ultimaker Nylon transparant, you will see it become a bit more milky (crystals formed in the filament). Also, the filament should be a bit stiffer.
For printing, it doesn't matter that much since you melt the filament again in the printhead, so the Nylon crystals get molten anyway. That's the tricky part about PVA.
About drying, two main considerations:
- Heat: this reduced the relative humidity and enhances the moisture diffusion through the filament (especially close and above the Tg of Nylon / PVA 50~60C).
- Convection: by having air flow around the filament you remove the moisture coming out from the filament. So indeed a tightly spooled filament coil will take up moisture on the outside first, but will also dry on the outside first. If it's moist also on the inner filament, it's more difficult to dry those parts as well (unspooling or loosening it up can help - so at least some air flow can reach the inner filament too).
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I want to know why we all have such different experiences. Could someone post a 3MF file and we can all test print the exact same model with the same PLA and the same PVA, and post videos of the print?
When I purchased my printer I straight-away bought a spool of polymaker PVA because I had heard bad things about the Ultimaker PVA absorbing humidity. But since I have had almost no problems, I haven't even opened the polymaker. So far I have only printed with PLA in the winter. I wonder what the relative humidity is in our various places? I don't see how heating filament to 55C and sitting it somewhere will help if the relative humidity in the room is 80%.
I've had great luck with the Ultimaker PVA, and I'll probably keep using it despite it being significantly higher in price than other brands because, well, it works well, and in the Ain't Broke Don't Fix It category.
Any soluble support material of any brand will absorb H2O from the room air. On a couple of occasions, like when I have not used it for a few weeks, I'll pop it in the air fryer, set it on dehydrate at 105F, and let it run six hours.
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ACDCC 0
HI,
My PVA clogs the nossle (BB 0.4mm) 30min to an hour in printing.
It's like baked.
Any recommendations?
Edited by ACDCCLink to post
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