PVA breaks & gets stuck in Bowden Tube

[voxycon 0]

Hi,

 

I am fairly new to 3D Printing, and have so far done about 15 Prints with the Ultimaker. Every time I tried to print with PVA overnight, the next morning I found the Printer with Error ER61 and PVA stuck in the tubes. The Print finishes, but I have to clean out the pipes after every print which gets tedious. The used PVA is straight from the Package, so I don't think the material can be the Problem here.

 

Because the print finishes, I suppose the problem is with the Material station when rolling up the unused Material. Also, after the print the Material doesn't get properly spooled up back on the roll but rather goes everywhere into the Material station - I don't know if this is an unrelated Problem.

 

Help would be appreciated!

 

Thanks in advance,

Jakob

[voxycon 0]

Btw the removed PVA has pressure points like seen in the picture, but also breaks in other places

[voxycon 0]

Problem still persists. I Upgraded to the newest firmware and the error changed to ER59, but the cause does not seem to have changed. No one any ideas on this?

[slarson 0]

My printer is doing the same thing.  Frustrating. 

 

[Carbon 28]

Are you both using Print Core BB0.4 or BB0.8? Are the print cores clean inside?

 

Are the pipes and guides free from blaokage? I only ask because as a piece of PVA broke off on the underside of our machine (feed paths) underneath the material station and was causing NO end of problems......similar to what you're both having.

[kmanstudios 1,120]

On 4/1/2021 at 11:38 AM, voxycon said:

Btw the removed PVA has pressure points like seen in the picture, but also breaks in other places

 That is grinding on the filament and can happen with any filament if the feeder is not properly adjusted. You can see that the grinding also creates raised areas that really make it difficult to move through the bowden tube. This then increases the likelihood of more grinding and can really make the filament hard to get out of the feeder or tube. I have even had to take the feeder apart to get the pieces that broke off, or just a lot of other debris that makes life much more difficult.

 

1 hour ago, Carbon said:

Are you both using Print Core BB0.4 or BB0.8? Are the print cores clean inside?

 

Are the pipes and guides free from blaokage? I only ask because as a piece of PVA broke off on the underside of our machine (feed paths) underneath the material station and was causing NO end of problems......similar to what you're both having.

This is solid on what to look for and do. 👍

[Michaelj2600 0]

I have exact the same problem as described by voxycon, and the picture match what I see, when I dissasemble the feeder to get the filament out of the tube again. Frustrating as I was really looking forwad to use the PVA as "suppert" material.

 

Could it be a heating or even more likely a humidity problem ?

When I load the material it flows fine, but during the first part of the print it gets stuck and not feeding - like the picture shows.

 

Its original Ultimaker PVA filament.

 

/Michael

Ps. Ultimaker 3 Ext.

[gr5 2,172]

It could be humidity, yes.  When you first feed it through the nozzle (you can do this in MOVE command on the display under the "..." for the matial type) do you see any steam coming out of the nozzle?  If so then it is too wet.  If you hear sizzling, popping, really any sound at all other than the feeder, then it's even worse than simply too wet.

 

You can dry PVA.  Look in cura at how many meters you need.  Unspool that amount onto the print bed and place the spool on top (no need to cut the filament).  Then heat to 70C, cover with a few towels, a pillow, sheets, paper towels.  Something.  Some kind of insulation.  Even some cardboard.  Leave it like that for 2 to 5 hours and it should print fine.  To dry the whoie spool it needs something like a few days as it takes a very long time (days) to get the humidity out if it is deep in the spool.  Easier to just dry what you need.

 

Going forward you want at least 1/4 cup of color-changing-dessicant in a ziplock bag with your spools of PVA or Nylon.  You can buy it by the liter/quart.  When the color changes you have to heat it back up on a heated bed or in the microwave (in a non metalic, non meltable container such as a glass bowl).

 

[RudydG 62]

Pva is a wonderfull material, but you have to master it. It can be to dry (breaking) or to humid (mushy)

I only unload the needed length and cut that of the reel, the rest goes back in the sealed bag. Even a couple of hours outside the bag can ruin the expensive material.

 

 

[rachael7 73]

I had the same issue, through 3 different rolls of UM PVA. I think the material is just unsuitable for the material station. Somebody must be using it successfully, but it sure isn't me. After killing a pre-feeder, clearing countless jams, changing to the fine knurl feeders, and taking the material station apart 3 times to clear really stuck jams, I finally gave up on the UM PVA altogether. I'm using BASF BVOH soluble filament now, along with AquaSys120 soluble for high temp filaments, and all my soluble support jams have gone away. Both print just as well as the UM PVA, too.  The AquaSys120 is pretty expensive, but the BASF BVOH is reasonable enough, and given the time and headaches they've saved me, both are well worth it.

[Kvanwem 2]

This issue has been going on for me since I bought the S3. I have spent more time clearing jams than printing with the material. I think I'll try what Rachael7 suggests and order some of the BASF BVOH and see how that works. 

I am in AZ so I think that the PVA gets dried out making it more brittle. I would sure like to know how Ultamaker did the print in the demo video without a failure. I guess if you can put this in a strictly controlled environment it may work.

[Kvanwem 2]

4 hours ago, Kvanwem said:

This issue has been going on for me since I bought the S3. I have spent more time clearing jams than printing with the material. I think I'll try what Rachael7 suggests and order some of the BASF BVOH and see how that works. 

I am in AZ so I think that the PVA gets dried out making it more brittle. I would sure like to know how Ultamaker did the print in the demo video without a failure. I guess if you can put this in a strictly controlled environment it may work.

 

I was pondering this whole PVA breaking thing and thought what if I warmed it up first? I took a piece and hit it whoth a heat gun and, as expected it became more pliable. So I put the spool on the build plate and set the temp to 60-C, let it warm up for 10 minutes or so and it appears to have worked. 

I am at the end of a 4 hour print of an articulated Rocktopus (don't ask), and the PVA is working great with no breaks or jams. Perhaps warming it acted as a tempering, removing some of the stresses in the coils.

 

Hope this hope this helps someone.

[subnoizellc 2]

I have found that when I leave the Ultimaker PVA in the material station it drys out and becomes very brittle. Glass like, actually. I take it out and leave it in a sealed bag when not in use.

 

Also, before I place the PVA into the printer I do a test, I bend it and if it can't make a shallow arc without fractures appearing or it just outright snapping I leave it out for a few hours to a few days depending on the humidity.

 

Ultimaker PVA is wonderfully brittle and almost crystal like when dry. Which makes it a great support material. Problem is when it's too dry, it shatters like glass!! It almost requires safety glasses in that state! It will shatter and sling out tiny fragments in all directions. Kind of like exploding.

 

So what is too wet Ultimaker PVA? If you can tie it in a knot, way too wet. If it can do the shallow arcs without fractures, then that is "wet enough."

 

Ultimaker PVA isn't like that stuff others sell that smells like a wet dog and feels like a wet noodle. This stuff rocks!

[dsp 18]

we had some problems in the past using PVA as well,

I have solved this by heating the spool up to 45° C for around 4 hours before printing and no more issues here.