UM3-Extended was a huge expensive mistake

[Fnord 1]

I hate to say it, but I screwed up. I bought the Ultimaker dual extrusion marketing hype and even got our school to spend its very limited technology funds on the Ultimaker 3 Extended.

 

I am posting this anonymously because I don't want the blame for wasting thousands of dollars on this joke of a technology to come back to haunt me.

 

 

The PVA support material and the "dual-head extruder technology" HAS NEVER WORKED PROPERLY as the marketing claims.

 

The PVA support material is extremely difficult to work with. It MUST stay absolutely dry or you will have problems. 

 

If you live in any part of the world other than the Sahara desert, the PVA is going to start absorbing moisture out of the air the instant you open the filament packaging, and the PVA is going to fail to work properly. Your printed material will have what looks like pieces of cotton candy all over the place, and the PVA extruder will randomly plug up in the middle of a job and fail to support the workpiece.

 

We bought the Ultimaker 3 Extended to print some really large and complex engineering models and show what 3D printing can do, but in fact I have never been able to get the PVA to work long enough to produce a column more than about 5-10 cm tall before the PVA head plugs up and the print fails, even with the optional PVA extruder column that forcibly wastes PVA by printing a column of useless material for each layer.

 

After being exposed to the open air in an air-conditioned classroom for about 3 months, the PVA absorbs so much moisture that it becomes soft and bendy like aldente pasta. And of course by this point the PVA is completely useless for printing as the moisture will make the printhead spit, bubble, and burn.

 

 

We are out thousands of dollars for a hyped-up 3D printer and its "water dissolving" support material that are essentially completely useless, because we can't run the 3D printer and/or store it in an absolute zero humidity environment at all times.

 

Our fault apparently. Or maybe we're "just not using it enough", which apparently means going through a full roll of PVA in a day or so, and then discarding what's left.

 

Small printing projects spread out over many days to weeks that barely uses any PVA, will almost guarantee the reel of PVA sitting on the back of the printer is going to absorb moisture and not work properly.

 

 

If it were possible I would demand a refund for a lemon of a product that cannot do what the marketing videos claim, unless you take extreme measures to run it in an absolute zero humidity working environment. But the thing is about two years old now, so..

[Smithy 1,135]

I don't really understand your reaction. You don't have a problem with the printer, you have a problem with the PVA material. Yes it absorbs quickly and a lot of moisture from the air, that is also the reason it should be stored in a dry place and for longer prints also during printing. Thats not the fault of Ultimaker, it is a property of the PVA material. It would be the same, if someone is printing PLA and then rant because PLA gets soft in a hot car.

 

You should always store the PVA spool in an airtight bag or box, with some silica packs to keep it dry. And if you are in an area with high humidity, then you should buy a Polybox, whch keeps the spool dry during printing.

 

Thousends of users are able to print successful with the UM3 and PVA, you just have to handle it in the right way.

[Fnord 1]

The hardware should not be "defective by design", which then forces end-users to have to buy or build weird custom add-ons or have to treat the filament like a delicate fragile snowflake.

 

 

Why does the device not ship with a sealed, gasketed reel enclosure designed to keep moisture away from the PVA reel? Hanging PVA on the back as designed is ridiculous for anywhere on the planet that it rains or is foggy occasionally, as any high humidity rapidly ruins PVA.

 

Ink cartridges commonly use extremely long thin labyrinth breather tubes to slow the loss of moisture as ink is used. A sealed reel enclosure shipped with the machine could use a labyrinth breather tube to slow the absorption of moisture as the media feeds out.

 

It should be standard procedure to open a sealed PVA reel package, put the reel in the enclosure and then take a large silica bag out of the reel packaging and put the silica bag in the enclosure with the reel.

 

Why isn't the entire PVA filament path made as air-tight as possible from a sealed reel enclosure, to a motorized feeder with an airtight gasketed cover enclosing it, to a feed tube gasketed to the printhead heater, so that PVA can be left installed at all times and it still works, even in a high humidity environment?

 

 

But no, we have to instead go through all sorts of extra special handling steps and build additional homemade filament storage or entire-device dry-box enclosures that should have shipped with the hardware as standard.

 

[Smithy 1,135]

There are so much possibilites to use a dual head printer, so I see no need to build something special for PVA. A lot of users are using two colors or BreakAway as support material and they just use the spool holder on the back. So why should they all pay for additional harware, when they don't need it. 

 

Handling PVA is not diffucult, it is also not so sensitive that you have to take special preparations when opening the package. You want just keep it dry, an airtight freezer bag is enough, no need to buy or build special equipment. For longer prints put the spool in the Polybox, that's it.

 

BTW you can also regenerate your PVA in an oven or put the spool on the heated bed and cover it with a towel and leave it there over night.

 

If you want to have a ready to go solution, then you should consider to buy an S5 with the material station.

[gr5 2,005]

5 hours ago, Smithy said:

BTW you can also regenerate your PVA in an oven or put the spool on the heated bed and cover it with a towel and leave it there over night.

This.  Do this.  I recommend 70C and use the heated bed already part of the UM3.  If you don't have access to a towel at work you can put it in a cardboard box.  If it's really like al dente pasta it might take 48 hours but it's very easy to do.  I'm not 100% sure you can recover it if it gets this bad as I've had it bad enough that it sizzles and spits but not so bad that it was as soft as you describe but it's worth a shot as it only takes a few minutes to toss the spool in a box or under a towel and forget about it.

 

After drying it, it should last at least 24 hours if not 48 before needing to be dried again.  Or just put it in a sealed 2 gallon zip lock (even without dessicant) within a few hours.

 

However I partly agree with you - for a school, it's so much better to buy 3 um2go's than one um3.

[LaserBrain 2]

You can also re-purpose a food de-hydrator...

 

 

[Smithy 1,135]

Yes, just be careful they often overshoot the target temp and then you get this:

[LaserBrain 2]

eek!

[gr5 2,005]

lol.  But you still use it, right @Smithy?  What temp did you dry it at?

 

[Smithy 1,135]

Dried it at 70°C (Nylon) and yes filament is ok -  I still use it.

It is just the spool, but it works, ok maybe not in a dual setup on the original spool holder 🙂 

 

[DivingDuck 87]

Filament spool artwork 🙂

[gr5 2,005]

I actually dried a spool just like that at 70C overnight last night and it looks fine.  UM clear nylon.