Stick to 2.85mm - or else!

[boudlo 0]

Hello all – first post!

We recently bought three Ultimaker 2 machines to replace our old 3D Touch printers [shudder!]. I thought I would report my experience of installing and running the printers, simply to add to the knowledge base and hopefully others can avoid some of the pitfalls I fell into. Sometimes its difficult to identify the cause of problems when running a single machine, but if you are running three machines from new, all using the same filament and all three machines start to exhibit similar problems, then you can draw some pretty firm conclusions.

So, I set the printers up and printed the robot on all machines using the PLA supplied and the default settings in Cura. Brilliant results, so set about printing the large backlog of models we had waiting to be printed. About a week or so later, the quality of the prints began to decline – under-extrusion, print not sticking to the bed etc. - on all three machines. Scratched my head for a good while and then noticed that all the filament reels were down to perhaps the last 10%... I changed the reel on one machine and there was a marked improvement... changed the reels on the other two and we were printing again, but not without problems... still getting under-extrusion at times, clicking extruder, grinding out of the filament, printer finishing a successful print, but then refusing to extrude once a new model has been loaded...... lots of faffing about removing the bowden tube, checking that the extruder was not blocked, checking that the filament has not been “ground out” etc etc. To be honest, I was feeling a little disheartened..... these were the problems we had with the old printers...

Had a bit of a think and decided to remove the bowden tube from one of the printers and do a little experimentation. Still had a length of the original Ultimaker supplied filament from a fresh reel – pushed it through the bowden with little resistance.... cut off a piece of Ultimaker supplied filament from the “almost exhausted” reel and the difference in resistance was remarkable. The “almost exhausted” filament had a much tighter curve to it and was forming a “spring” inside the bowden, greatly increasing the drag, and hence the under-extrusion – one problem understood!

This still did not explain the reduced performance of the new reels of filament. We bought three of these machines from our supplier and negotiated a “sweetner” - they would supply two reels of free PLA with each machine, providing we bought three.... not bad eh! No!, the PLA they supplied was not 2.85mm but 3mm! Again, comparing the drag between the 2.85mm filament and the 3mm filament, the difference was substantial.... second problem understood!

We have since bought reels of PLA from a Dutch supplier advertised as 2.85mm and have three machines running with almost 100% reliability – we are very pleased with the Ultimaker 2.... its quite a step change from our old printers!

There does seem to be confusion about filament diameters and I note that the Ultimaker 2 manual still has on its specification page “ filament – 2.85mm [generally known as 3mm filament]”.... I think this is confusing should be changed to avoid frustration and reputation damage to a great printer – perhaps a sticker on the back of the machine saying “2.85mm filament only!”. I have read through lots of posts on the forum and cant help thinking that a lot of the problems might stem from trying to use 3mm filament as opposed to 2.85mm. I shudder to think what the Ultimaker support team has to go through trying to resolve this misunderstanding,

 

[gr5 2,005]

So quick summary:

1) Do not use truly 3mm filament! Must be 2.85 or 2.9. Actually it can be up to 3mm but never over - 3.0001mm is too much.

2) Last 10% of the spool/reel doesn't print well due to strong curvature.

 

[yellowshark 153]

Hi Boudio, one of the best filament makers is based in the UK, i.e. Faberdashery. I have been using them for about 18 months and have never had a problem, it is 2.85 and extremely consistent; I use the Dutch company too . For me Faberdashery has the advantage that you can buy the filament loose rather than wound on reels, so the problems with the last 10-20% do not exist.

 

[jonnybischof 60]

The bottomline is simple - Buy ONLY high quality 3D printing filament! - Sure you can get cheap stuff for half the price. But the trouble is never, ever, ever, ever worth it

All consumer grade 3D printers are made for either 1.75mm or 2.85mm filament (the latter is generally referred to as 3mm). 3.00mm filament doesn't have ANYTHING to do with 3D printers, instead that's what is used in plastic welding. These filaments usually also don't need to be manufactured to a very high diameter tolerance. Because it doesn't matter that much in plastic welding. But it does matter in 3D printing.

Any decent 3D printing filament is made to 2.85mm spec. If not - it's NOT 3D printing filament (even if someone might sell it as 3D printing filament).

/Edit:

I can also highly recommend Faberdashery PLA! Especially if you're in the UK and can save taxes and intl. shipping costs. It's expensive, but one of the best there is.

You'll need to print holders for the coiled filament (comes without spools) - but that's a good way to get rid of the cheap filament laying around

 

[boudlo 0]

Thanks for that Yellowshark

When I return to school next week, I'll order a 100M of the loose filament from Faberdashery and see how I get on. Can I ask if tangles are a problem with the loose stuff?

These new Ultimaker 2 printers are going down a storm in the classroom and I am just so impressed with what the students are producing. The combination of powerful design software [inventor] and reliable printing is a game changer.

 

[donmilne 2]

I refuse to buy filament advertised as being 3mm. I will not accept verbal assurances. My rationale is that if the order form says 3mm and receive 3mm then I have no grounds to complain. But, if I order 2.85mm and receive 3.00mm then I do.

 

[jonnybischof 60]

Thanks for that Yellowshark

When I return to school next week, I'll order a 100M of the loose filament from Faberdashery and see how I get on. Can I ask if tangles are a problem with the loose stuff?

These new Ultimaker 2 printers are going down a storm in the classroom and I am just so impressed with what the students are producing. The combination of powerful design software [inventor] and reliable printing is a game changer.

 

Tangles are actually a problem, depending on how you use the filament. If you use a holder for coiled filament you shouldn't have any problems.

I'm in the process of making a holder specifically aimed at solving these problems once and for all. Might take some more days though as I'm very busy atm...