PaulK

As far as I can see, the basic problem is that a fixed value doesn't really do the trick. Ultimately it depends on filament, settings *and* geometry, and the geometry is what really throws it all for a loop. I look forward to the day when the software can analyze the geometry and adjust automatically (to within what you know about the filament, etc)

Will this step on my custom materials and printers defined in Beta 2?

I'm interested

At least some kinds of PLA i've had consistently get brittle with age, whether on the spool on in printed form. Lots of people kind of deny it, so I'm not sure if they haven't had printed PLA things aged a good amount of time, or if it is formulation issue, or environmental, but for sure some of it does. Also, if I leave a roll of PLA on my machine for a while, it will almost surely break where it is stressed in a week or two (this is on my other non-UM machine, 1.75mm). I've had PVA break at the extruder many many times when first loading. Sometimes I just cut off the first meter now if I haven't used it in a while. I think one issue with that is when the UM unloads the PVA, the 'cold-ish-pull" it tends to do can grind a dent into the PVA -- I've observed it. That becomes a weak point. The new firmware tends to lessen that as the filament tends to pull a lot easier on unload. Just my experience.

Larger parts exert a LOT more force on the corners/edges. It sounds like just a bed adhesion problem, where you have enough for smaller parts but the big ones are getting you. The usual solutions -- brims, adhesion help, more squished first layers, etc. will probably do the trick. You can get pretty big with PLA and survive it if you can get the adhesion.

You don't say what printer or material, but here is a completely random possibility when this started happening to me recently when normally I am fighting to get PLA off the bed. I had dual extruder set up, one PLA, one ABS. I was printing something *entirely* in PLA, but because the ABS extruder wasn't disabled, Cura heated the bed up to ABS temp (Cura, please don't do this!). Turns out PLA will adhere to a bed this hot (I think it was 85 or something), but it is reaaaal soft and tends to curl up and corners. Of course, there about a zillion other reasons too.

I seem to be stuck with an unloaded filament but can't convince Cura + firmaware to let me print. I had nylon loaded in #2. I've since disabled #2 to print some #1 PLA. If we drop down the printer, it knows there is nothing in #2: However, I select that configuration (Whilte PLA + none), it doesn't take ... It still thinks there is nylon. This is also in spite of the extruder being disabled (I could go on at length at how bad Cura is when you have a single filament print but two things loaded ... like using the higher bed temp of the two, despite one of them being unused....). I select the config, and it remains convinced nylon is loaded. Then, if I print ... Short of lying about nylon being loaded, I'm not even sure how to get it to print (though haven't tried that hard) Basically I cannot convince Cura that nothing is loaded in #2 PK

Upgrading form Beta 1 to Beta 2 dumped my custom printer definition and all custom materials. This is .. disappointing. And quite a bit of work. Are they still lurking around somewhere by any chance? Windows.

When I went to swap out my AA0.25 Core with the new firmware, it had left a string down into the core that was stuck pretty good. I had to remove the bowden tube and clip the string to get the core out. Note I have only ever printed a single type of filament with this core, so there was no contamination etc. Now this could be a one time thing, but never happened with the old core swap routine. It's like it allowed too much (or not enough?) cool down before retracting to its resting position. Or just unlucky. The 0.25 core can be a little finicky. Over all I do like the large retraction though.

I just got a false material out print pause (S5). Loaded materials were White PLA and Ulitmaker PVA. I'd be betting the PVA was the problem; the only other time I've got this was printing transparent CPE. So that fix isn't all the way there yet. Mmmmm .... I'm gonna reserve judgement. Let me get back to you. The white was actually feeding very poorly in this case (hard to tell why), it might have been legit.

When I selected Sprint 0.4, it shows 0.2 in the title.

S5 #1 -- Did a core change (to 0.8). It did not retract the material enough to do the core change, I had to manually release the filament and pull it back. #2 -- it said I shouldn't do white PLA + 0.8. I think that is bogus. This is why we buy 0.8 nozzles. Added: DOH. Don't drink and print. Loaded a BB 0.8 core, which is, indeed, a bad idea for white PLA. #3 -- It keeps prompting me to "upgrade" to 5.1.whatever. This isn't helpful.

If you have a printer that prints ABS well, it is a nice filament (outside maybe the smell). It feels "good in the hand", has nice surfaces, has enough flex to be tough in lots of situations, is relatively easy to work, has good temperature resistance, etc. Its actually quite a nice filament. Coloration tends to be very solid and nice. It doesn't get brittle, a real problem I've had with PLA over time. Warping, especially on certain prints, can bit its real bug-a-boo. But lots of PLA alternatives have that problem. HOWEVER, if your printer isn't in love with ABS, it can be a serious PITA. Both of my printers print it easily (my first printer, mostly due to a lack of a print cooling fan, printed ABS much better then PLA until I added one) and I have not fount CPE/PETG to be significantly easier. But lots of people have layer adhesion problems, bed adhesion problems, extreme warping, etc. So, YMMV.

I'm stuck on "Updating firmware" for about 4+ hours now. One hates to power cycle it, but its hard to believe its going to complete, either. Is there a timeout eventually? I can reach the printer via WiFi no problem, go to cura connect, etc About still lists "Firmware version: 5.1.8.20181207" Added: Try 2 made it go. Unfortunately there are no hints as to why try 1 failed.

Yes, limiting combing made it pretty much perfect, you'd be hard pressed to find the seam now. The strength is back too, not surprisingly. Thanks!

Yah, it is about a 2-3cm move (combing) to get to that point. I though that might be it too, so I put in a various values for "Retraction Extra Prime Amount" and it made no difference. Sigh. I just kept reading "Extra Prime Amount", and ignoring the "Retraction"; of course there is no retraction in this case, hence why it made no difference. DOH. Some days I am just dumb. Or at least get a blind spot, when you get convinced you know what the problem is but not paying attention to the solution you think fixes it. Max Comb Distance is excessively hidden, it isn't even in expert settings. I'm trying out 10 right now.

Material is ABS. Printer is direct drive mostly home-grown. Prints well with Simplify3D, I'm trying to dial in a profile in Cura so I only use one slicer. Retraction is enabled, 1.4mm (same as Simplify3d) The picture is a print which has been snapped off at its weakest point. The ... weak bit we see here is the *beginning* of the perimeter, i.e. it is where Cura starts a perimeter. Now one problem here is that by starting all there perimeters in the same spot it creates weakness, but this is also a terrible start to the perimeter. I've tried upping the extra prime amount to a LOT (10 mm^3) and it had no effect at all, all the prints look like this. It really looks like under extrusion at the start, but there is no evidence of under extrusion anywhere else. Ideas on what needs adjusted here?

It might be nice if Cura allowed the cool down bed temp to actually be higher instead of off; I'm pretty sure there is a temp for PETG that allows reasonable removal but minimizes chipping. Some filaments even recommend not allowing full cool down before removal.

Ya know, suggesting that those with different findings then you must not care about quality is not the way to go about this.

I guess our experiences are different. I've never had a spool tangle and found, properly mounted, that a spool feeds extremely consistently, possibly excepting when you get very close to the hub on some smaller spools where the bend of the filament wants to fight everything. That would be the case no matter how you were containing your filament. Different things work for different people, probably due to different needs and setups.

I'm really surprised that works for you. If I take a length of 3mm filament off spool, it'll try to make its way across the room and catch up on anything. The filament has to be contained someway, how are you containing it?

Are you suggesting to print without spools? What would the alternative be? I've not noticed small tangles on spools which are carefully mounted. I've had some mounting systems on my other printer that gave me grief, but 1.75mm filament (which it uses) also seems a little more likely to do that.

The clamps are fully adjustable from basically none (allows insertion of the tube) to quite tight. The outer cap controls that. The spools run very smoothly, all unwinding resistance will completely depend on how much PTFE you use. The resistance is extremely low (dependent on how much PTFE you use) and very even. The spools don't hang loose on the rod (which is aluminum shower rod), they have an insert customized to the spool so that it runs evenly on the rod and the spools don't hang here and there. There are free turning spacers between the spools to ensure they don't interfere with each other.

Among many other things, I’ve been making dry boxes.. the meter was moved outside through the box in the close up. Each box with 4 reels takes about 38 printed parts plus some shower rod and screws/nuts and silica gel. I’m going to have 3 boxes of ready to go filament. Probably won’t store PLA in there The PTFE can go all the way to the extruder (swap out the short piece for a long one). Humidity in the box is running 17%. I’ll need to add a shelf on the back of the machine stand to hold it. This should make things more reliable without worrying about humidity. We will see how it all works out.

I had this happen today. There was no filament out, though it could have been slipping or something; i'm not sure if the sensor is optical or a mechanical wheel. It happened 3 times on a print. I was printing PLA+PVA. The PVA is reasonably dry and seems to print OK. Cura Connect on the printer is not happy; I can no longer reliably connect to it, and when I can, it logs a lot of errors about not being able to get maintenance history and not being able to get status, though mostly I can't view the logs or the printer (this is all through the web page at the printer address). I can't verify if network is associated with, not enough data, but will say I'm getting at the same time as cura connect misbehaving.