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Tobus

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Posts posted by Tobus

  1. OK, I tried tightening the feeder tension a bit more, and all was going well until about an hour into the print, where I ran into extrusion problems again. This time it didn't chew through the filament (though I did see where the teeth marks had gone back and forth over the same piece several times).

    I had noticed low extrusion early on in the print, so I tuned it to 105% material flow. That didn't do much, so I upped the temperature from 210 to 220 and backed the material flow back to 100%. The higher temperature worked for a while, but then for no explainable reason, it just started thinning out and stopped extruding altogether.

    So now I'm really confused as to where the problem lies. Since it didn't chew through the filament this time, it appears to still be feeding. But not extruding.

    My UM2-E came with a spare nozzle, spring, isolator, and other hot-end parts. Is it worth just swapping those out and seeing if it fixes the problem? If so, where would I find instructions on how to do this?

  2. I'm at my wit's end with this.

    I'm using an Ultimaker 2-Extended that I've had for about 2 months. Current stats are 347 hours on, 318 hours printing, 246 meters of material. In the past week or so, I've started to run into big problems with extrusion, where it will just start to spit out thin blobby strings and then stop extruding altogether. The culprit seems to be the feeder motor chewing through the filament and not being able to feed.

    I did several "atomic" pulls, and everything looks good there. I'm certain my teflon isolator is not at issue here, as I can easily hand-push the filament through when the nozzle is hot. It extrudes nicely and I cannot detect any reason that the hot end would be to blame here.

    I ran a lightly oiled swab through my Bowden tube, and even greased the spool holder to make sure there was minimal friction for the feeder to fight. Everything moves like butter.

    Then I adjusted the knurled feeder wheel tension a little tighter to give it more grip on the filament - about a third of the way to maximum. That seemed to help a little bit, but I'm running into the same issue again. This is happening on prints that I've done many times without any problems, and using the same brand filament (Ultimaker silver PLA). It always seems to come down to the point in a print (usually about 1 to 2 hours in) where it's doing a lot of retractions - it just gets to the point where it chews right through the filament.

    I'm getting sick of throwing filament in the trash every time this happens, and wasting time printing partial prints that go in the trash too. I've tried modeling these parts differently to minimize retractions, but there's only so much I can do with it; they're complex parts. I've tried turning retraction off, which makes a huge mess on the print and gives me poor quality results.

    I'm hesitant to start monkeying around with temperature or print speed, because I've printed these items before at the same settings with no issues. What else should I be trying to fix this problem? Is there a maintenance issue I haven't checked? Should I continue to tighten the feeder wheel tension even further, or will this just make it worse?

    Filament.thumb.jpg.8ee244787a810c4aeabb8338aad8f86e.jpg

    Filament.thumb.jpg.8ee244787a810c4aeabb8338aad8f86e.jpg

  3. Ha, that was a pretty accurate video. I've had my Ultimaker 2 Extended for about 2 months now, and experienced some of the same issues. But going through the learning curve and figuring out how to model things to print well, along with getting my settings tuned in to what I'm printing, has led to some GREAT prints.

    I kind of disagree with him that it's not a beginner-level 3D printer. Maybe for cost reasons it might not appeal to hobby-level beginners, but as far as using the machine, I think it's been very easy. I didn't have any 3D printing experience before I got it, and had heard all kinds of horror stories about how difficult it would be. But it's been a very good machine.

    • Like 1
  4. I run across issues like this on a regular basis, as I'm trying to produce scaled parts where I have no choice on the width. The under-extrusion in your lettering could be fixed by slowing down the print speed and disabling retraction. You might have more to clean up afterwards without retraction on, but it should extrude better.

  5. When it comes to temp I print at 215 degrees with the bed at 100. But that is just the numbers on my machine, what they are in reality? Somewhere close in that area I guess but probably not exactly that temp. From what I understand UM machines also has a variation from "set temp" and "actual temp".

    Just for posterity, the UM2-Extended does have the ability to monitor actual bed and nozzle temps in the menu for tuning the current print. When I go to adjust either of these temperatures, I can roll the knob up to my desired temp, and it will show the actual temperature rising to meet it (or falling, as the case may be). I've noticed that the bed temperature is very slow to come up compared to the nozzle temperature (which makes sense: more mass to heat). But it's actually a very handy tool that I've been using lately, fine-tuning the temperatures during a print and watching how it affects the extrusion.

    FWIW, I can also adjust fan speed, material flow, print speed, and other settings on the fly. I'm not sure if this is common for other machines or not, but it really makes it easy to experiment with different settings and instantaneously see the results, without having to start another print.

  6. Hmm, I didn't have any problems with clogs. I had manually adjusted nozzle temp to 235C, and bed temp to 115C while it was preparing to print. It stayed there for more than 5 minutes with the nozzle hot, and never would print because it couldn't get the bed up to temp. It was actually starting to puff smoke out of the nozzle from the HIPS burning in there. Only after I brought the bed temp setting down to 100C did it start printing. But it didn't clog the nozzle.

    I tried several prints, all of which I had to abort due to the silly thing getting knocked off the bed from lack of adhesion. Even with glue and a big brim, it wouldn't stick. Only thing I haven't tried yet is blue tape.

    Anyway, I did end up manually tuning several things during the print. I brought the nozzle temp up to 245C in the hopes that it would help the layers bond better. Despite what I've read elsewhere, I have found that HIPS is actually pretty weak stuff because the layers don't bond too well. I can snap my prints much more easily than PLA due to this weak inter-layer bond. I was hoping that increasing the temperature and lowering my fan speed would help, but it didn't. You may be right that turning the fans off completely would be the best route. As well as enclosing the cabinet.

    But to be honest, if I wanted to go to all this trouble, I'd just print ABS. I'm not seeing any advantage to HIPS here. I was under the impression that it was as easy to print as PLA (just using higher temps), but had the strength advantages of ABS. Both those claims seem to erroneous in my case. And the fact that it stunk up the entire office (other people started complaining about the melted plastic smell) means that I'm pretty much done with it.

  7. I'm curious about this as well. I used up the first spool of silver PLA that came with my Ultimaker 2 Extended, and I need more (I'm on a deadline here at work). But their US supplier is out of stock on the silver filament.

    I had purchased 5 other spools of various PLA colors that were made by Prototype Supply. They are terrible compared to the Ultimaker PLA filament. I've had lots of problems with the Prototype Supply filament, the worst of which is that the extruder drive wheel chews threw the filament on a regular basis, which it didn't do with the Ultimaker brand PLA. It's also very brittle, and the filament has actually cracked while being fed through the Bowden tube. It extrudes decently, but tends to string a lot more than the other. More post-processing. And lastly, the Prototype Supply filament colors are not that great. The filament looks like a good solid strong color, but when you print it comes out translucent and weakly-colored. I have to print thicker walls on my objects to get the color looking right. The exception is their black PLA - it's good stuff.

    I won't buy Prototype Supply PLA again. But I am looking for the community favorite PLA brand that will give me decent performance.

  8. OK, I've learned a couple of important lessons this morning.

    I did try to set the temperature in Cura, but it did not affect the settings when I tried to print. I had to manually tune the settings after it started printing. That's disappointing. (I was using Cura 15.06.03 - I should probably try it again with the old version.)

    Once I got the nozzle temperature up, HIPS extrudes very nicely. It does provide a smoother wall surface than I was getting with PLA. Unfortunately, as I learned the hard way, the heated bed on the UM2E will only go up to 100C, which is not quite hot enough to keep the bottom stuck to the build plate (it seems 110-115C is recommended). My first print got knocked over pretty quickly after the fans turned on, because it warped the bottom of my print. It made a nice crackling noise as it curled up from the plate.

    So apparently HIPS does have some warping issues. Maybe not as bad as ABS, but certainly much worse than PLA. I never had problems with this print when using PLA. I guess I'll have to experiment with tape, glue, etc., to see if I can make HIPS prints stick to the bed when it only goes up to 100C.

    Last lesson learned is that yes, the fumes coming off this material are not pleasant. I was leaning in front of the machine, watching the extrusion process, and after a few minutes my eyes were burning. I'm starting to get a headache, too.

  9. I appreciate the input, and since my machine has only one nozzle, it would be printing HIPS the whole time, not sitting idle with HIPS in the hot nozzle. I don't intend to use it as a support structure, but as the structure itself.

    I chose HIPS to experiment with because I have read that it gives a smoother edge and is actually pretty easy to work with, in terms of not being prone to issues like ABS, etc. Supposedly, it has strength closer to ABS but without the warping issues, and without the fragility of PLA. Since I have a spool of HIPS, I at least want to try it out.

    Anyway, my question wasn't whether I should use HIPS. My question was how to set the temperatures for it at the hot end and the heated bed. Since my UM2-Extended only has factory defaults for PLA, ABS, and UPET, how do I tell the machine that I'm loading HIPS?

    When I go to the "change material" menu and it heats up the nozzle to remove the PLA, then I load HIPS, the nozzle won't be hot enough to even allow it to push the material through. I do see an option for "customize", as well as an option to import a material from the SD card. But I don't know how or what file type the material settings are stored, if I wanted to create a custom material.

    So basically my question is this: Should I just use the "customize" setting on the machine to set the temperatures I need for printing HIPS, or should I leave that alone and use the material settings in Cura to dictate the nozzle/bed temps? Does one override the other?

  10. Is it just a color variation, or a variation in thickness (width) of those layers?  Hard to tell from the photo.

    Have you checked the actual diameter of your filament at several locations to see if it's fairly uniform?  This could be a simple variation in extrusion due to filament tolerance.

  11. Nothing fancy compared to what some of you are doing, but these are some models I have been printing out for my company.  These are 1:12 scale models of shoring scaffold towers and formwork deck panels.  We are in the construction business, and are using these models for training.

    All the pieces are PLA, glued together, except for the wooden tops which are cut from strips of balsa wood to simulate real plywood.  One of these days I'd like to experiment with the "laywood" or other simulated-wood filaments for printing models of plywood sheets, but for now, balsa does the job.  

    Tables05.thumb.JPG.0723a203cdf9e4d9280e3ed273ae2a84.JPG Tables03.thumb.JPG.7cb2bba2bdbf86cf576588d43c17c5cc.JPG Tables01.thumb.JPG.ca6d40e0328baa734a8eb5bb8167f9db.JPG

    Tables05.thumb.JPG.0723a203cdf9e4d9280e3ed273ae2a84.JPG

    Tables03.thumb.JPG.7cb2bba2bdbf86cf576588d43c17c5cc.JPG

    Tables01.thumb.JPG.ca6d40e0328baa734a8eb5bb8167f9db.JPG

    • Like 5
  12. I have been using my Ultimaker 2 Extended for a couple of months now, printing only with PLA, and I'm not overly knowledgeable on using custom materials or settings.  I just use the settings that are in the machine by choosing PLA as the material when I load the filament.

    I purchased a spool of HIPS that I want to try out, but I'm uncertain how I tell the machine what temperature to set on the extruder and heated bed.  There isn't a HIPS option when I load the material.  From what I read, the older machines would control this through Cura but the UM2 series is controlled by the firmware.  Is there a firmware update that has additional material options?  Or is there a process for adding new material settings/options into the firmware?

    Or, is this something I set in Cura when I'm doing my slicing operation (I just downloaded Cura 15.06.03), and it will override the default PLA settings?  If so, do I just choose PLA on the machine when I load the HIPS filament, and hope that the Gcode settings from Cura will do the trick?

    Sorry if the question seems overly newbie-ish.  This is all very confusing to a new user, and the documentation doesn't do much in the way of explaining how to do anything beyond the basics.

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