productdesign

Hmm. well my point on Volume throughput is it would be good for cura to calculate this and reflect it in an analog dial with amber and red line. I noticed it does flash yellow and red if you go high on settings but those I was using did not flag either. I have stated on the thread illuminati gave, that this could be update related. I did not used to get this issue. Many folks saying UM2 used to not skip. and does now. On removing the drive case its clear there are areas rubbing, which is bad design. leading to people discovering over tightenin the case or loosening had an impact here. the concept of applying tension on that load wheel can only increase the offset in x-y and increase rubbing if you look through the thing its all very tight. If I may throw this back at Ultimaker, as mine is under warranty. Lets get away from user generated problems and slicer impact. Just using standard UM filament and a UM2 with the latest firmware, on changing filament this generates the skips. When you use the auto feed / change material as the material starts to flow from the nozzle. I suggest those who need to fix this, use that as datum. what ever the vol UM is set to push through on reload, is this expected to cause skips? would seem odd if that were the case. Im looking for a review of the firmwares involvement in this issue, who do I need to speak with, dya reckon? Cheers Chris

HI Folks just read all 5 pages of this thread illuminati pointed me to. The assessment is Im getting extruder skips. I see folks tweaking their Bits :oops: ..tpfe parts and discussing spool to feed radius and wd40 the bowden.. Thing is did it occur to anyone this was post update. I never had these issues before the recent cura and marlin updates. I also notice a slight flickering of the LEDs when in use. Could it be something is steeling power from the motor. or what ever reason induces a skip in the drive motor. I say its bad on UM if the motors are skipping at all. Lets leave it with the knurl wheel grinding as the limiter know we have mechanical slip/ grinding and or skipping. IS it Daid, who does this new firmware? Surely a trend could be easy to see by UM, Sander - Comments? Certainly interested to know what generates a skip in the system and how this could be tweaked out. I am reluctant to have to mess with code, UM should do this out of the box imho, as this seems a step back from UM1. Keen to get a fix so I don't have to build at a snails pace. :shock:

Cheers illuminati, That would make sense. I am only building at .25 to speed up the build. but working against me. What your saying is it can build quicker using smaller layers at higher speed then? Completely get the max volume throughput issue but seems odd the UM ships with 210 for PLA if we have to go over 230 to get a .25 build. why did they pull temp from the Cura UI? So is the skipping intentional as a fail safe , I assume not if some folks get it and not others. if its not intentional, are you saying its the motor bugging out on load? if the throughput vol is so intrinsically linked with build quality why does cura not show this as a quick calc. Just like the rev counter in ur car. you could see when your getting close to the red line. an analog dial would be good. as Im not going to have a clue otherwise. I know Cura does show red if your maxing it out. but there is a subtle difference in my suggestion.

Thanks for reply. speed in cura was default : 85 mm/s a part at .25 layer .with 24% fill density. The part was bad before any tweaks and not really helped by any tweaking of anything. The knock sound sounds like a grandfather clock. defo coming from the drive. I assume this is not retraction but on the knocking sound the grub counter clock rotates 45 degrees. I think i can determine a difference between intended retraction. Just disassembled the drive again and will put on some marker as you say. 95% certain this is the case. Problem being if this knurled wheel IS slipping on the motor shaft and I have max torqued the grub what else should i do to ensure no slippage. might have been a better Idea for Ultimaker to have keyed the end of the shaft rather than rely on mild steel grub. :???:

HI All, I have not used the UM2 all that much since we got it. although it seems to have performed ok. not sure if its update / firmware related or cura related but part has really sparse layers. I upped flow and temp to PLA 230c. and reduced speed to %70. Build still came out patchy and weak. I noticed a clicking sound coming from the extrusion drive while it was building. Was watching the knurled wheel and it almost seemed as tho the grub screw collar at end of knurled wheel was slipping on the shaft. Annoyingly you have to remove the whole assembly and have the motor fall off the inside wall just to tighten that little grub. Tightened the grub and removed material > refed material and noticed that it was still slipping under load new material. Is this possible as its very hard to see with the naked eye. Also wasnt sure if UM2 has a built in load sensor or something that could make the extruder back off and auto slip? I tightend the grub to the point where the grub stripped one time! Any thoughts from the group as my prints on UM1 were way better. Chris

Thanks for the input. I have done all printing so far with the usb. so i dont save out the Gcode. This was printed with a 1mm wall and zero infill. Creating a hollow part. The banding does actually occur in other places but it also occurs at letter ends. I cant see it in the layer view. I already use Cura. which is great. I have no idea what Joris is, but i dont think its been switched on. Re tolerating banding. I dont think Im being fussy. I just see prints, like those on Iluminartis page and or the Ultimaker promo pics and they look brilliant. I think its reasonable of me to want the my unit made and calibrated by Ultimaker for £1500 to be the best it can be with some tweaking. This is part of the issue isnt it, understanding what is normal and whats not. If it helps any the banding is worse on the run i did at 0.1 and better on the print at 0.15mm. Looking at the part side on. The banding does look like that layer has shifted as for every negative band on one side I get a posetive band on the other. Max 0.8mm shift I would estimate.

Thanks for the reply. will try taking a look at the ringing. what's surprising is just how many ghosts or rings were produced. I suspected this was a harmonics thing, especially as i think i ran one of them at about 60 print speed. I could imagine the bowden being a spring could introduce a harmonic. But you think the harmonic is in the bed? I would have thought it was a harmonic in the print head under the rubberised belts. Not sure how I could damp that other than use reinforced belts and maybe look at the bowden. Could attach a weight to the top of the bowden for example. will first try your accel setting. The ringing is probably less of a mystery than the random horizontal banding, what causes this? Has the bed shifted during the climb? I spotted similar posts where the z screw has been mentioned. mine has a slight wobble and if i handle the bed the whole thing does have some play. I cant see a way to remove that play however. Regarding the wobbly pulleys. you can hear from the whirring sound in the vid that you have inconsistent resistance in that axis. Eric De Bruijn posted this on your troubleshoot page. Presumably because there its undesirable for accurate prints?

Banding and ghosting seen. Hope you guys can help. http://umforum.ultimaker.com/index.php?/gallery/image/919-banding/

Hey Guys, I didnt realize you had made these replies, so not sure why im not being notified by the system. Anyway. I appreciate the input. I have watched the nozzle like a hawk as it does its first layer and i defer to all of your experience with the technology. To my eye it still looks like under and over extrusion caused by the stress inside the bowden. But practically speaking it does prints well and therefore i must be wrong. Though I don't discount the bed being warped by perhaps 0.5mm. What im observing are areas where the nozzle almost squishes the last layer it put down in parts of the bed and then in other areas its like a smeer of material going down, to the extent the layer is translucent. This may all be a mute point however as I dont think my prints are being effected, but that splooge effect im talking about perhaps is what caused that slight bulge in the circle discussed above. For the record only mods made are belt tightners we put on thingyverse http://www.thingiverse.com/thing:118917 The short belts feel tight. But as discussed at the start I note one axis has eccentricity, see new vid This cant be good! The issue I have, is I dont want to take the Ultimaker appart , this was the reason we opted for pre-build and tested. I assume they could be poorly machined. As I didnt put the unit together, Im concerned about damaging other bits if I dis assemble. Looking at it now, pulling out an axel will leave other bits under stress from belt tension. Or is this ok ? I assume the procedure is wooden end caps off > grubs on pully loose >then slide out of one end of the cabinet. The only observable issue I have seen in printing our work, is like the bed is shifting in as it winds up the z. so the layers are not going directly ontop of each other, would i be right to call this horizontal banding? I ran two identical prints more or less back ( second on 0.1layer . First was 0.18 Layer ) to back and one had really bad banding well 1mm shift, which ruined the look of it. If I can dial this issue in, I think were good. Fingers crossed I have not had warping or parts lifting from bed. Infact I have been finding parts stick like ***t to a blanket! Hard work getting them off Be good to get some advice on the pulley and or the horizontal shifting issue /horiz banding.

I printed a 100mm circle and got this result http://umforum.ultimaker.com/index.php?/gallery/image/850-p1010135/ Not exactly true, and more material in places, what causes this? however its better at squares! i just printed an a 190x190x10mm square as you suggested and it built well. So doffing of hat ...even though you could physically see in parts of the bed more material was extruding. Overall in practice the print turned out well. So it must just be a bed issue. Actually did occur to me althogh i would be shocked if it were the case, that the bed could be warped. were talking pretty high tolerances in that first few layers. In practice thats not a prob then. I re printed the part in question at the start of the thread ( well the prob area of that part ) re printed with no changes other than i did have to retape and remove bed and altered the min cool time from 5 s to 7s as iluminarti suggested. the results are good. So I guess thats sorted! Thanks. Just leaving my eccentric pulley to sort out. Can i correct this without Fing everything else up? I didnt build this so its a rubiks cube to me in what order I would tackle that. http://umforum.ultimaker.com/index.php?/gallery/image/849-imag1845/ Cheers for your help Chris

@ GR5. I don't think I could photo the pulley so it would show. You need to watch it spin to see the eccentricity. you can certainly feel the increase in resistance to the print head on this one axis. Should these things be sorted by UM before shipping. do you think I should contact support regarding lack of QC?

Thanks for the leveling tips. I ran the leveling wizard in cura a few times. Prob every other day since I got the printer and will follow your tips with paper etc when I get the hang of things. However I am confident the bed leveling isnt what your seeing there. If you saw it operating you may understand better. I would say all 4 corners of the bed are level +/- 0.2mm. When you watch the nozzle, it seriously only extrudes in the areas you see have more material. this is not leveling in my opinion. Im new to the UM but am an engineer. Clearly the extruder apperatus is effected by the x/y coirdinates in physical space. After all the sleve that runs from the extrude motor changes shape with x/y. Anyone heard of this happening?

Okayyy that's quite a bit to take in thanks. Cura says PLA is around 210 on the tooltip. On the print were discussing it was 215. BTW I just ran this bed leveling part and noticed a problem i saw very first print. It looks like there are parts of the bed where there is under extrusion and conversely areas with over extrusion. this photo shows the amount its put down in the first minute or so. Is this a separate issue and how the hell do I fix it? not that impressed that I this was'nt sorted before shipping :???: http://umforum.ultimaker.com/index.php?/gallery/image/848-imag1844/

I am glad Im not alone in thinking thats not the best QC by Ultimaker then. Do you think the slightly warped long belt axle is a concern? will look for minimum layer time settings then. Also what temp is best for their stock PLA? thanks Chris

Re-posted by request.: Hi All. Were just a few prints in to using our new pre assembled machine. Love the machine, but not sure its set up that well. The reason we were happy to pay an extra £500 for the machine to be pre-built and calibrated was in the hope it would be the best it could be. the test prints that were on the bed when it arrived didn't look that true. see pic. I assume that the purpose of this part is to calibrate -seeing shapes wonky means its not calibrated hence I presume it shouldn't have passed QC ? see circle and hex ) So we tightened belts with wave parts. checked print head xy friction and noticed one of the axles seems eccentric and gives a slight intermittent increase in friction as it goes round eccentrically ( poss +/- 2mm out ) Dont know how to tackle that as it appears to be bourn out of the grub screw by the belt rack ( grub screw by design pushes you off centre ) As I dont know how to fix, we printed something last night which turned out ok for the most except for a poor patch see pic. see all images here http://umforum.ultimaker.com/index.php?/gallery/album/139-troubleshootng/ Not yet contacted support but wonder if anyone can help improve the quality and consistency of the prints. Cheers Chris

Same problem here too. It has to be said this is due to the quality of component used if a fan is screeching out of the box! Perhaps UM should be adding that grease if they aren't going to use better components.