Torgeir

You're absolutely right, good point.. Forgot that.

Adding pictures as above in here is sometimes a pain, as I'll often end up with a double set of pictures..

Strange, Just tried again.

Hi Folks, As I've been using S3D for a "long" time in order to study sliced models before printing, I found that Cura now have a good G-code viewer. However, the last version (Cura 3.1) do not have as good viewer as found in the beta version 2.5, as it sometimes add a small drop. In order to show the difference, I've added two picture of the same sliced model (Arthur's flow/speed test) first from S3D and Cura 2.5 Beta (none of them shows the Z stitch). I've also added a picture viewed with Cura 3.1 of the same sliced object. Here's the link to "Arthur's speed test"; https://www.youmagine.com/designs/test-print-for-ultimaker--2#activity S3D and Cura 2.5 Beta Those two are showing all details the same as far as I can see.. And Cura 3.1 (Note the extra drop just under 10 ... ) The little droplet just above the S (the upper) is an error in the existing Gcode file and shall be visible on the print. Thanks Torgeir.

Hi Andy, I've been investigated some over those ringing marks we often see on our prints, if the speed is set to high. -I've learned that this was due to flexing short belts. However, after some experimenting I found that the flexing mostly come from the extruder itself, and is caused by the weight and flexible attachment of the extruder assembly. Another contributor to this is the CT (center of gravity) of the extruder as it is located under the center of the gantry. When our printing object have details as writing letters or repetitive pattern the printer head (extruder) may be very close to resonance, even if the print speed is «relatively» slow. This ringing often propagating to the metal housing for the two fans and the tiny metal walls in here start making additional noise. Due to the spring effect in the gantry setup, the print head continues for a short while (muted oscillations) and appears as an echo in the print object as it disappears. In order to prevent this to happen we can reduce the print head weight, move the center of gravity up toward the center of the two 6 mm shafts and this will reduce the ringing (or say increasing the resonant frequency). However, if we increase the printing speed enough, the ringing problem will reappear. As I see you already have 6.5 mm belts installed on your printer, -my printer have only 6.0 mm GT2 belt, but can take 6.5 mm belt.. The printer head in the UMO seems to be much lighter than the one used in UM2, are you using hollow shafts? UM2 head weight complete is about 127 Gram, and the two 6 mm shafts (127 / 117.4) Gram. The four 8 mm shafts weight is; (2 X 131.4 / 2 X 135.9) Gram. Belts and pulleys approx. same as yours. Thanks Torgeir.

Hi, For what it's worth, Windows defender often try to remove some files from Cura 3.1 folder. This often occur during startup of Cura. So, is there any info replied to UM when we start this program? Here's my two path "default" (using Win 10). Thanks Torgeir.

Hi Andy, Thanks. Very busy for the time being, so reply will always take some time. Just come to think about what caused this small bubbles, -realized that this is the corner were the extruder head make a 180 turn -at speed. So this seems to be the reason for this remains at the corners.. Great way of doing it. K element (Chromel/Alumel) have been used for a very long time in the aviation, esp. for ITT/EGT temperatur monitoring and is still used here. Believe it or not, but today PT100 is used as an absolute temp sensor in modern jet/turbine engines. By the way, the PT100 is now available as a (-200 to 600) deg. Celsius version in Class A. Same thing happen (bubbly lines) were the little squared box made inside the lower part of the "U" profile of the wall. (Can only be seen on the Cura print). Only seen the half way up the wall. (Have a look into the sliced model using the monitor.) I'll do the same thing, but hawk eyes.. hmm not any more for me. I'm sure your printer will be as good as UMO should be, I've seen UMO prints looks as good as the UM2 can do, but need a little more "attention" over time. I'm still only using PLA, as it is predictable and very good for prototyping models etc. Later I'll need something that is stronger and not as brittle as PLA. Thanks Torgeir

Good idea about the benchmark testing, -as it will be allot easier to compare and share experiences. Thanks. Torgeir.

Right you are, it is actually a little thicker. Torgeir.

Hi Folks, Here is the difficult first level, just zoom in and see how close it is.. This is how much I'll squeeze it.. This is pure black filament, so you see how tiny the layer is.. After this way of squeezing, I've never have any prints lift off, but it is hard to get off. Just wait until it is cold. The calibration paper I'm using is the kind of receipt from the ATM.. Ops.. (Standard paper is 0.15 mm approx. and ATM paper 0,07 mm) Thanks. Torgeir.

Hi Lars86, Yes, I've been going the other way-, trying to decrease the weight and eventually the "moment of inertia" for the whole gantry (sure not easy, but fun, -because it is all about those small little details).. Thought about hollow, or gun drilled shafts and even thin walled straight stainless tubes. The latter one is interesting, as a 8 mm shaft with wall thickness of 0.25 mm (same length) will weight only 11.3 Gram! Seems unreal? Well, had two 8 mm shafts scrapped due to too much play. There's some smart things to do, -then we can use such shaft's in your UM's... So, what can we do??? Short 8 mm shaft weight; 131.4 Gram and length 337 mm. (I have a precision weight that's calibrated!) Long 8 mm shaft weight; 135.9 Gram and length 347 mm. I'll fully agree with you that it is the self resonant frequency of the extruder head is what cause "most" of the ringing in the print and NOT the short belt. Well, -as I do not have an UMO (the grand father of UM2) but an "UM2 ext", I'll believe this issue is valid for all UM's -more or less if the speed is set to high.. Hint; there is a wider belt to try! As I've never seen this test object Andy refer too, I just downloaded the square one (for resonance test) to see what this print would look's like. To be fair, I downloaded the new Cura ver. 3.1.0. Used all default values, and let it go in order to see what it could be. Also, I just recently got a mail from S3D about there was a new ver. 4 out to download for me. So, downloaded this one as well. Did a monitor view of the model and saw that the writhed text was very bad "melted and over extruded". So, deselected the retraction and print looked good. So I printed the object sliced by the two different slicers, Cura ver. 3.1.0 and Simplyfi3D ver. 4.0.1 The left one is S3D and right is Cura. Funny, but the one made with S3D is darker than the right done with Cura. Both is smooth, but S3D has better smoothness.. However, Cura's measuring is way better; 50.0 mm X 50.0 mm and 16.0 mm height (with 0.1 res perfect!) and finally wall thickness 1.0 mm same accuracy (amazing).. It's a little unfair over S3D as I did not do any correction for the line width etc. with S3d, but been using Cura as a standard for my print of course.. Some more details from the Cura printed object. The texture inside the box. See the small bubbles in the middle, oscillation.. Cura 4.0.1 Corner with bubbles. Cura 4.0.1 Same here, but otherwise very good.. Cura 4.0.1 Ps. All pictures is high res. so just zoom! Keep up the good works (with an Ultimaker). Thanks. Torgeir.

Hi Tor, Great, it is said to be different, but the difference is just +/- 0.8 deg. Celsius max. in the area (0-300) deg Celsius. There is "generally" two type of PT100 RTD's (resistance temperature detectors), type A and type B. Type A contain two resistors (each 100 ohm at 0 deg. Celsius) in the same capsule and have 4 wires. It is often more than ten times the price of type B! Type B only have one resistor and normally only 2 wires, however, if the sensor is located far from the measuring electronics it may have 3 wires or sometimes even 4! This additional wires is used to measure and compensate for the additional resistance in the wires. This can actually be done by the firmware as well, if the wire length is an issue, but in the UM2 PT100 wire length is just around 1 meter or so, so not that much of an issue here.. If one is worry about measuring as good as possible, you can use copper paste when installing the PT100 (this is good for the heater element as well). The copper paste is the "best" heat transfer compound for our temp area up to 300 deg. Celsius. This will fill up any air pocket between temp sensor / heater holes in the heat block. The benefit here:. 1) Much better average temperature control of the heath block. 2) Easy to remove and reinstall when needed ( but remember never re-bend the wires that is close to the sensor / heater, they are very easy to break and do not pull the wires. Push it out from the opening where the removed lock screw is located.) 3) Will protect for corrosion. When installing with copper paste, make sure that there is enough paste as we do not want any air pocket in here, as this can reduce the heat transfer. Wipe off the excess of paste with a cotton rag. Do not install the two cooling fan yet, we need to preheat the heat block and let all the excessive volatile additives to go out of the copper paste. So it will drip off, so be ready with the rag.. Before reaching the high end about 240 deg. C it will smoke just a little, so have ventilation when doing this. After this "burn in" process, the printer is ready for use. If your printer is some aged and the sensor and heater is fastened into the block, do not try to remove as it is very easy to damage the sensor / heater. This is to be added when you install a new PT100 sensor or a heater. As an example; I can do the speed test print at 207 deg. C. easily with my printer and my heat block temperature is very accurate and stable. Here is this test:. https://www.youmagine.com/designs/test-print-for-ultimaker--2 Well a little long winded, but just some gen info about this issue. Thanks Torgeir.

Hi jonatanrullman, This is an undefined error type related to the printer firmware, try to update you printers firmware. From the picture I see that this is an UM2 or UM2+. There is some report about about this problems, so have a look into this thread: https://community.ultimaker.com/topic/7968-error-stopped-heater-error/ You'll find your error type a bit down in this tread. Thanks Torgeir

Hi |Robert|, Sure agree with you here, -why I reacted on this value is simply because that over the years I've been replacing quite a number of PT100 (in the aviation) and all of them was found "open" I.E. measures infinitely high resistance, but ofc. a short may be possible as well. As the reading is quite close to the heater resistance, it's just makes me wonder because this is a brand new unit.. Happy New Year. Thanks Torgeir

Hi Tor, Sorry to break in here, but your measuring is kind of strange.. 12 Ohm is not right here, -but a bell is ringing.. This value is not very far from the expected resistance to be measure at the nozzle heater element wires. So try to measure the heater element and let us know this value. Kind of weird, but could those two wires have been swapped? The heater and the PT100? On the connector for the PT100 there should be two red wires connected to one pin and a transparent (or white) wire to the other pin? Sometimes there is only one red and one transparent on each pin at the nozzle temp sensor connector going to the main PCB (printed circuit board) Temp1 connector. As Robert said, there should be about 108 Ohm at room temperature from a PT100 sensor, so approx same resistance at the bed and nozzle sensor! Well, just my 2p.. Good luck. Thanks Torgeir

Hi Ghostfather, Welcome in here. Have a look at this link about your problem. Good luck. Thanks Torgeir

Hi Folks, Forgot to mention the benefits of using Copper Paste in this way. 1) Improving heat transfer in between the components in the heat block. 2) Prevent seizure of nozzle, heater, PT100 etc. 3) Also serve as a "secondary sealing" of nozzle and "cold junction nut" (the steel nut attached to the heath block and coupler). If you use Copper paste this way, be careful and prevent adding this paste into the nozzle or inside the heat block. Another interesting thing to note is that; the copper paste is the second best heat transfers compound commercially available. The best one is “Silver pasta grease”, however this one start to loose the thermal conductivity at around (120 – 150) deg. C. and Copper go to about 300 deg. C (Celsius). For seizure typically (1000-1100( deg. Celsius! The thermal conductivity difference between those two is less than 5%. Price more than 10 times. In the Ultimaker 2 assembly manual at page 50; it is stated that the copper paste grease is used here to prevent corrosion. But to me it looks like the heath transfer between the “cold junction nut” and the “cold block” (the radiator and the upper/lo aluminum squares), is a second reason for using Copper paste in here. Attached page 50 from the Ultimaker 2 assembly manual: Thanks Torgeir.

Hi kbtwining, Welcome into the Ultimaker Community. You made a very good description of your problem and it seems to be a known problem.. After reading through your post, we'll be very interested to know how is your PLA filament behaving after 3 years of storage? Does it become brittle and break off with a "snap"? This is typically for old PLA that's been attracting some humidity over time. What's happen is that the PLA tend to break inside the bowden tube, but still will be feed all the way through the tube and to the extruder. However; between the end of the bowden tube and the coupler (the white Teflon adapter you see inside the spring at the extruder), there is a little gap and at this place the filament tend to hook up preventing anymore feeding. So, do not change anything but just have a new fresh roll of new PLA and do another try. PLA have to be stored in a "controlled" environment; humidity as lo as possible, normally less than 17% humidity and in darkness. However, this is another topic.. PLA can be renewed to some level, -but again another topics. Good Luck. Thanks Torgeir.

Hi Folks, Congratulation with a new "home" Ultimaker! Much better Thanks. This topic about nozzles is interesting as this is one of the most important little detail of the printer.. As I'm using the original (25W) heater and PT100 sensor from the UM2 standard heath block on a OB with a 0.4mm nozzle. I noted some difference between the old and the new. The feeding speed was not that impressive. -So I used the copper grease on the nozzle thread in order to improve the heath transfer from the heath block to the nozzle. Also filled the two holes in the OB for the heater and the PT100 sensor. Then heated it up step by step, in order to clean off the volatile substances from the grease dripping of the block. Gradually increasing the temperature until 230 deg. Celsius. Also insulated the OB to avoid heath leak. After this treatment, the whole thing really improved much. I made a feeder test (the cylinder) and started printing at 205 deg. C. When the temp decreased 1 deg. C. during the printing, I increased the temp one more deg. C. At the very end of this print the heat block temp was 207 deg. Celsius. I'm using a standard UM2 feeder, belt geared 1:2, -but the BIG difference here is that I'm driving the filament on the inside of the looped filament. NOT on the outside of the filament as Ultimaker do it -and this little difference make a BIG reduction of the friction! All filaments with memorized roll up, -will improve feeding when feed from inside the filament loop. This mean to mirror the UM2 feeder and change rotation direction. Thanks. Torgeir

Hi Mike, Great and make sure that there is no short or suspected connection inside the new extruder unit, as this is very rare that it is just happen like that.. The new board looks right.. Good luck. Thanks Torgeir.

Hi Neotko, Long time no see.. Your observation is sure correct, the diodes decrease the power to the stepper coils (the heat created on the diode pack). So there is always a kind of "drawback" when we make correction for single issues. There is a third - way to overcome such a problem we see in this setup, if we want to have the best result here.. This is to move the drivers as close as possible to the steppers in order to avoid such a high "harmonic ringing" in the stepper feeder wires. However, the driver have to be separated from the stepper to avoid the heath from the stepper motor. (This is not very easy to do on the UM2 versions.) The long feeder wires, especially on the extended versions, create additional inductance to the whole circuit and make this problem worse. Edit: To relocate the drivers increase complexity and ofc. the price, but there is room and possibility on an Ultimaker for sure.. I was thinking of moving the mother board high up on the back side of the printer (an ext ver) in order to decrease the feeder length, but never did. Hmm. Maybe I'll try this, but later on.. Anyway, very interesting topic, keep up the good work. Regards Torgeir.

Ops. forgot to mention that the 5V regulator is U6 and the type is: A4403GEUTR-T. Torgeir.

Hi Mike, Just some toughs, since your computer have been working for quite some time, I'll suggest there might be a faulty wiring inside your new extruder as the hot end cooling fan is directly wired to +5VDC without any fuse. Maybe there is a short all the time and the protection circuit would not turn on because of a constant short. So, try to unplug the 5 V fan (J34) and try to power the printer up.. Anyway, we have the full wiring for this card (V2.1.1) and I'm using the same one as you. Here is a direct link to this PCB. https://github.com/Ultimaker/Ultimaker2/blob/master/1091_Main_board_v2.1.1_(x1)/Main%20Board%20V2.1.1.pdf Good luck. Thanks Torgeir

Hi Mike, Check TP76 or TP77, this is the VCC/2 voltage that should be switched 24 VDC and present when the printer on/off switch is on. Edit. If this voltage is present, your 5VDC regulator might be faulty. If there is no voltage present at those test points, your printer on/off switch might be faulty. Good luck. Thanks. Torgeir.

Hi Zeki, Just been looking into your posting here and noticed you've got lots of good advices here. As I've got a «similar» printer as you have, I'll have noticed a few issues to comment. But first, the feeder stepper motors used in UM2 and UM2+ is different and the main difference is the number of steps per rev (360 deg.). UM2 use a 400 step/rev. stepper motor and UM2+ use a 200 step/rev. stepper motor. If the filament have heavy marks (dented), then, how much tension is your feeder set to? Normally it should be between the lo pressure mark and half mark setting (the middle is about max I'm using). The tension indicator is located on the right side of your feeder unit, locking into shaft (the old type). The upper position of the mark, is the lo tension, turning the umbraco (hex) screw counterclockwise increase pressure.. Heavy markings, takes a lot of the torque from the stepper motor.. As you now manage to have the heath bed properly adjusted, actually very close to the bed, this will increase the feeder pressure somehow, especially when making the initial layer. So for an UM2, reduce the speed for the initial layer to 15 mm/sec. This will reduce the torque your feeder have to cope with and should helps a lot here. Another thing to mention, is the temperature for the nozzle when using PLA, -well «normally» I'll never go higher than 204 Degrees Celsius. My best prints is usually done at about 186 deg. C. and at 30 mm/s print speed. Assuming you bought this printer second hand(?), -so if nothing can improve, you might consider go for a full upgrade kit to have an UM2+.. Will almost be as a brand new printer. Edit: Just wrote this, when I'm saw you mail just arrived.. This could just be some remains partly blocking your nozzle, or a squezed coupler (the insulator block) on top of the extruder block. For the nozzle to clear, try the “atomic-metod” and see if this clear the nozzle you might do it several times.. Here is how: https://ultimaker.com/en/resources/19510-how-to-apply-atomic-method It is very important to follow this methode as it is described! The coupler have to be replaced. Anyway, good luck. Thanks. Torgeir