Torgeir

I'll say. right you are... Take care. Good luck. Thanks. Torgeir.

Hi @smartavionics, Thanks for this information and the link to the fix. Regards Torgeir.

Hi Frank5300, When I looked at your sliced vase using the monitor in Cura 3.2.1., I can see small hole (triangles) rotating around your vase. If I used S3D, your vase look really nice.. Here is a picture: I downloaded the .stl file for this vase and sliced using cura 3.2.1 and there was no issues, it looked very nice. Maybe there is some setting in cura that is creating this problem. Anyway, good luck. Thanks Torgeir.

Hi Kirbs, Firmware is just the "program" installed into the Arduino board that is controlling your printer. You just switch on your printer and select from the menu "Maintenance" then go to "advanced menu", then roll down to speed setting and enter. If you roll down in here you will find speed setting and the various stepper motor current setting (X,Y,Z & EXR1 (+EXTR2 not in use)). Here the current can be adjusted, but do not rice this setting if it is correct -as to high setting here can ruin your main electronic board. Often when stepper motors fail, it is due to high friction internally when the motor is at working temperature, rising current will create more heat in the motor and also increase the temperature on your controlling PCB (the expensive main electronic board). Thanks. Torgeir

Hi Kirbs, Just another possible issue here, did you check the stepper motor current? To lo current can create missed step if there is some friction involved. Have a look at the firmware setting on the printer setup menu, think it is under speed settings.. If my memory serve well, the current setting should be around ~1250 mA for those kind stepper motors. Just a thought. Good luck. Torgeir

Hi mayo77, Good info and well done. Thanks Regards Torgeir

Hi mayo77, Yes you're right. This is belt offset sound. It may happen on each of the 4 pulleys for the X axis or each of the four pulleys for the Y axes! Here it will sound loudly when the slider holding the 6 mm shaft is approaching an offset pulley. If the shaft is in the middle it does not make much noise, but will when coming close to the pulley. Since your printer have this sound all the time, it may come from an offset of the short belts, either X or Y. Noise from here will be present all the time, if it is offset. Belts (all six) used for a long time will wear and make noise due to the wear (it climb on the teeth), maybe a belt change is to be performed? The pulley teeth will be black due to rubber remains in here. Just some suggestions. It all depend of the total printing hour for your printer, however I'm not that heavy user, so I do not have any max. hour for belt replacement. But overdue belts will make noise! Thanks. Good luck. Torgeir.

Hi russlang, I'll think this sound is from both short belts, but mostly from the R/H stepper (the X axis). It should be possible to hear this sound when moving the extruder manually from right left (X axis), or in and out (Y axis), in order to confirm that this sound is due to a climbing belt. The belt will worn on one side and sometimes you find black rubber remains under the actual pulley that the belt is climbing on. PS. When cleaning inside the printer, it is a good practice to check the four corners for rubber particle's build up.. Thanks Torgeir

Hi Andy, This is very good improvement.. Torgeir.

Hi hoegge, You'll need to use the "windows mouse standard"; push wheel button, then you can move the whole model up and down to fit your view. Thanks Torgeir

Hi nallath, As always, you are right. Just checked my computer about yesterday and just found out that there was a silent upgrade running in background creating this influence on Cura. Very sorry for this! Startup time for Cura 3.1 is only 23 second. Torgeir.

Hi Folks, Just checked my computer about yesterday (18 of January) and just found out that there was a silent upgrade running in background creating this influence on Cura. So all of the below writing is not a correct observation. Apology everyone. Torgeir ------------------------------------- Hi Folks, Today I learned something new about Cura. If you last had a "big" model sliced with Cura, do not quit Cura after such a model, just save your big model, the open a simple gcode model and now you can quit. Re opening after opening a small model will open Cura kind of "fast". There is something related to the size of the last model that is delaying the startup of Cura. If you have several versions of Cura you're using, -say from 2.5 Beta and up, all of them is using same start "script" and is affected this way. Actually, the older versions may hang all the time, but after this "treatment" with latest Cura version, they all come to live again.. Well, maybe not a big thing but help me some.. Thanks Torgeir.

Hi Folks, This is a very detailed print with some issues. I'll guess this is the engine part of some "future space station"? I've also had a look into this model in Cura 3.1 and in S3D 4.0.1 and here is the pictures: Here we see the retractions that is visible very much in Cura. This is S3D with same part of the model, but a little wider. The colors represent print speed at details. Again, S3D, this picture show a "cutout" of the print at an interesting place, (color) of the speed information during printing at this layer. Well, just wondering if there is some head (extruder) play and a hit so the Y stepper loose steps? Or could the X/Y stepper current happen to be set to too lo current? You could say this is one of the reason why I alternate between those two slicers.. Anyway, just a thought. Thanks. 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.