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umagi

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Posts posted by umagi

  1. Contact the supplier, report the problem and you may well find they will replace the reel as it is faulty there may be more than one ocurance in the reel.

    Good luck

     

    That's what I did, and the supplier sent me a new one, from another batch. They indeed asked me for a picture of the fabrication label (including the batch ID) to send to the manufacturer probably.

    Nevertheless, any good manufacturer (the package in which this spool comes states "premium quality material") would have caught such gross fabrication error immediately, since this can be easily automated.

    • Like 1
  2. Found a 2.83mm section somewhere along my 1.75mm diameter filament spool...

    Doctor, would that be a problem?

    https://ultimaker.com/en/community/20351-damn-filament-vendor-175mm-filament-roll-has-283mm-fused-section-in-it

    It would be nice to have a setup that checks every new spool by automatically unwinding it and onto a second, empty spool while having the diameter checked somehow, since apparently this particular manufacturer does not seem to bother.

  3. What a nasty surprise I got when by accident, I checked my filament after my extrusion halted to a stop, with the filament ground (grinded?) into the profile of my drive nut...

    Somewhere along the roll, I discovered something that looks like a section that was fused together,

    or more probably it is just an extrusion fabrication error. In any case, that section has a diameter of 2.83mm, more than 1mm off the size it should be! Quality control please?

    5a331a79982fc_Filamentfuseerror.thumb.JPG.0c1296ae2be371dda189a4c2e9b20515.JPG

    5a331a79d9974_Filamentfusemeasurement.thumb.JPG.6409982965d07d5b269858de450e9efa.JPG

    spool.thumb.JPG.5843b27862073a735a5b3a258242a3e5.JPG

    For the remainder, this filament produced by Esun is rated to be 1.75mm is actually closer to 1.65mm.

    5a331a7a237c8_Filamentmeasurement.thumb.JPG.2d58814db4a7ebbb04c81250eac6ab00.JPG

    5a331a7a74167_filamentlabel.thumb.JPG.cb1cbbd6c45648da5ee6b33b2b8a37ab.JPG

    What else am I to expect of this spool?

    That they would sell such is thing is really scandalous.

    5a331a79982fc_Filamentfuseerror.thumb.JPG.0c1296ae2be371dda189a4c2e9b20515.JPG

    5a331a79d9974_Filamentfusemeasurement.thumb.JPG.6409982965d07d5b269858de450e9efa.JPG

    spool.thumb.JPG.5843b27862073a735a5b3a258242a3e5.JPG

    5a331a7a237c8_Filamentmeasurement.thumb.JPG.2d58814db4a7ebbb04c81250eac6ab00.JPG

    5a331a7a74167_filamentlabel.thumb.JPG.cb1cbbd6c45648da5ee6b33b2b8a37ab.JPG

  4. Hi swordriff,

    It is obvious that I am a beginner isn't it? ^^.

     

    A car is just a box with an engine and 4 wheels. How can they justify the difference in price between a KIA and a BMW.

     

    Well the difference is that we are talking about raw materials here, the result of a simple (but what do I know, I always hated my chemistry classes)  polymerization process to give a single, base material (well, if you don't count the carbon and fluor of course).

    What you are talking about are complex finished products.

    I agree that dimensional tolerances etc... can be different for a worked piece of PTFE, but I don't see how much different the raw material can be, which is the result of an automatic chaining process of the C2F4 monomers. Impurities maybe? Small impurities can have a great effect on material properties of course, cfr. semiconductor doping for instance.

    In any case, I was just wondering. As you suggested, I'll have to indeed experiment!

    Thanks for your valuable info.

  5. The Teflon from 3dSolex is 5-10 times more expensive (raw material) and is made in the USA compared to Teflon from China which is made in... China!

     

    Hmm... PTFE is just a polymer of fluor and carbon ... not sure any difference in polymerization process justifies a 5 to 10 times increase in price...

    As for TFT, I can't seem to find any info on that? What does it stand for?

  6. Hi Dim3nsioneer,

     

    Can you please tell us what PTFE coupler you are talking about? There is no 1.75mm PTFE coupler from Ultimaker

     

    You're right. I was looking at a well-known Chinese site...

     

    the TFT coupler from 3dSolex should have a similar bore/opening as the 2.85mm version.

     

    Yes, but have you seen the price ? 16 Euros for this thing? They must be kidding?

    Apparently, they are out of stock, "waiting from material from the US", so are they making these parts themselves? If so, I could try to make my own part, since I can have access to a lathe. However, I'm not sure how well PTFE is worked on like that.

    Update: I found this Youtube link that shows some (big) PTFE seal being made from a lathe, so I may give it a try myself, if I can find some PTFE rod somewhere...

     

  7. Hi.

    I'm using 1.75mm filaments with 4mm outer diameter bowden tube and noticed that the PTFE isolator in the printhead has an input diameter of 8mm!

    The exit diameter is 2mm, which is OK.

    Looking at the drawings of the vendors of such isolators, they all seem to be the same 8mm input diameter for the 1.75mm filament version, while the 3mm filament version has an input diameter of about 6mm, which is about right for a 6mm outer diameter, 4mm inner diameter bowden tube that is usually used for 3mm filaments.

    Since the bowden tube usually used for 1.75 mm filaments has a 4mm outer diameter (2mm inner), I really don't understand why the 1.75mm version of the PTFE isolator has an input diameter of 8mm!??

    Since I use a 4mm OD bowden tube, I have initially fitted the end of it with a 6mm OD section which I happened to also have. However, this is still does not match the 8mm input diameter of the PTFE isolator, and therefore results in problems, e.g. when inserting new material, since the hole of the bowden tube and the 2mm hole of the PTFE isolator do not normally align even when I use the 6mm OD section.

    I cannot imagine that I must use an 8mm OD, 6mm ID bowden tube for my 1.75mm filament... Or that I must fit a section of 8mm tube to my 6mm tube end for my 4mm tube (like russian dolls).

    Any ideas as to why such a travesty in the PTFE isolator design for 1.75mm filaments?

  8. Hi.

    I finally started printing with my self-built UM2!

    Many thanks to Coen for helping me out with my Ulticontroller board problem. I reverted to using a power supply setup closer to the original UM2 setup. I no longer have voltage peaks on my Ulticontroller board that used to damage the U3 voltage level translator chip thereon.

    This being the first time ever for me to 3D print anything (I haven't tried printing on other printers before setting out to build my own...) the first prints did not go smoothly.

    I'm using a 1.75mm PLA silver filament rated for 190C to 220C with a 0.4mm nozzle and Cura 15.04.4 as slicer.

    My first print was a simple test object, a hollow square vertical column 25mm x 100mm.

    I changed the nozzle setting in Cura to 0.375mm, after my first attempt did not have fused shell walls.

    My latest print of that object seems to go the right direction (Temperature was set to 214C,

    no overrides of the settings on the machine - all 100%, except for the filament diameter set to 1.75mm):

    5a331a5185a21_DSC00825(Large).thumb.JPG.78e6bbdc1773e914a8c99d3cfb106bfa.JPG

    5a331a526fe3d_DSC00826(Large).thumb.JPG.89fdc553cc002091f2f9d98835582860.JPG

    5a331a5297851_DSC00827(Large).thumb.JPG.78324583e9bd6a59c1b1a6201abdbfac.JPG

    The settings for this print were as follows:

    settings1.thumb.jpg.697c73fbaef2e68c3e2e4e4178f0fe4f.jpg

    settings2.thumb.jpg.00e67acab528f3bc4f7bf266c4912a95.jpg

    settings3.thumb.jpg.84be9ec349ddaad42831020011cfb6b0.jpg

    However, I am faced with one constantly recurring problem: my bowden tube keeps popping out at both sides.This seems to happen mainly when printing the first layer(s). I try to keep the tube in place, but actually quite a lot of force is required, even when printing at these low speeds of 20mm/s.

    In order to somewhat remediate the problem at the print head side, I printed a simple clip that I mounted on the knurled screw on the printhead. The teeth on the screw head and a tight hole diameter help maintain the tube and its fitting ring in place. This solution is effective in most cases so far, but sometimes, even that is not enough to prevent the tube being lifted out of the head.

    5a331a5134592_DSC00821(Large).thumb.JPG.a818eb53d7ad142f2f7e52ecc8019503.JPG

    At the feeder side, the tube keeps popping out however. This seems to start at the pruning stage before the printing starts. I can push it back in, but I must maintain it (and sometimes also the other end at the printing head) with quite some force for the few first layers of my print, after which things seem to go better and I can release the tube.

    Even though I am not using the shoehorse clip that seems to be standard in the official UM2 build, I doubt that using such a clip would help, given the amount of force I need to apply to keep the tube in.

    5a331a515e182_DSC00823(Large).thumb.JPG.a6328a0ddaa22a03b0a069386dc70727.JPG

    How come things seems to go better after the first layer(s)?

    As shown in my settings above, I set all speed fields in Cura to the low value of 20mm/s, and even then, I have this problem.

    I tested my extruder operation using Pronterface to extrude 100mm with the bowden tube removed from the printhead, and almost exactly 100mm was extruded by the E motor.

    I use the following extruder driver nut:

    5a331a5302327_UT8jicLXaXXXXagOFbXU1.thumb.jpg.6677b9b6246f2b990d92489da38a6875.jpg

    I noticed that PTFE isolator in the printhead has an input hole diameter that is too wide for my bowden tube, which is for a 1.75mm filament, and I therefore fitted a short section of a wider bowden tube on it at that end. However, the fit is still not perfect as the PTFE isolator hole is still somewhat wider than even that thicker tube section. I don't know however if that is an issue?

    Any ideas?

    Thanks!!!

    5a331a5185a21_DSC00825(Large).thumb.JPG.78e6bbdc1773e914a8c99d3cfb106bfa.JPG

    5a331a526fe3d_DSC00826(Large).thumb.JPG.89fdc553cc002091f2f9d98835582860.JPG

    5a331a5297851_DSC00827(Large).thumb.JPG.78324583e9bd6a59c1b1a6201abdbfac.JPG

    settings1.thumb.jpg.697c73fbaef2e68c3e2e4e4178f0fe4f.jpg

    settings2.thumb.jpg.00e67acab528f3bc4f7bf266c4912a95.jpg

    settings3.thumb.jpg.84be9ec349ddaad42831020011cfb6b0.jpg

    5a331a5134592_DSC00821(Large).thumb.JPG.a818eb53d7ad142f2f7e52ecc8019503.JPG

    5a331a515e182_DSC00823(Large).thumb.JPG.a6328a0ddaa22a03b0a069386dc70727.JPG

    5a331a5302327_UT8jicLXaXXXXagOFbXU1.thumb.jpg.6677b9b6246f2b990d92489da38a6875.jpg

  9. Hi...

    I did some measurement with the scope, and found some problems indeed with my setup.

    As stated above, I use a self-sourced switched power supply and an external AC switch whilst leaving the PCB switch permanently ON. This may be the cause of my problem.

    When using this setup, the VREF1 and VREF2 measurements look as follows:

    CH1 (blue) is VREF1, CH2 (yellow) is VREF2.

    CH3 (green) is measured directly at the DC output of the supply.

    vref1_vref2_external_switch.thumb.jpg.40831e529936d78e7adef74d57bd1b43.jpg

    Thus, a spike of almost 1V appears on VREF1 and VREF2, and the timing seems to correspond with the time when the 24V rail becomes live (i.e. the relay K1 closes), one of the figures below.

    When I use the PCB switch instead, the spikes do not occur:

    vref1_vref2_pcb_switch.thumb.jpg.9b768caf10d37f372db0f7a6148b2a75.jpg

    The 24V rail comes live as follows:

    vref1_vref2_pcb_switch_extra24V.thumb.jpg.ce4302a7214f8581102afdddaa97e6db.jpg

    The 24V rail activation timing seem to correspond to the time when the spikes appear when I use the AC switch instead of the PCB switch.

    I'm not quite sure why this is happening (is power supply coming up too slowly?), but I will immediately change my configuration and eliminate this AC switch and only use the PCB switch (or use an external switch, but at the DC side this time). I will also try to source a power adapter closer to the "official" one.

    vref1_vref2_external_switch.thumb.jpg.40831e529936d78e7adef74d57bd1b43.jpg

    vref1_vref2_pcb_switch.thumb.jpg.9b768caf10d37f372db0f7a6148b2a75.jpg

    vref1_vref2_pcb_switch_extra24V.thumb.jpg.ce4302a7214f8581102afdddaa97e6db.jpg

  10. Cohen from the Ultimaker team has confirmed the chip is not connected as suggested by the datasheet, and that he will correct this in the new revision he is working on.

    Although the chip does bidirectional level translation, it apparently matters what you define as VREF1 and VREF2, since it matters what you connect the EN pin to. Texas Instruments' reply clearly states that the EN pin should be connected (via the 200kOhm resistor) to the HIGHER voltage reference. In the case of the Ulticontroller v2.1, this is the 5V pin, while now it is connected to the 3.3V pin.

    And although indeed this would not normally cause problems, the fact is that the U3 chip on the Ulticontroller should be wired differently.

    When I posted this message, I was just wondering if Patrick Olma may have been from Ultimaker, partly because of the timing of his inquiry and the timing of my first post on this forum about the schematic discrepancy for U3 with the datasheet, the similarity of his problem with mine, and partly because of his Dutch sounding name... Looking more closely at his post however, I should have realized that his design did not correspond to the Ulticontroller design... So, my assumption was wrong, and I apologize for this.

  11. Hi Cohen,

     

    I don't know any Patrick Olma, the question did not come from Ultimaker (weird coincidence timing wise though).

    Amazing coincidence indeed! Some would call this synchronicity....

    As to your request for more info about my setup, I attach the following pictures. Hopefully they will turn out clear enough:

    5a3319a2b40bd_UmagiDesign1.thumb.jpg.60f43f3fa61d86b20fc3936d96bcfb42.jpg

    5a3319999830b_UmagiDesign2.thumb.jpg.98016465d9bfe4eb6d4a298677ef4faf.jpg

    I like to refer to it as "full metal jacket", because I used aluminum everywhere (support frame from extruded alu 2020 and 2040 profiles, alu bottom plate and middle cover plate, alu shaft support plates, etc.). The cover panels themselves are composite alu ("Dibond"-like), 4mm thick. The control knob is massive alu as well, and I took the - late - precaution to insulate the rotary encoder's shaft with a thick insulating crimp sleeve, after my first Ulticontroller blew up.

    As mentioned earlier, I connected the ground lead from the AC mains to the alu bottom plate, near the AC power input connector. Also, I installed an external SPST switch (with built-in lamp) at the AC side to switch the system ON and OFF. This implies that I leave the power switch on the Ultimaker main board ALWAYS on the ON position... I don't know if this may be a problem or not.

    I tried two different SMPS supplies, first suspecting that the first one may have been of bad quality. The 2nd one though seemed to be of high quality but I also had the Ulticontroller failure with that one. However, I'm not experienced enough to determine the quality of a switched power supply...

    As to the grounding thing... this is still a shady area to me. I thought it was good practice to AC ground metal frames of machines and electronic equipment wherever possible. But maybe not when using supplies with floating DC outputs mounted the way I did? Should I put the PCBs in plastic casings instead of directly mounting them to the alu plate (main board) and alu frame (ulticontroller)?

    5a3319a2b40bd_UmagiDesign1.thumb.jpg.60f43f3fa61d86b20fc3936d96bcfb42.jpg

    5a3319999830b_UmagiDesign2.thumb.jpg.98016465d9bfe4eb6d4a298677ef4faf.jpg

    • Like 1
  12. On the TI site, I found that someone named Patrick Olma (someone from Ultimaker, I presume?) posted the following question:

    https://e2e.ti.com/...rface/f/390/t/495210

    Looking at the date, I also assume that his question was posted after I flagged it in this forum.

    This was the message:

     

    Patrick Olma, Mar 3, 2016 3:49 PM:

    Hello,

    We are using the device PCA9306 as i2c level shifter to communicate between a 3,3V Master and a 5V Slave. Both sides of the SCL and SDA Pins were pulled up to VREF1 / VREF2 by using 1,8k resistors.

    Unfortunately we mixed the VREF pins - so the 3,3V Master is connected to VREF2 and the 5V Slave is connected to VREF1.

    Most of the time the device as well as the i2c communication works well, but under some circumstances, the device gets damaged.

    Could the wrong connection of the VREF pins be the reason for this?

    Best Regards,

     

    The response from the TI employee is rather interesting:

     

    Response from Rajan Arora, TI Employee Mar 3, 2016 4:25 PM

    If VREF1 (5V) is larger than VREF2 (3.3V) then the VREF1 pin can be tied to the Enable pin, and pulled up to 5 V using 200kohm resistor. The EN pin should be tied to the larger voltage supply. Is this a possibility?

    You are seeing damages on the device in the configuration because the terminal voltages on the transistor are exceeding 5.5V which is the recommended max on the terminals. This can result in extra leakage current. Can you list under what circumstances you see the damage (high temperature)?

    So to summarize the damage is due to the incorrect connection. if possible I recommend changing the connection on the board to match the datasheet, or tie the EN pin to the VREF1 pin.

     

    I guess I will try to jumper EN to VREF1 then, if possible at all. I am expecting some clarification from Ultimaker though...

    • Like 1
  13. Hi Gr5,

    On the TI site, I found that someone named Patrick Olma (someone from Ultimaker, I presume?) posted the following question:

    https://e2e.ti.com/support/interface/etc_interface/f/390/t/495210

    Looking at the date, I also assume that his question was posted after I flagged it in this forum.

    This was the message:

    Patrick Olma, Mar 3, 2016 3:49 PM:

    Hello,

    We are using the device PCA9306 as i2c level shifter to communicate between a 3,3V Master and a 5V Slave. Both sides of the SCL and SDA Pins were pulled up to VREF1 / VREF2 by using 1,8k resistors.

    Unfortunately we mixed the VREF pins - so the 3,3V Master is connected to VREF2 and the 5V Slave is connected to VREF1.

    Most of the time the device as well as the i2c communication works well, but under some circumstances, the device gets damaged.

    Could the wrong connection of the VREF pins be the reason for this?

    Best Regards,

    The response from the TI employee is rather interesting:

    Response from Rajan Arora, TI Employee Mar 3, 2016 4:25 PM

    If VREF1 (5V) is larger than VREF2 (3.3V) then the VREF1 pin can be tied to the Enable pin, and pulled up to 5 V using 200kohm resistor. The EN pin should be tied to the larger voltage supply. Is this a possibility?

    You are seeing damages on the device in the configuration because the terminal voltages on the transistor are exceeding 5.5V which is the recommended max on the terminals. This can result in extra leakage current. Can you list under what circumstances you see the damage (high temperature)?

    So to summarize the damage is due to the incorrect connection. if possible I recommend changing the connection on the board to match the datasheet, or tie the EN pin to the VREF1 pin.

    I guess I will try to jumper EN to VREF1 then, if possible at all. I am expecting some clarification from Ultimaker though...

  14. Cohen,

    Also kindly notice that the NXP datasheet for their version of the chip states absolute maximum rating of 6V... Since those chips should be compatible, I wonder why NXP made their requirement more conservative...

    Furthermore, the NXP sheet says that for optimum performance, VREF1 should be less or equal to VREF2 minus 1 V... Again, why would they state that?

  15. Hi

    I don't know if this may be a problem or not, but I use an external SPST (single pole, single throw) switch at the AC side and I leave the switch on the PCB (i.e. DC side) always ON (I did this due to mounting and accessiblity problems in my build). The AC switch turns the Switched power supply on and off, of course.

    I am really at the end of my wits here, trying to figure out why my Ulticontroller keeps blowing up (chip U3).

    If the above is not a problem, may my problems be due to bad power supplies? If so, how can I check that?

    Any help is welcome as these problems are getting very frustrating...

    Thanks!

  16. Hi Cohen,

     

    Did you check your voltages with a multimeter?

    Yes, I did, and the voltages at the test points are as indicated in the schematic.

    As already mentioned, I replaced the chip, things worked for a while, then it blew again.

    I had no other choice but to buy a new board (a new set actually consisting of main board v2.1.4 and ulticontroller 2.1), but as I wrote in another post in this forum, that one blew too... Same U3 chip... same frying "hump" on its top.

    Since noone else seems to have that problem, it must be with my setup indeed, but I can't see what is wrong with it.

    I have a full aluminum extrusion build frame, with aluminum bottom plates. The whole frame is AC grounded.

    Mounted on theses plates are a switched power supply 24V/10A (also grounded) and the main PCB. The Ulticontroller is mounted on the extrusion frame.

    I don't know if this may be a problem or not, but I use an external SPST (single pole, single throw) switch at the AC side and I leave the switch on the PCB (i.e. DC side) always ON (I did this due to mounting and accessiblity problems in my build). What do you think?

    I build my machine in an environment where I regularly get static discharges. My control knob is full aluminum, but I insulated it from the rotary controller's shaft to eliminate that possible ESD path.

    Is my switched power supply bad? I tried two different ones (for the first board, and another one for the second board).

    Also, since the DC power output is floating, is it better to put the PCBs in their own plastic casings instead of mounting them on the aluminum panel and frame?

    Experts! Please help me out here...

  17. Changed to 16 steps for the Z by installing the jumper on JP3, and the "resonant" noise when the Z shaft moves up and down (homing and to Z=0) have basically gone.

    However, my Ulticontroller board has again failed, and again, it's the U3 chip that has blown with a very visible burnout hump on the chip.

    I really start to believe this Ulticontroller design is flawed big time!

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