Torgeir

Hi Folks, As we now can see that the additional force needed to overcome friction in the bowden tube can be an issue in order to have enough pressure to assure proper extrusion, lets see how this thing can influence our print object. If we study the movement of the extruderer when moving at different places on the bed, you might see that the feeder inside the bowden tube twist a little when moving around the bed. The worst twist difference occur from right inner corner to left outer corner, or the other way around. This mean that the feeder track go offset from the top of the bowden tube, due to this the friction factor go a little down, so now the effective pressure at the feeder increase – so we will have more filament extruded out of the nozzle. So, we now actually realize that the feeder pressure might vary at different places on the heat bed. This is not very visible when the extruder moves around all the times, but will be obvious when the extruder work for some time at a details on a large print object at different places. If we assume the “worst” case, thinking that this movement can create under extrusion, but probably more often seems like -just before under extrusion or some opening in lines.. Then to the issue when we try to extrude more than the printer can do. In this case we’ll compress the feeder inside the bowden tube (yes it’s really work as a compressed spring), if we try to rice the temperature the printing improve some, but it’s not good. In this situation, when trying to adjust in order to improve – any normal “small” adjustment do nothing. Retraction do not work very well and suddenly the extrusion stop. (Actually in this above case, we might not know that the printer is reduced by high friction force when we try to setup for a default speed.) Yes, I know there is many things that can be the reason for this scenery, but here we look at the feeder working against friction forces and what “can” happen due to this. You know, the filament for a 3D printer is like the petrol for a car! What is interesting here to see is that feeder friction can lead to problem that put the focus away from this issue, because so many other thing occur due to this one issue. Thanks. Torgeir.

Hi, Yes, forgot that you're using the 35 W version. Well, I'm using the OB and 25W heater element and no problem at all. But I'll guess it will depend of what kind of material to be used etc. Good Luck. Torgeir.

Hi neotko, Yes, I've been reading your posting about this issue with interest and compared it with the "MK8 experiment" i did sometimes ago. I’ve had to do the "reverse" engineering on the requested number of e-step for the UM2 in order to find this "theoretical diameter". So the effective diameter for the 8 mm knurled feeder wheel found using this approach appear to be approx. 7.2 mm(?). I'll think you are right in that the feeder is compressed and build/accumulate up pressure by making a sort of S pattern inside the bowden tube. Torgeir. (Right now down Sout in Spain. )

Hi rigs, This is great info, thanks. Regards Torgeir.

Hi Folks, This issue is something that is never been taken to the very end and solved! Searching this problem in here do not help very much, but when Google from the outside, you get inside! (Here.) So you could say I've been seeing lots of people addressing this problem, -but been "stopped" by some comment that should never been said/asked! I have to say, I'm very sorry for that! OK., I've made a simple drawing of the setup with this issue, just something to start some discussion if you want. Yes, this is about how friction can work and make problems. Friction is a coefficient that is "more or less" constant for a given material and can never be higher than 1, or less than 0. What is the problem then, -it is the force that is needed to overcome the friction! Now we can start the discussion. The issue is that; the track after the feeder wheel is following the outside arc of the bowden tube and will create more friction than the clean filament. As the pressure from the feeder is directed into an "180 degrees" bowden tube, we will have a situation like this: PS. Borrowed the picture from here: http://www.fabbaloo.com/blog/2016/1/31/bowden-style-3d-printings-critical-element-the-tube To help a little here, we have some very good tools; Solid Works and Fusion 360. Here you can do the calculation of the friction and you'll see some pretty interesting numbers! I do not think much more is needed in here? Ok. You're next. Thanks. Torgeir.

Hi, The middle screw hold both, the heater element and the PT100B thermistor. Be careful and not rebend the wire when removing the PT100B, if needed. Just buy one heater as a spare, this is the one that's work the hardest. But they also can last "almost" forever.. PS. Robotdigg sell each of them for 6 USD.. But takes a little bit longer to get. The heater should last a lot longer than this. Thanks. Torgeir.

Forgot to answer your last question. The stepper motors will use some higher current during microstepping (the silent step is not so silent anymore), but this is way less than full step current, so no worries here. Torgeir.

Hi cloakfiend, The metal wire is actually two cords (each having a diameter of 0.1 mm) of a multicore wire of 0.5 mm2 effective areal. Just remove the insulation from a standard multicore wire of copper of approx. this size, take two cords or so and twist them together. Use this as a miniature jumper as shown in the photo. First presolder one end of the twisted wire, the part of the wired to be soldered first. Doing so will make the solderpoint more homogeneous and the soldering time will be short and effective. Doing this whit a "blob" of solder is risky as it may float and bridge to other parts. Before you start soldering, “wet” the solder tip by adding new solder, then use a rag to remove the solder this is the way we clean the soldering tip. Then when you are ready, just add VERY little solder to the tip, then you’re ready to solder. (This has to be done just before you start soldering.) Avoid using to much solder on the iron tip. Have no idea of “how many” out there, if any, been doing this modification. Anything more, just yell.. Thanks. Torgeir.

Hi gr5, Thanks for this informative video, real good! Torgeir.

Wow..... Way to go!!! Great creation! Torgeir.

Hi cloakfiend, You should not do the cable thing, just follow the photos above. So, good luck. Thanks. Torgeir.

Hi Sealcat, Great print and it worked out better than I expected.. So, did you check the filament when finished? It's a good thing to inspect "the look of the feeder track" on the filament around the point the feeder wheel was when your print finished. Any sign of grinding here,. etc.? Well, I'll think you have a feeding issue. So, not to change to many thing at a time, we'll do another test printing the same object, but this time you'll be stand by holding your hand lightly on the filament's input to the feeder. This so you can feel the feeding all the time from about 8 mm³/sec., until finish. If you feel that the feeding stops, you have to help with your hand to push the filament in order to have proper feeding -all the way until finish. So, next question, is the print good now, after this additional help?? We might do some hardware "adjustment", if more force is needed. The cover I was thinking about is (this one) now removed: Here is the feeder stepper motor: As "fbrc-eirin" pointed out; the pressure on the filament is a little bit to high, cause it is some flattened. Adjust it back until you see "two teeth" track and leave it there. The idea is not to flatten it, but have a clear track without flattening the filament. It might be a good idea to print a test object that's reflect the problem your printer might have, before going into a more time consuming print. This as lot's people here have done that, and can help in advising better if you are using a known printing object. Happy printing. Thanks. Torgeir.

Hi Folks, I'd simply have to comment here, why – because I'm one of those using "3 in one" oil in my printer. As jameshs said; ... there must be some confusion.. Certainly it is, first; the "3 in one" oil is a "high speed spindle oil" type, containing corrosion inhibitor and cleaning agents -hence the name "3 in one". In 1994 the "3 in one" oil celebrated the product's centennial -100 year! So, this oil have been in "service" for about 122 years today, -and it is still in production! Then to the WD40 "involvement". In 1995 (I’ll think), the "WD40 Company" bought the name and products of "3 in one" and made their own product as "3 in one", a product label for all sort of spray and lubricant variants they offer. So no wonder people get confused here. But, the "3 in one" oil is still the same, even in the new "plastic" bottle! Way back, "3 in one" was used for sewing machines for a long time, then those companies started to "make" their own brand of sewing machine oil. Suddenly stories about how much better this "new" oil was over to the old oil types that’s was used for same purpose over years before.. But the truth is, they're all based on the same type of oil distillates. There is one thing I don’t like with “3 in one”, and this is the odor of the cleaning agent, the odor of Citronella oil. Not my kind of smell ( ), but the positive part in here it’s that’s easy to identify the “3 in one” oil! So, when you finish your oily job, the smells remind you to wash your hands after the oil job, actually a good thing. (Citronella oil is used in soap production and perfume production.. etc. ) When I saw the specs for the “Unilube”, the general purpose oil that’s part of the kit Makershop sell for ultimaker. In the spec. sheet, this oil have a note; “Store in a frost free location”. :( What, an oil do not survive in frosty environment(?), until I’d realized that the plastic container cant take minus temperature. This kind of oils can be stored for some … time normally. I’ve have a small metal can from 1962, that’s still have some oil smelling Cinderella oil! -And I have a new plastic can of “3 in one” bought in 2010! Edit: Forgot to mention the most important thing: Today there is several types of sewing machine oil, new types as full synthetic and so on.. I'll like to see that the Ultimaker recommend the sewing machine oil to be used is; the types based on light mineral oil. Also the issue about warranty and the recommendation for servicing. Here’s two pictures, “3 in one” and “unilube”. This is the new plastic can "3 in one" oil. (The original is a metal can.) Here is the "Unilube", also using a plastic can. Happy printing. Thanks. Torgeir.

Hi Bob, When I built my printer and I ordered all of those connectors from RS Component. For each of the three fans (normally fitted with this one) connector type: PHR-2 P/N: 820-1466 (RS P/N) (Brand JST) For this connector you'll need socet pins (6) type: BXH-001T-P0.6 P/N: 820-1529 The two feeder lines, 5V DC (for cooling upper part of extruder) and 24 V DC (for the two serial connected cooling fans). For this you'll need three male connectors type: B2B-PH-K-S(LF)(SN) P/N: 820-1422 (RS P/N) (Brand JST) These pins are to be soldered. So you'll need some proper heath shrink tube for insulation of the soldered pins. Here's some direct link to RS for the parts: http://uk.rs-online.com/web/p/pcb-connector-housings/8201466/ http://uk.rs-online.com/web/p/pcb-connector-contacts/8201529/?searchTerm=BXH%2C+BXH-001&autocorrected=y&relevancy-data=636F3D3126696E3D4931384E4C446573635461786F6E6F6D794272616E645365617263685465726D325F74656D70266C753D656E266D6D3D6D617463687061727469616C6D617826706D3D5E5B5C707B4C7D5C707B4E647D3F5C707B5A737D2D2C2F255C2E5D2B2426706F3D31313326736E3D592673723D4175746F636F727265637465642673613D78682C206278682D3030312673743D4B4559574F52445F4D554C54495F414C5048415F414E445F4D554C54495F414C5048415F4E554D455249432673633D592677633D4E4F4E45267573743D4258482C204258482D303031267374613D4258482C204258482D30303126 http://uk.rs-online.com/web/p/pcb-headers/8201422/ If you tend to by the tools from RS, do not do that, they are extremely expensive and not worth that! You can buy the same “standard tool” from China for 16.50 USD. Yes I did and had no problem, I’ve to say been using such tools for quite some years.. This tool can be used on “most” of the crimping connectors on Ultimaker2. Crimping tool type: SN-01BM XH2.54 SM plug terminal spring clamp terminals Crimping Tool Crimping pliers For D-SUB Terminals Sq.mm 0.08-0.5 AWG28-22 Here is a picture for your inspiration. You'll see even the original RS parts is made in China! Thanks. Torgeir.

Hi Sander, Yes, you're right it is just about 10 cm longer the original that's approx 704 mm if my memory serve me right. The purpose was to lift the feeder as high as possible and put it at some distance from the back panel, this cause I wanted a better loop radius for less "overall" friction. IE. As little friction as possible wherever the extruder is printing on the bed surface. Thanks. Torgeir.

Great diagnostic! Torgeir.

Hi mbef, Maybe you'll need something like this.. http://no.rs-online.com/web/p/pcb-terminal-blocks/3617667/ Check the pitch, the distance between the solder holes.. Just a shot.. Thanks. Torgeir.

Hi Sealcat, To answer your last question first, I'll guess this is a sound from the small piezo speaker on the board? If there is no stepper movement.. hmm.. My printer have a little "flashing" during start up, but I'll guess the software people never tried to "dress" this away.. Sometimes you'll need to do some delay routines in the software to avoid such thing to occur. Well.. Power supply issues, -but I would not worry about this. -- This looks like the very much known issue with the UM2. Your main problem is the feeder arrangement I'm pretty sure. I'll think you should join in here: https://ultimaker.com/en/community/33678-is-this-an-under-extrusion-issue?page=1&sort=#reply-163776 Cause, I'll want you to try the same thing. My best advice. Thanks Torgeir.

Hi Mickael, You've already got lots of good advices here from Youter, in order to get your printer performing better. It will for sure perform better doing this. I think all your settings is about right, a temp fluctuation of +- 1 to 2 deg C. is quite normal, so no issue here. The only thing that’s not seems to be right is your feeder that skipping a little during bleed feed of a newly installed filament in order to clear the nozzle. I would like to know your feeder current setting. You'll find this adjustment in the firmware at the "advanced setup menu". The current here is normally approx. (1200-1300)mA for the feeder stepper motor. Also, the Z-axis -could it be a down jump in here that start this. Just to be sure.. You'll need a short time print job that's take the printer to the limit.. Yes, I'm thinking about the flow test. It will take about (17 to 20) minute, so this one is easy to do and the answer come right away! Your printer should be able to do this print perfectly, but I do not think so.. To observe what's going on, you should remove the left cover inside your printer, the cover that's hiding the stepper motor for the feeder. Now You have to put a black line (straight radius line from center of the back of the stepper shaft) on the stepper shaft so you easily can observe how the stepper behave during the flow test. You can find the printer flow test here: https://www.youmagine.com/designs/test-print-for-ultimaker--2 If you can’t finish this full test, don’t worry, there is a solution that do not cost an arm or a leg.. Show what does it looks like when your print finished? Well, -then we'll see how to take the next step. Good luck. Thanks Torgeir.

Hi obus3d, I'm very sorry to see this, also to hear that you've been struggling for such a long time with this problem. This is more than "under extrusion", you have some serious error/problem here. Looks like the skirt is OK. -and the first layer as well.. So first question, what kind of filament are you using here? And what is the temperature setting you're using for this print? Did you monitor the temperature to see that it is correct? This is a low speed print, what speed then? Then, -during filament insert/feed and extrusion, -there is some signs that can alarm if something is wrong! This pre feeding with the plastic extrusion out of the nozzle, is it going very fast without any kick back of the feeder? It should continiue with same speed as it started with without any slipping or feedback (assume using 0.4 mm nozzle), can you confirm this? The question I'm ask here is "valid", -if you're using PLA. PLA is the best filament to use for measuring/testing, -this is also the one that's create less problem in general.. Does the feeder grind your filament, preventing feeding properly? Yes, sure I'm asking a few question here, but we need some answers in order to help. Here's many people with lot's of experience, so I'm sure your printer problems soon to be fixed. Thanks. Torgeir.

OK. Here it is. The first picture show the part of the main board of interest, all stepper drivers with the connectors and a yellow mark besides the resistors to be shorted. I've made a detail picture of each of the drivers where you can see the actual short jumper across the resistors. The individual pictures have name that’s reflect the stepper, the ICS name and involved resistor ID. So the following pictures added is: X_U8_R84.JPG (So: the X-axes, IC U8 and resistor R84) Y_U10_R85.JPG Z_U11_R86.JPG E1_U12_R102.JPG E2_U13_R103.JPG That’s all. Overview of involved parts. The X-axes. The Y-axes The Z-axes The E1 feeder (here you'll see clearly how the resistor is shorted across). The E2 feeder So, remember to remove all contacts/connection from the main board before soldering here. Good Luck. Thanks. Torgeir.

Hi spiruline, Check your power supply, the power supply is one of the units that’s work "hardest" in the printer. If the voltage drops down, your fans will suffer so will the steppers, but the processor will still works as it use own regulator delivering 5 volt DC as long the input (your 12 V DC supply) is more than approx 7.5 volt DC. Just my 2 c. Thanks. Torgeir.

Hi Sealcat, Welcome to the community. You have some known problems for sure, but first, you'll need to upload your picture using the second icon from right. This will give us a better quality of the print. Also the video have a very lo volume, so it is difficult to analyze the "kind of" sound that's occur when switching on the printer. For sure you have some under extrusion, can you see any wear/chafing on the filament at the point it stopped feeding? Thanks. Torgeir.

Hi cloakfiend, I would say, people with some experience in soldering can do this, however, they will need some training and the right tools in order to do this. If you want to do this modification, make it on all five stepper drivers! X,Y,Z,E1 & E2! 1) Basically, each point to be soldered in here should take less than a second -or more like half a second! So a few “smart trick about soldering”, a steady hand and a magnifier is handy (if needed) for you to finish such a job! 2) Do some practice on an "old replaced" PCB(from a PC or equal) that's having approx. same size of components as on the UM2 main board. 3) The solder iron tip must have a tip size of not more than 2 mm / 1/16", and between (20-40)W. 4) The work desk shall be very well cleaned and covered with brown paper taped on each sides. 5) Is your working area free of static electricty? Here’s a link to appropriate tools: http://www.conrad.com/ce/en/category/SHOP_AREA_17583/Soldering Soldering kit from Conrad: http://www.conrad.com/ce/en/product/588332/Soldering-iron-kit-230-V-30-W-Basetech-ZD-30B-Pencil-shaped-tray-solder-desoldering-pump-soldering-tip?ref=list (PS. You shall not use the soldering pump for this job.) Or just this type of soldering iron: https://www.circuitspecialists.com/solderingirons This is the one I’m using.. http://www.conrad.com/ce/en/product/588221/Toolcraft-ZD-10D-Helping-Hand-with-Magnifying-Glass?ref=list Here’s a little about soldering electronics components, a little old for our surface mounted components, but else quite informative. http://www.elecraft.com/TechNotes/N0SS_SolderNotes/N0SS_SolderNotesV6.pdf You might have a friend, maybe a radio amateur? This is an excerpt from the introduction of the ARRL handbook, so you know a little about this community spread all over the world. “ Amatur Radio. People who pursue the hobby of using a personal radio station to communicate, purely for noncommercial purposes, with other radio hobbyists call it ham radio or Amateur Radio. They call themselves Amateur Radio operators, ham radio operators or just plain “hams.” You already know a little about the hobby—hams communicate with other hams, around the block, on a distant continent—or from an orbiting space station! Some talk via computers, others prefer to use regular voice communications and still others enjoy using one of the oldest forms of radio communication— Morse code. – International Amateur Radio Hams in other countries have formed national organizations, just as US hams organized the ARRL—the national association for Amateur Radio. These sister societies work together to have a united voice in international radio affairs, such as when governments get together to decide how radio frequencies will be divided among its various users. “ A Radio Amateur will not have any problem doing such a job for sure. This is more or less most of the issues, -but as you said, we need to make an easy step by step procedure to follow for such a job. Well, here’s some inspiration pictures for you to see.. The third hand. Close Up. Thanks. Torgeir

May be, but it's suspicious that there is not such a problem with older versions or with the standard firmware. That's why i think it has something to do with things that were changed this year... Great diagnostic. Torgeir.