Linear advance guide - Free and easy print quality improvement

want to improve your print quality for free with Marlins linear advance you can do it quickly and easily [Music] [Music] linear advanced is an advanced feature in 3d printer firmware such as Marlin in essence it carefully regulates the pressure in the nozzle to provide a more consistent output of filament from the extruder with linear advanced tuned you can expect the following benefits it will get sharper corners on your prints flutter more consistent walls and the ability to increase print speed without as much drop in quality before we begin we need to satisfy three prerequisites we will need to enable linear advance in the firmware so you will need a bootloader burn for your printer and a copy of your Marlin firmware sauce you will need a nicely leveled bed that produces consistent good first layers and you will need to have already calibrated your east steps which I have a guide on popping up in the corner right now there are some stepper motor drivers that are problematic when using linear advance mainly the TMC 22:08 when it's in stock top mode or legacy or standalone mode so that means anyone with the karela t silent boards this is a no-go in this video I'll be setting up linear advance on to printers the first is my second SK go that has TMC 2130 s on a SK our version 1.3 mainboard the second is Mike reality under 3 which is currently running in SK our mini e3 that has inbuilt TMC 2209 stepper drivers let's begin with a deeper explanation and then jump right into the step-by-step guide when we move the X Y it will set axes the motion of the printer perfectly matches the rotation of the stepper motor but for the extruder it's different when the stepper motor turns there'll be a very short delay while pressure builds up in the nozzle and after we finished turning the stepper motor there will still be some pressure in the nozzle and plastic will continue to use out afterwards this diagram shows the effect of this while printing we expect to get a perfect extrusion as a printer moves side to side what actually happens is we get under extrusion at the start of the movement as we wait for nozzle pressure to build then we have good extrusion in the middle and then at the end still pressure in the nozzle so we go a little blob until it's gone looking from above we'll see that a primer has slightly bulbous edges created by this effect and we'll see this shortly in our before test print linear advance aims to decouple the movements of the extruder stepper motor shifting them slightly to control the nozzle pressure and alleviate this problem if it's tuned correctly we should see these bulbous edges almost disappear linear advance looks ahead and precisely controls the pressure inside the nozzle by timing the stepper motor more appropriately for this video we're going to be following the main linear advance documentation on the Marlin website it's a thorough page with everything explained well I'll link it in the description so you can read further if you like but we're going to skim through it pretty quick now apart from a couple of main points firstly this video is covering version 1.5 as opposed to the earlier version one that used to be used and the difference is there if you're switching from the old to the new you'll need a new K value for calibration I'm showcasing this on two direct-drive printers but it's even more important to get this done for boat and jib printers the methodology I show in this video will be exactly the same the only difference for your testing on a Bowden tube is that your K value will likely be higher than mine in this video we're going to go through five steps we're going to do a before word test print we're going to enable linear advance in Marlin will then print some calibration patterns probably more than once to get it dialed in we'll save the carry value we learn from that to the firmware and our slicer and then we'll do the same test print again to compare our results for your test print I recommend this simple calibration cube that's linked in the description your test model should have sharp corners it should have changes of direction preferably 90 degrees like here and if it's small like this it will be fairly quick to print and it won't use up too much filament printing one before touching the firmware illustrates the problem we're trying to fix we can see where the printer has slowed down and changed direction there's some subtle bulges it's on all of the edges of the X and the corners of the cube as well on the Y side of the cube we have the same thing we also have just a little bit of ghosting there from the heavier bed moving back and forth now that we have a good baseline it's time to tweak the firmware enabling linear advance in the firmware really couldn't be easier all we need to do is to come to configuration underscore Eddie VH and then ctrl F for the word lean underscore advance then we simply uncomment this line and recompile the firmware this concert number is something we'll be choosing and it has a default value of zero point two two now we get down to the test padding which is what we're going to use to fine tune our K value and get our linear advance dialed in in a second we're going to follow this link to the pattern generator and it's going to help us make the G code for this pattern to be printed on our printer fortunately even if you don't have a deep understanding of how this pattern works it's still really easy to interpret and to set the correct value it's going to print a series of lines and the K value is going to be different for each one so we can make comparisons next to each other so here is the calibration pattern generator there's a lot of settings on the screen but there's not actually that many that we need to use and main priority is making sure we get these base settings correct and if you're unsure on any of these specs you can switch to your slicing program and copy them from there for instance something really simple I'm using a point formula meter nozzle and I can also get my temperatures from here as well a really important one to get right is the retraction distance with my direct drive extruder that's only one for me but you probably find you have six seven or eight millimeters on a Bowden tube setup the printbed is also important to get right because we want this model in the center of our bed not over on the edge and we don't want any chances of collisions now generally all the speeds we can leave exactly like they are you might want to check your retraction speed from your slicing program and if you need to check something like acceleration you can connect to your printer via front of face or octoprint anything with a terminal and then send an M 503 we can see here our maximum acceleration is there and we can copy in the value for me - default so everything matches now for the first run we're going to leave everything standard for the pattern but we will come back and tweak this if we need to for fine-tuning later on this bottom section is called advanced and it's exactly that and for most people that we need to touch any of these settings if you've got any of these non-standard you'll probably know exactly what you're doing but for everyone else you can just leave it to finish up we click to generate G code we'll see the G code here and then we download that as a g-code file I've dragged in the G code into simplified 3d just to preview it you can put it on your SD card and run it from there I'm going to run mine connected directly to the printer just to speed things up here we can see the calibration printing and it works as follows it starts on the left hand side with a slow move then has a fast acceleration through the middle followed by a slow move on the end when this main pattern is finished it comes across the top draws two vertical markers and then fills in the K values on the right when we're interpreting the test grid pattern we're looking for the most consistent line without these artifacts with that in mind we can interpret the standard pattern that goes from zero to a k value of two my most continuous lines are right down the bottom so what I want to do is run a second test where I retest in more detail around these areas and I discard everything up here so back on our pattern generator we're going to come down to pattern and instead of having a ending value of two we're going to set that to zero point four and then when what else stepping to be a lot finer since I've got a much smaller range so I'm going to put that down to 0.05 now we scroll down to the bottom we go generate G code to update what we have here and then we download the file and run the test again here's the new G code apart from the zero we can see we have eight new variations to try and this will help me further narrow down the exact value that I want we need to remove the old pattern and I recommend a credit card to clear the bed quickly ready for the new one the best thing about this test is its over in about a minute and uses very little filament here's my second test and once again we're looking for the most continuous consistent line and we can see that the upper half is still not the best and our best values are probably somewhere around the middle here so what I'm going to do is one final test honing down on these values here so hopefully this will be my final one I've run it from 0.1 to 0.25 me the required detail to choose my final key value for calibration so on this final one they look almost identical we can see some subtle bulging up here and a little bit skinny there but down the bottom I think is still the strongest values if you're struggling to tell the difference then probably any of those K values would be correct I'm going to settle on this one here I think that's the most consistent and that would be zero point one one so I have my chosen K value of zero point one one so I'm going to enter an M 900 and that will tell me that it's currently set to zero and then I can do M 900k zero point 1 1 now I should be able to save that to EEPROM and it should be stored for future prints now alternatively you might want to test this for all of the different filaments that you have because you'll find flexibles will be quite different with the value required therefore you could put the M 900 K line in your start G code depending on your specific filament then it should be in place automatically for any of your prints one more thing before we print the second test cube there are some slicer changes that we need to make you can see here it tells us to turn some things off so for instance pressure advance coaster and extra restart length after retract it also says to turn off wipe while retract or combing it might be called something different depending on the slicer that you use but hopefully you can find the correct setting we can see some of those settings in simplify 3d my extra restart is already set to zero and I need to turn off wipe coasted end is already off and in the Advanced tab there's an option there for wipe as well here's my before and after test cube side-by-side and hopefully you can see immediately that the bulges are vastly reduced for the y-axis the result is not as profound and that's because we have a much heavier carriage moving back and forth with more inertia we can still see that little bit of ghosting overall al extrusion is a lot more consistent I recently run the same procedure on the SK go from second and it's core XY which means it didn't suffer from any ghosting on the X or Y going through this pros this allowed me to print this absolutely beautiful Benjy it won't cost any money so if you're willing to put in the time this is a very worthwhile process once you get going the whole process is actually quite fast to do and I hope you agree that the results while not game-changing are definitely worthwhile one thing to mention is that a regular retraction in the slicer aims to alleviate nozzle pressure and stop is in a similar way so it may be worth retraining this in your slicer now that linear advance is enabled have you tried linear advance are you going to give it a go now please let me know in the comments thank you so much for watching and until next time happy 3d printing g'day it's Michael again if you liked the video then please click like if you want to see more content like this in future click Subscribe and make sure you click on the bell to receive every notification if you really want to support the channel and see exclusive content become a patron visit my patreon page see you next time

Channel: Teaching Tech

Views: 556,445

Keywords: 3d printing, 3d printer, 3d printed, 3d print, creality, ender 3, linear advance, lin advance, la, pressure advance, marlin, k value, calibration, seckit, SK-GO, tuning, how to, guide, step by step, how it works, tutorial, lesson, beginner, e-steps, skr mini, skr mini e3, tmc2208, tmc2130, tmc2209, adjustment, test cube, calibration cube

Id: n3yK0lJ8TWM

Length: 12min 7sec (727 seconds)

Published: Thu Oct 10 2019