Two Z banding fixes for your 3D printer from the community

that banding will ruin the quality of your 3D prints and it can be hard to eliminate so today we feature two Community designs You may wish to consider to combat this frustrating problem [Music] [Music] Zed banding also known as Zed wobble is rarely seen in modern 3D printers but if you do have it you'll know about it and you will hate it it can be very hard to find out the exact problem and therefore to fix it in this video we're going to test two designs by my patrons that might be able to reduce the problem on your 3D printer we start as always by asking what is said banding and the most classic example I could find was this thread by app Jaws 1 in The reprap Forum as you can see from the pictures vertically along the z-axis we have a series of horizontal bands where the width of the layers appears to swell and contract at regular intervals set banding is instantly recognizable but it can be extremely hard to diagnose the exact problem for instance the example in this great video by Stefan from CNC kitchen where he demonstrates the effect that an unstable bed temperature can have with a thermal expansion and contraction can make the surface of the bed move during the print and cause banding most of the time however Zed banding is caused by mechanical misalignment or faulty Parts such as a bent lead screw and the solutions we're going to explore are targeted at those problems onto my Target printers for this test and the first one is my Ender 3 and when I was installing a second Z lead screw and super motor I experienced set banding if everything wasn't aligned perfectly with some fine tuning I was able to eliminate the problem but recently in a video where I was setting up input shaping for Marlin I thought the layer sacking could be a little better not necessarily anything wrong with the z-axis but worth experimenting with the other Target printer is my cr-10 Max a go-to Workhorse for large objects because it's fitted with a large nozzle I have noticed that on some recent prints there is some subtles at banding at regular intervals on the vertical walls I say subtle because although it's obvious in this footage it only occasionally shows up and when it does it's only cosmetic rather them being prominent enough to feel anything but a flat vertical surface so my cr-10 Max is an obvious choice for these fixes to evaluate properly I need a test print for before and after which I've created and uploaded to printables the design is pretty simple and should be printed with zero infill no top surfaces and the Z seam at the back the aim was to have told geometry that was still quick to print and used minimal filament my Ender 3 test print shows the inconsistent layer stacking that I'm talking about which is shown really obviously when you put a light directly from above none of these bands are repeating however the cr-10 max print with its 0.4 millimeter layer height looks beautiful until you once again put the light directly from above and that just shows an extremely subtle repeating pattern on the vertical wall with our bass lines in place let's examine our two potential Solutions the first is from my Patron Derek and there is a z-axis motor mount with an integrated axial thrust bear and as you can see from the pictures Derek has tested extensively with different designs and the difference between the worst and the best is profound per stepper motor you'll only need one printed part but you'll also need one of these axial thrust bearings per stepper as well being in Australia I clicked through and followed the link to get the exact ones but the specs are here in case you're shopping from elsewhere and to make life easy I've got an Amazon Link in the description when printing this you need something more thermally resistant than pla such as petg and there is a lip on the underside that will require support from the build platform only and once printed the only post processing required is removing that support material now let's have a look at the axial thrust bearings as you can see they come in three parts and upper half are lower half and a race in the Middle with the ball bearings in place they allow rotation but they're particularly good at supporting weight from top to bottom compare this to a traditional ball bearing which again allows rotation but instead supports load heading towards the center ball from the outside this stepper motor has seen its best days and has a really large amount of axial play and this is one specific situation that this modification can address but even on a stepper motor that feels solid if there's enough vertical load on the shaft you can have some flex and this may introduce dead banding so this modification is good in those cases too I'm going to install this off the machine for clarity and our first step is to place the mount over the top of the stepper motor and then secure it with M3 bolts I found that M3 by 20 for the back and M3 by 10 for the front was pretty much ideal but this could vary from stepper motor to stepper motor depending on the depth of the threads once the mount is secure we can drop the thrust bearing down from the top making sure that it's centered before going any further you'll need to install some M5 bolts and t-nuts ready for the mount to bolt onto the Extrusion this is designed to work solely with a rigid coupler between the output shaft of the stepper and the lead screw because a flexible coupler can allow vertical movement the coupler is inserted from above resting on top of the axial thrust bearing if you've got a bad stepper with a lot of play like this one you want to push the shaft upwards before tightening the coupler as this will remove any vertical play the mount will bolt onto 2020 Extrusion and then the Zed lead screw will lower from above and you can either insert a ball bearing between the lid screw and the output shaft to make sure they don't rub unevenly or do what I did and leave a small Gap once everything is torqued up the mod is fully installed and there should be no vertical movement at all on the lead screw the second is from my Patron Patrick and takes almost the opposite approach allowing The Zed stuff to float in the X and Y directions inside this printed cage to build the cage there are multiple files that need Printing and the most unusual Hardware required are 48 three millimeter ball bearings again to make life easy I have a link to a set from Amazon posted in the description because the stepper motor sits inside a cage this will only be compatible with steppers that are around 32 millimeters High which is very common there's multiple parts to print for this one and this is what you'll need if you're doing it for two Z steppers there's two of all of these parts apart from bottom Block B which has a left and right version like before pla might get too soft against a hot stepper so petg or something else that can handle the temperature and here is a set of Parts printed for a left and right Z stepper setup everything is a duplicate apart from bottom Block B the assembly here is a little more involved but we do have step-by-step traded instructions to assist us the first thing we need to do is to drill out eight holes with a three millimeter drill bit that includes the two holes in top bearing B the two holes in bottom block a the two round holes for the connector piece and the two holes on the short side of top bearing a these are the holes with the nut traps behind them with this out of the way we need to join top bearing A and B pieces as they'll be permanently joined together we need an M3 thread in the remaining two holes of top bearing a and if you have an M3 tap you can add them this way if you don't you can drill out the holes with a 2.5 millimeter drill bit and then carefully cut the threads with an M3 bolt once the threads are ready we can apply a small amount of glue between the two holes place the B piece on top and quickly insert two M3 by 12 bolts once they're completely talked up the tips of the two bolts should be flush on the underside each set has four nut traps where an M3 hex Mount needs to be inserted and it's easiest to insert them by pulling them through with another M3 Bolt here they are in place for the top piece with another pair inserted in the bottom block time to insert some ball bearings and I highly recommend tweezers for this job you'll notice that there's 12 slots per set of parts and each of those slots will take four ball bearings amazingly I didn't drop any on the floor and lose them which I thought would be a certainty for the top piece there's a little lip so after dropping them on top use your finger to push them into place that's 48 ball bearings per side and we're ready to go the bottom is mounted on our Extrusion first and if you push hard enough it will clip into place some printer designs will also let you slide it down the top of the Extrusion bottom Block B must be matched to the left or right side and the arrow should face the Extrusion it rests from above and should be able to slide from left to right the top piece is designed to trap the bearing so they don't fall out when inverted but if that's not true for you you can always put the stepper motor upside down trapping the bearings in place as you put it back the right way the stepper motor then slides down from above taking care to line up the plug with the cutout in the bottom piece at this point the assembly should look something like this the connector goes on to join the top and bottom using M3 by 6 bolts not too tight at this stage in four bolts and t-nuts can be used to secure the top part to the Extrusion and after this you can test that the stepper motor is free to move in X and Y but can't move vertically up and down like our first design a rigid coupler is used to join the output shaft of the stepper motor to the z-axis lead screw and again I'd recommend a slight gap between the two you can test to make sure that everything rotates freely you have no vertical play but the stepper motor can move in the X and Y directions and that is how we assemble each of these designs trying to achieve the same purpose yet with different means Derek's design ideal for removing vertical play and supporting really heavy components above and Patrick's design ideal for allowing X and Y play to correct for bent rods and misalignment clearly these were just demonstration installs and the next step is to install them on the machines properly and do some follow-up print tests when you install a zxs stepper onto your machine for real it's important to loosen the mounting bolts move the z-axis up and down and then bring the nozzle down to the home position this should get everything aligned as much as possible and you can then tighten the mounting bolts you'll also need to get the x-axis Gantry square and on the end of three I'm running independent dual Zed steppers which means I can use g34 for this to happen automatically with tremendous accuracy whereas my cr-10 Max still has synchronized Zed steppers which means I needed to use some Timber blocks to square everything up manually with each Target printer receiving one of these mods it was time for some test prints and as you might expect I run the exact same g code for each machine as the Baseline test print and after that I switched the two mods between the two machines and run the exact same G-Code for a third time here we have the results for the end of three and to be honest I can't really see any Improvement here that leads me to believe that the inconsistencies I'm seeing are probably coming from the highest speeds I was using with input shaping rather than anything wrong with the z-axis and I'll have to troubleshoot elsewhere and now the results for the cr-10 max which look glorious until we put the light from above in which case we see once again the results are pretty much identical I can see that these mods are working as intended so that just means that the problems that they're designed to fix aren't present on my two test printers both Derek and Patrick have got great results on their own printers thanks to their developed designs although they weren't suitable for what my printer required it doesn't mean that they won't be for yours so we should appreciate the fact they've put in the time and effort to release these mods for free so they can help others sometimes that's just the way it goes I do agree with the theory for both mods so please consider them if you're suffering from Zed Wobble frustratingly the printer that needed this the most is my neglected end of five but it uses a completely different and incompatible stepper mounting for the z-axis with that in mind I'm asking you to share your favorite Zed banding fix let me know what it is in the comments section thank you to those in the community trying to help others for free thank you 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: 114,632

Keywords: 3d printing, 3d printer, 3d print, 3d printed, z banding, z wobble, problem, troubleshooting, fix, tutorial, what is, alignment, bearing, ball bearing, creality, ender 3, cr-10, max, how to, step by step, free, printables, leadscrew, binding, bind, lesson, couler, rigid, align, install, assembly, portzal3d, djos, teaching tech, artefact, vertical, artifact, surface, quality, improve, mod, upgrade, modification, improvement, test, testing, test print, test tower

Id: snM_NXr4SCo

Length: 12min 55sec (775 seconds)

Published: Fri Feb 10 2023