Dual z upgrade kit (beltdriven, one motor) for Ender 3 AND Tarantula pro

Alright so I finally got the Tevo back printing away without any deviation in the bottom layers or anything getting smashed and to show you how I did it I'm also going to show you the dual z-axis mod. Now this involves using a belt and two pulleys and adding a linear drive screw to the other side and if you're doing it on an Ender 3 you will also need to remove the power supply which is simply two bolts and other than that the procedure is exactly the same. So basically we'll switch over here that's just running in the background. I am going to go over the process really quickly with you. I'm going to show you what I did and explain to you why it improved the bottom layers of this particular printers prints getting squished and it did achieve the effect that I was hoping for so that's why I use this mod on this particular printer because I can't put this and the 500 millimeter height mod on both because I don't have two lead screws for a 500 millimeter axis just one so that'll have to go on the Ender 3 which is driven by one and runs really fine with one but this one needed the extra lead screw to stabilize the right side of that x-gantry because I was having real issues where the left side would raise up and the weight would cause the right side not to at the beginning of the print and I tried raising and lowering my ZN stop and it just wasn't having any effect it was just burying the mount it was squished so tightening that eccentric bolt on the right side would not get it to grip enough either so adding this lead screw totally evened out the plane so it raises at the exact same time and is giving me the effect that I want my layers are no longer getting smushed by the weight of that rail dropping on the first couple of layers so I'm very happy with that but let's get into the process all right so the very first thing I'm going to do is attach the holder on the right hand side you can see I just pointed out there's one on the left hand side this is basically a bearing and a mount that goes into the v-slot rail here and then I'm going to take and put the bracket on the back don't really have anything too tight up on the top yet just tight enough to hold it in there that way I got a little bit of play in the lead screw and I'm going to one of the time remove the nuts from the back of the wheels pull out the shorter bolt that is in there and it took some doing on the first one because the odd angle I was at but it wasn't too big of a problem just patience and then basically put my longer bolt back through there add a spacer and then the plate and then we will put the nut back on the other side and I'm basically going to do this for all three wheels and this is what's going to hold my x-axis onto the lead screw and it's pretty effective I mean there's three points of contact as long as you get them all snug this one has the eccentric bolt on it I was a little bit worried and in fact in a second here you'll see me yep I just dropped a washer and I'm looking under the printer for it and I fished it back out I was most worried about this one going in so I put it in second in actuality the third wheel on the bottom gave me the most trouble so in retrospect I think I probably should have done that one either first or second and then done one of these other two last but it ended up working out it went on it takes me a minute longer than the rest you can see I was struggling with it a little bit but I did get it to work and eventually had all three of them on there I actually had to loosen my belt tensioner to get enough play to get it out of there so that also might have had something to do with the issues I had with the bottom wheel but I did get the bolt through there get the wheel on there and I tightened my tensioner back down and then I proceeded to tighten all three I didn't tighten any of these down completely until right now then I went around and tightened all three of them basically to make sure that I could get everything lined up with the holes where they need to be and then just kind of hold them with my wrench and tighten them with the allen key so this is me sliding the z rod in there I do a lot of playing around with it once I get it set there's a little more tension on the belt and now I need to add the pulley to the top left and then attach the belt now this kit does come with a tensioner that goes right into the v slot in the middle I didn't actually need it I actually it came out about perfect I need I had just enough tension on the belt when I tightened everything down that it kind of strums like a string and doesn't uh doesn't lose or miss anything so now we're homing the bed we're gonna home everything and it does take quite a bit of adjusting on this right hand side here to get the left and right level and if the sound were on right now you'd hear some funny grinding noises that's why I stuck my hands in there real quick and I'm basically just reaching for the bottom of the lead screw and once I hit the bottom I'm going to stop it and this position here is where I reached over and moved my end stops up to to adjust for the fact that I'm not going all the way down anymore so I did lose maybe three or four millimeters of height by moving my whole setup upward but it is so far accomplishing what I wanted to accomplish you'll see here at the end of the video I'm basically raising and lowering this by the manual control on the display with the control knob and do this several times a couple adjustments to the couplers at top to make sure that the tension on the belt is where I want it to be and I'm just moving up and down in short movements to make sure I don't hear that clicking noise I was hearing earlier I did end up hearing it again when I did a super long travel all of my short movements any movement that the printer would make while running was more than accurate enough you could see there a little bit as the right side lifted up that it wasn't quite lined up so I just continued to make adjustments this was probably the longest part of the process playing with everything getting it where I want so finally I decided we'll take what's left on the build plate here off and we will start the leveling process I did have to again lower the end stop just a little bit from where I had raised it to in order to get the bed to meet in all four corners and then I tightened the eccentric nut on the right a little bit to make sure that everything was the way that it needed to be so this leveling process was a lot more in-depth and longer than most of the ones I do but I wanted to be thorough and make sure that after changing such a big big thing on the right hand side drive here that everything was lined up and set up the way that it needed to be so here I am basically just turning everything and making sure everything's moving smoothly and I finally adjusted that end stop one last time and I'm gonna level it out one more time and then we will go ahead and start printing and see if everything has improved the way that we hope it has all four corners and go around again and make sure none of those spots got messed up yep so I don't go all the way around twice I hit three corners twice and then we are getting ready to start a print so I angled my camera down a little bit we went to turn it on this was the moment of truth here as we're getting ready to start a print it did take a minute to heat up so I paused the video came back and it should be ready to start any second now there it goes and this is still sped up so I'm not running my printer as fast as it looks like but I was very happy with how things went down and I could tell immediately when it moved up to that second layer that things weren't getting smushed the way they were before so really excited about finally getting this thing up and running perfectly that was my final issue was just that first layer squish and or not first layer squish it had nothing to do with adhesion it was the fact that the right hand side wasn't raising up so it was the weight was pushing down on the model when the side with the lead screw would rise it thought it would get up finally it would pull the right side up with it but not until it had drooped down in and destroyed the model right so now that we're confident with letting that guy run on the longer print I'll show you some of the prints that I've done and the difference here in quality now as you can see this one right here is really blobby at the bottom and it's got that artifact about a didn't get caught on the rise so this definitely fixed my problem of those first few layers getting squished and the problem was that as this side would raise up no matter how I tighten that eccentric nut I couldn't get it flush with the bar so this side would sag basically until that end got high enough to drag it instead of raising it as it should by putting the second linear screw in there it basically pulls them both up at the same time which fixed my problem which is great so I did have the other print that I redid that was on the raft just a little knob and this is actually for a belt tensioner I already have one in here but I had a hard time getting it off of the raft and I actually had to clip it away in most places these ones took a little bit of prying but they pretty much just popped right off and that is a significant improvement and also lets me know that those bottom layers are no longer fused together so all in all the dual z-axis upgrade on the Tevo Tarantula Pro was pretty simple it is the same process for the Ender 3 this kit is actually made for an Ender 3 and it went right on without any problems does take a little bit of adjusting to get it right once it's on there but once you have everything leveled out and ready to go I have a significant quality improvement in the bottom layers of my prints and haven't been having the issues that I've had before so this is definitely an improvement as always this channel is brought to you by these fine patreon supporters if you'd like to support the channel on patreon head over to www.patreon.com slash technivorous all right guys that's going to be the end of this video as always thank you I'll put a video up right here that you can check out for more of our stuff and if you're still here and you haven't already why don't you click right here and subscribe to the channel