Fix your Z axis with Oldham couplings, dual z screws & thrust bearings! 

I can't believe you don't have more subscribers! Your videos are awesome and extremely helpful! Thanks for the vids

capturing the lead screw in that lower block you made is actually working against you. Throw those away, make a set screw collar that will go below your upper bearing block. Basically sandwiching the upper bearing assembly. By doing this you now have only two points of the leadscrew captured, now the oldham coupling can easily adjust givining you zero bind between the two points the leadscrew is captured. With your lower block you have the leadscrew captured in three points with only one of those points able to adjust, no bueno amigo.

My soloution was to run an SKR 1.4 Turbo which has the ability to run my two leadscrews on their own motor and driver thus enabling G34 to be run to level the gantry before each print, I wouldn't mind adding the other fix's you made though, the use of thrust bearings is a very good idea! +1 very happy new Subscriber, Merry Christmas my friend and a happy 2023!

Wow I love your attention to detail and a pure engineering perspective. You really did consider everything, including putting a load on the oldham coupler. I hope you added a little lube to it.

Excellent convincing engineering/scientific approach to the problem. Kudos ! So many "upgrades" are iffy as to cause and effect and questionable improvement. My main question with upgrades is cost. The parts listed are over $100. I guess there is satisfaction in substantially improving poor design, and if one has the time as a hobby its great. But my dilema, aside from time, is I start looking at what better printer I might be able to afford by just paying more. This fixes Z-axis, but with so many other upgrades needed particularly on older Enders to fix inevitable problems, etc. it starts running into some real money- dual gear extruder, all metal hot ends, 32 bit motherboards, direct drive, glass printer bed, and on and on. Before long you're close to a no hassle Bambu P1S or ... But thanks for a great video, at the very least teaching to be very analytical and thorough about these problems.

Praise be with the algorithm! Really interesting, even though i don't use my Ender3 anymore

Separate comment - What "I" did to fix my issue, was to just move the wave washer, from the back of the motor, to the front. No more Z banding, even printing at 200mm/s in vase mode. Higher shows issue, but that is because I'm still using rollers instead of rails still. This is with printing LW-PLA (light weight, micro foaming PLA for RC planes and drones). It's like printing in hard mode, because of temps and humidity dictates how much it expands.

I imitated the working principle of the thrust bearing by using normal bearings (I don't know how it will work for long-term use), I think it worked, the z movement is very consistent, I ordered the oldhan coupling and it is on its way (I tried this way because I did not want to order a thrust bearing from Aliexpress and did not want to wait)

Oh, man! This is an absolutely great upgrade ever! I can’t wait to see the next video! Keep it up mate!

Nice solution. I wasn't aware of the spring washer in the motor, so thanks for highlighting that. One further improvement you could make is to use self-aligning bearings - any bend in the shaft will cause angular misalignment that will require a small amount of lash to prevent the thrust bearing binding. Maybe an SKF 108 TN9 would work?

If your z stepper driver if burning, you are likely binding. Reversed wires just causes jitter. Before you install the new main board make sure everything moves freely. Guess how I know 🤨. You gave me a better idea how to solve the downward force on the stepper. Add the thrust bearings between the collet and the stepper on the bottom. Then the load is put into the body of the stepper. I just ordered the parts, I will see how it goes. Using klipper you can run multiple MCUs in theory you could use your old board to create an IDEX.

I had an issue with my B Motor running in reverse. Swapped the blue and green wires. But it made a horrible noise. Upon experimenting, I discovered it was necessary to reverse all the wires to make it rotate in reverse. 1234 ->4321 SKR1.4T

I'm glad I stumbled across this video, I have an Ender 3 Max and its hard to find a dual-Z modification for them being a oddball mix of Ender 3/CR10/V2 parts. I don't want one with dual steppers, as I don't have a spare driver on my main board and running 2 steppers in paralell from one driver makes keeping them in sync a nightmare, particularly through power cycles. So I was looking at the types with the tooth belts, and they all seem to have the limitations that you highlight in the video. The video has made me think about it however, and it seems that by choosing parts myself I will be able to make something that will work reliably, I like the idea of mounting the Z stepper at the top somehow, it occurs to me that maybe making the pulley on the stepper a little smaller than the ones on the lead screws will reduce the load on the stepper and make missed steps less likely - this will require changing the Z steps but thats just a matter of calibration. I like the idea of the Oldham couplings, I'd seen someone else use them but forgot the name and where I saw them, so thanks! I think I'd make a block at the top to stop the lead screws pushing up or down, so the lead screws can be free at the other end to allow the Oldham coupling to do its job, but I guess that might mean some experimenting. This is certainly a thought provoking video, and I look forward to seeing how you fix the remaining issues and what results you get in the next video.

What a bill for a $150 printer! I believe you'll exceed the budget of a flawless printer.

Good video. I've burned stepper motors as well. Thanks for sharing the good and the bad.

A possible alternative to a top mount that doesn't require this much reworking is to print a cubic shaped part that is fixed to the top plate of a bottom mounted stepper motor, with a slot on top of the part for an axial bearing. Fix a flexible coupling to the stepper motor shaft and center it. Put the printed part on top of the stepper motor and screw it down, so that the flexible coupling ends up inside the printed part (ofc it should be printed out of something that won't be melted by the stepper motor). Put an axial bearing into the slot on top of the printed part. Put an unlocked set screw collar and a shim onto the lead screw. Put the lead screw through the axial bearing and into the flexible coupling. Center it inside the flexible coupling (that could be a bit tricky). Lock the set screw collar on the lead screw on such a height where the lead screw can rest on the axial bearing while not compressing the flexible coupling. Voila, now the weight of the gantry is kept off both the flexible coupling and the stepper motor shaft, while there is some angular flex between the shaft and the lead screw.

Nice video. I'm looking forward to seeing if your mods improved the Z axis.

Hi! there IMHO, wouldn't you introduce unnecessary wear and tear to the dovetail surfaces on the oldham couplers if you were to place it hanging on the gantry? However, if the gantry is made to rest on the oldam couplers, then the weight of the gantry with gravity in our favor will mitigate for any play on the Z direction. And the weight of the gantry will always press against the oldham couplers and correspondingly to the lead screw to also mitigate backlash. Anyways thanks for sharing this very informative and helpful video to mitigate Z banding and other Z related issues. Cheers and keep up the good work.

I have no idea what's going on in these videos, but they are #oddlysatisfying to watch

Not perfect but better than most! Geez thanks man! YOU FREAKING ROCK! 🤘 ❤

Why did the motor driver catch fire? My consideration is that it is not a short but a step-out that is caused by the difference in wiring, and the motor driver should not burn. I would like to know more about the cause of the burnout.

More than anyone should ever have to do on an Ender. The right side lagged behind because you had it overtightened. The left/driven side needed to have the X gantry removed and the X gantry screws tightened way down as well. Then the left, driven side needed to be properly tensioned with the eccentric spacer on the V wheels. The oldham coupling on the driven brass nut is a wonderful idea though! You do not have enough engagement with the Z axis driving gear though. You need to have a majority of the gear engaged with the belt. Some idler bearings will solve this.

You are on top!

Incredibly well made video! You did an excellent job of describing these issues.

Great video , i am looking forward ot the next installment

It's not the couplers, it's the T-Nuts. Machining on a 2$ part is just bad and wobbly, use POM instead those wont wobble up and down. Those are molded and much more precise. Did that yestersay on m y cr10s pro v2, dial gauge reports perfect movement now. Dont use anti backlash nuts, regular ones + Z-sync is key.

Awesome z axis video !!! I did not skip anything 👍

plz give links to all small parts like the new belt ,pulley etc...

Could you please add the stl files for the dial gauge mount to the description?

Great project, great details! A couple things. One, I’ve got an Anet A8Plus, which has dual z screws and dual steppers driving them. However, I’ve got a bent screw to replace and when I do it, I want to replace both. The oldham couplings, gantry mounts for the lead screws, your custom block at the bottom and the Gantry re-inforcement rods look like they would be a GREAT upgrade path for it! I don’t need the additional stepper you placed at top, nor the belt, etc….. but, looks interesting! Anyway, good stuff! Question though, sure the stepper drivers are soldered but couldn’t you just de-solder the bad one and replace it? I’m curious, I would think that would be easier than a whole board replacement and cheaper.

Lamento pela placa! ótimo vídeo para ajudar os iniciantes. Porem eu recomendaria comprar uma SKR2 no lugar da placa original. :D

Can share the STL files for the housing second lead screw?

Would putting a thrust bearing between the coupling and case of the stepper motor fix putting the gantry weight on the motor shaft?

Will you also share where or what to order to follow up your solution 🤗

Very well made

you can replace the driver on the pcb

great video! It's a shame you burn the mother board... I hoppe whe will see the final results😉 May you put the files for the material?

It would benefit all us not as wise, to have links to the items you use in this video!

Can you place links to everything you used? Especially the nut you used

The oldham coupler will introduce a little slop in the Z axis.

So did you remove the spring washer and from the stepper motor and just attach the alloy plate? Or did you do something else first? Also where did you get the oldham couplers from, I read some reviews that some have had terrible tolerances, so I would like to find more reliable ones. Thanks

1:55 are you showing us an Ender 3 with a stripped motor screw? Only time I see that bend on an extruder tensioner arm. Lol. Actually, looks like the whole thing's loose, at 4:30 you can see another side crooked. And a lot of the time that elephant's foot imo is contributed to everyone saying their backlash nuts should be loose. All of mine are snug, not tight.

Did you make this dial indicator mount? I was looking at doing something similar.

#2:44 - how is the part attached to the indicator lug called / where can I buy one?

Great project and a lot of love you give to that ender. I'm just wondering about two things: (1) how can the stepper driver burn by swapping two cables. AFAIK swapping two wires will never burn the motor nor the driver but instead either change direction or let the motor only wobble instead of move. And (2) I checked how much weight my stepper motor needs on the axis until it moves and it is around 3kg when the spring is compressed and it starts moving. Can't imagine how this is a problem. Sure it is better to avoid any load at all to the axis like you do now, but does this really affect print quality?

Supper nice video. You earned my sub! Thanks a lot! Can I know the parts specs and product links if you have please?

Good videos please continue

love this video, but makes me sad to look out for this in the future. i am currently having a big issue with ringing and trying to fix it, i am looking for any information regarding z axis and how to make it work better. forgot to ask if linear rails would work to fix issue and be less complicated to diagnose and dial in?

Rule of thumb in engineering. Minimize transfer of loads as much as possible.

Hm why hanging the rods with bearings from the top`? Why not leaving the motor downside und putting a bearing on the motorshaft between the Motor and the Couppler on the shaft so the bearing takes the downforce and not the moving motorshaft. So it should stay stable when pushing the bed upwards because the bearing supports the coupler? So your able to do it on both sides and unse G44 for Gantry squaring with BL-Touch? Anyone tested?

Why would you order the part from aliexpress when you can get it in like a week from amazon?

no link to purchase the dial gauge?

If one cannot spend $800, what would be the single most effective thing to buy to help z axis?

I am quite surprised. How did you destroy you stepper? Did you let a full print go without checking? Usually, you can go ahead with the wrong wiring, and visually check, but for it to damage the driver, the current has to be very highh, or the command was very long

Link to where you can buy Oldhams?Please

Where can i find the rigidity kit for an Ender3. I can’t find it on Alliexpress…

Learning costs money!

Great video!

Bit of research before to buy that 3D printer, could make you save a lot of money i think.. ;-) Cheap + precision doesn't match ( that's why most of people that want things well made, buying German tools and stuff ) Surely if you were checking the Z axis error with a "chinese" comparator (rather than a well made and precise Mitutoyo ), you shouldn't have noticed that error .. ;-) Plus everyone that buying 3D printers made by aluminum extruded bars , cant achieve the rigidity of a Stainless steel body , obviously aluminum bend easily than Steel ;-) ( Nice video anyway , surely many people will thanks you )

My enders do not suffer from this. Instead my dual z printers are a pain to level and keep level. Loading filament misalign it

There are two pin outs available commercially for 4 wires to six pin stepper motors , either pairing pins 1 & 3 plus 4 & 6 or pins 1 & 4 plus 3 & 6. Get a multimeter and do a continuity check on the pin pairings to check which pin out you have on each stepper motor. You can mix the types if you have to on a build, just customise the lead end by unclipping the tiny lead terminations and swapping over pins 3 & 4 as needed. Assuming a random wire will work without testing what stepper pin out you have compared to the board, rookie mistake..... Also you can use parallel or series wiring of paired steppers but not recommended at all either way. About the only application you can get away with it is on a couple of low use Z drives that sit doing nothing most of the time. On higher grade machines with laser cutters etc. you always go single motor to multi drive via belts on same axis, with dual motors if one fails you can skew the axis badly and blow the machine/enclosure across a room, just happens on hobbyist home 3d printers you can get away with lot's of bad habits as the masses, speeds and forces are usually low and slow so failures are non catastrophic. (exception is my VzBoT that has some serious forces in play, with full enclosure being the only option with 4 x 48V steppers driving the print head gantry in AWD mode)

I feel like it does't improve anything by placing the step motor on top and use a belt. RIght now, with your thrust bearing which I really like that idea, the entire weight of X Axis is now supported by the two lead screws, and nothing will be compressing your Z step motor.

I wish I saw this a year ago.

aww i wanted to see result and how do you compare this to dual z stepper with a bl touch for auto z alignment

Most of the Z layer problems on these cheap Ender 3's / clones come from the leadscrew not having a supported bearing bracket at the top. The spin center shifts and moves around as it rotates with layer changes and causes inconsistent height travel. There is no need for all the other "fixes".

At some point I need to accept that eventually I’d be better off getting a rat rig or voron rather than upgrading my ender more

Stepper drivers soldered in place means they can't be replaced? Wrong. WTF?

Super

I burned the mainboard the same way...

Wouldn't making it an enderwire would be cheaper and achieve the same goal?

Brass fittings will not work. Checked. You need magnetic couplings. As in the video- "Fixing Z Wobble from 20$ Ball Screws with that simple device" Author MirageC.

elephants foot is from too high a bed temp too high first layer temp and lack of cooling nothing else

I would buy better mobo

Wasted Effort an interesting but almost totally incorrect solution.! First... BUY and Fit : Collet type motor to Z screw connectors. These are the ONLY connectors that actually work as intended. Also 4 start Z screws produce a guranteed Sag loss of Synch problems. Simply Fit a Single start screw. Cheap easy and Effective Not only does it eliminate Z issues... it Increases Z accuracy by a factor of 4 .. true.

just get a newer printer

big oof.

man just get an SKR mini off amazon for same price and have it installed by end of the week. No arduinio needed, just flash the bootloader with VS Code, plug it in and enjoy the significantly quieter printing experience.

I didn't know about Oldham couplings and, definitely, the axial load is something to be further investigated! There might be better implementations for those problems, BUT... CONGRATS on the investigation and demonstrations! This type of video pushes the hobby further!

I can't understand why you only have 1.76k subscribers. People are crazy! Your video is way beyond awesomeness!

I went the route of using 2 stepper motors on the z, one on each side, would all the other stuff still work?

ima beat you up if you for real bought another stock board to replace the original when you can get proper boards and have independent dual z and controllable fan ports and and and so on so on

10:20 Not sure how you managed to burn out the drivers, because swapping any of the 2 wires going to the motor, just makes the motor move the opposite direction. So what you should have done is move the Z axis to the middle of it's range, so it can move in either direction without crashing.

I just did Kevinakasam's Dual z belt mod and I have absolutely no z banding now and it wasn't too hard to do!

Great mod! You're gonna want more teeth engaged on that z stepper also. Maybe a pulley or two to force the belt to wrap and engage at least half the teeth. With only one or two teeth engaged the belt can flex or just skip altogether.

Nice job! BTW, a big merry Xmas to you and your family! 🎄

Nice to see my oldham coupling here :) good video ! Thanks

not sure how you killed the stepper drivers easily because ive had wires the wrong way before ive never killed a stepper driver before. but then again i use ones that are not embedded so maybe thats the issue the embedded ones are weak. seems like you kind of made it like a i3 style z axis.....almost anyway

Belted Z is or coreXZ is the way to go 😃

Extremely well made video! I really like how you've iterated through the root causes and demonstrated the issues with the dial gauge.

Can the issue of the gantry weight exerting pressure on the motor shaft be resolved by inserting a thrust bearing between the coupling and case of the stepper motor?

The BLV kit had no issues with nuts holes spacement, the issue was your nut. It was not the correct one.

Wobble Wing and Ballscrews?

Un video fantastico, sono alle prime armi, mi diresti come hai fatto per creare una cinghia chiusa per qui.Grazie.

Thanks for finding that wiring issue so I don't have to.

hot sparkels of metal can get sutck on your glass bed

I love your videos! ❤❤❤❤ I've learned so much about 3dprinters from you and you teach/explain concepts very well! Thank you for your work! 😊😊

Will this work on a cr10s pro? I have the rods installed. But been having z wobble with tall prints.

Since the pulley holding the leadscrew is already hanging on the bearingblock, there is no need to move the stepper to the top. The weight of the gantry is then supported by the bearingblock and not by the stepper.

Nice video, thx

I added the oldham couplers and anti-backlash nuts from TH3D to my CR10-Max (because they are already cut-down to fit the CR10 properly) , this stopped the gantry dropping or sagging and helped Z banding. I now added thrust bearings, and made sure the top if the stepper motor shaft was not quite touching the z-axis lead-screw. This seem to have solved all my z-banding. Thanks.