2-Pack CR10 Z axis T8 Anti Backlash Spring Loaded Nut Elimination Gap Brass Nuts for Upgrade Ender 3 Ender 3s Ender 3 Pro V2 CR-10 Tornado 3D Printer 8mm Acme Threaded Rod (Nuts)

I bought these along with a Dual Z Axis Upgrade kit for my Ender 3 V2. They can be very hard to finally get threaded on the rods. Once I got them installed, calibrated and made sure everything was level I turned my printer on. I went to full height and them bottom. There was some pretty bad grinding. I did some more adjustments and started a 1h15m print. 40 minutes in, print got ruined. I did the same print 3 more times with the same issue in the same spot. I again adjusted and tried again. Again grinding and ruined print. I thought maybe it was the Dual Z Axis Upgrade kit. I decided the easiest route was to just put back on the stock ones. So I removed the anti backlash nuts and tried the same print. It went perfectly on the 1st time. With these anti backlash nuts installed the carriage is very hard to move and you dont want that while 3D printing. You want smooth motion everywhere. I suppose this may be good if you only have a single Z Axis lead screw. With Dual lead screws these are unnecessary. Ill be returning them.

It didnt match the threads to my z-axis lead screw, had to return.

The face is not flat on the anti backlash screws creating so much play the antibacklash screws completely defeat the purpose of having them installed and I cannot use the stock screw as the connector bolts have been machined slightly too far apart for the stock screw, meaning you have to use their terrible screw instead.

Spent 10 minutes trying to install and could not figure out why I couldnt get both screws in. Then I realized the holes are too far apart by about half a mil. Could not install. Returning.

This is an awesome solution to keep any inaccuracies in you z lead screw from ruining your prints. Polisi3D always has some of the finest machined parts, better most times than the BIG brands. Fit perfectly on my Ender3 and as I said the machining is so good it glides. A work of art for a oldham coupling. Will be buying more for sure.

I installed these by following a video on how to install a backlash nut on an Ender. I compressed the nut, threaded the Z rod and it looked good. However, the gantry still drops at the lightest touch. Perhaps this would work better on a different printer.

Even if you dont use the spring or have dual axis the fact that these are threaded makes thebprocess of using them far far wasier than struggling with trying to attack a nut to thebkther side of the stock version! I used these with a kit here on Amazon for a dual upgraded z-axis on my Ender 3 Pro. The backlash component seems to function but it is a major pain getting the spacing jussssst right for it to workz. Check out the yourube video by TH3D on proper installation of these things ( note it is far easier to get it right by taking your axis completely out of the machine first versus installing in situ).

Most 3d printer noys just make junk toys; and will not have the skill to install these. Which is why there are a lot of bad reviews. Toy printers arent usually machinists. I found these easy to install and they stiffened the z axis a lot. The accuracy is great.

The set comes with two units. On both of them, the threads were too tight. I should have known when I threaded them on (it took too much force to get the Z rods started). Because theyre so tight, it caused a ton of binding. Put my originals back on and I was back to buttery smooth. I really just wanted to try these for fun - turned into an annoying afternoon project. I do not recommend.

I installed these on my dual z modded ender 3pro. Got rid of the creaks and allows smooth movement without binding from the z screw rods being less than straight. Perfect!