2pcs 300mm 8mm T8 Stainless Steel Threaded Rod Lead Screw with T8 Nut for 3D Printer Machine Z Axis

I bought these T8 lead screws to modify my CTC i3 3D printer to remove the issue of Z banding showing on the 3D plastic parts. The supplied couplers and, cap head machine screws and the lead screws themselves were perfect for this. It should be noted that people wanting to repeat this work will need to modify their printer firmware to account for the change in pitch from M8 threaded rod to T8 machine screws with four lead ins. Its possible and quite simple to achieve but it took me a while to work it out.

after fitting this in place of the stock Z Axis rods the print quality is amazing ! I fiited these ona Prusa i3 mk8 clone and theyre the best upgrade I have done, I have to input the gcode m92 z400 before each print to compensate for the difference in rods but its a small price to pay for a quality finish

Got these to have printers running with the same lead screws. There are boxed and so straight. They feel prelubed..

I haven't tested them for practical application yet but the nut slides on these unhindered, the rods look really good and all in all they seem like a really great product

The product arrived quickly and well packaged, they come in a tube together with the nuts and fixings to fix to a 3d printer. The tolerances are good and they are straight and true. The ball-screws are a 4-start thread so you will need to be aware of this is modifying a printer from 1 or 2 start ball-screws. A change in the firmware would be all that is needed to fix this. The nuts spin freely and there are no sticking points. The ball-screws have a protective coating on them when they arrive which can either be cleaned off with a degreaser or left. The ball-screw will meed lubricating when in use though. I have been using them for a few weeks now and i have seen no problems.

I have called this "Not always the right thing to do" because while there is nothing wrong with the product I ran into problems after fitting it to my Geeetech i3 printer. I bought these based on the numerous reviews saying they were the best thing since sliced bread and the fact that I had a lot of Z wobble (Now cured by a different method) on my printer. After fitting and resetting the printer Z axis movement to around 400 mm the home side (Left) kept dropping and so went out of sync with the right hand feed. It turns out that because of all the weight on the left feed (Hot end stepper & X axis stepper) and the fact that the screw thread has such a steep angle the weight was enough to turn the thread and stepper just a little. I checked on a number of forums and found others had the same problem, it was suggested that a single entry lead screw was a way to solve the problem instead of this four entry screw. Not a problem but a lesson learned. Once again the product is well made and the rod is straight.

After reading the reviews saying good rods and that they are straight. I was dissapointed to find that the ones I've received are bent even though they had been packaged well. Going to carry out a couple test prints to see if they cause any print related issues before deciding to keep or returning them.

Decent quality, well machined and packaged. Looks to be slightly better quality ones than I have ordered before.