****** - Verified Buyer
4.5
The rods are straight & the threads on them are smooth, but the rod ends have some burrs, so be careful when threading anything on the rod.The bearing blocks have set screws in them & the inner races fit the rod snugly; HOWEVER, 3 of the 6 bearings I received were VERY unevenly inserted into the blocks. So, I can use them for a 3-bearing build, but I'd have to do some serious fine-tuning to the bearings if I wanted to use all 6.The couplers all seem fine to me so far...nothing spectacular, but should be fine to use.The T-screws provided with these sets aren't incredibly smooth on their threads, and they're a quite a bit loose/sloppy on the rod threads.All-in-all, the rods are the most important part, and the only problem I had with them are the very slight burrs on the ground ends, so 4 stars overall, but I definitely wouldn't want to see how poorly a printer that I put this whole kit into would print!Ender 3 lead screw, this screw is the perfect for for a ender 3. The nut doesn't fit but the screw fits the preexisting one. Was shipped in a tube to prevent bending and it was perfectly straight.I'm using these for the Z-axis on a 3D printer. They are working great, much better than the stock 5mm threaded rods the printer had. The coupler and nut are what I expected. I'm not using the pillow blocks for my current setup, so they were just a bonus. However, the bearings in the pillow blocks are not inserted straight. I couldn't straighten them by hand, I'm guessing I'll need a small C-clamp for that if I ever have a need to use those.I didn't rate 5 stars because of the packaging and the fact that the pillow blocks aren't usable out of the box. Each lead screw was in a cardboard tube (about 1.5" in diameter) with the other parts just sort of bouncing around in there. The lead screws didn't seem to have any damage, but they easily could have with those pillow blocks in the tube. A roll of plastic or bubble wrap would have gone a long way.The items shipped in a tube in a box. Everything arrived as it should and the parts do not show a lot of slop. Gravity alone will allow the nut to spin down the lead screw. Very little slop/backlash between the nut and the screw.The set screws used in the coupler are the right length for the 8mm side, but have to protrude very deeply into the coupler to bite into the 5mm shaft. Longer set screws fixed that easily enough. I also think the set screws should not be at 90 degrees from each other, but at 180 to bite into the two flats on the shaft of the 28BYJ-48 motors.I have not mounted it to the stepper motor yet so I cannot attest to the collar yet, but the pillow bearings are garbage as other reviews have noted. However, the lead screw itself is pretty good and the brass nut runs really smooth. We'll see how the collar is when the new pillow bearings (different brand and vendor) come in today.Evry thing came just fine except the threaded bushing had a small crack. I didnt want to wait for a new one and there will not be much force on it for my application so I used it anyways. Seems to be fairly accurate, guides very smooth, when held upright the threaded bushing will twist itself off by it's own weight. No hang ups on it. Will buy again when neededJust as advertised. Delivered in a sturdy tube so the shaft would not be bent in shipment. This was professionally packaged and I really appreciated this. I am going to build a simple demo mechanism for my little grandson who loves mechanical items. I bought a hand crank for this one which fit perfectly. I will build a similar item with a driver circuit and a stepper motor, but, this one was just to demonstrate a manual version.Very nice quality, I would buy again. Not used for the usual purpose but the bearings seem quite true and the screw is smooth and fits snugly into the bearings
