****** - Verified Buyer
4.5
I ordered this part back in april maybe may, its been that long ago I forgot when. It took forever to get here and when it did get here it was just the packaging. The rod was missing due to a hole in the package. Either US Customs retaped the hole very poorly and during shipping it became lost or the package saw enuf wear and tear it ate a hole in the bottom of the package. But, the company was cool about it and sent me a replacement for "free". Had to wait 5 months on this project due to 1 missing rod. Hopefully the company will improve the packaging so it wont eat a hole in it and fall out.Used these on my Prusa i3 that i built from scratch. This is what its designed for its easy to install you have to change out your left and right X axis parts or you could modify them to work on the all thread version but i would advise making the correct parts that work with this. Your Z axis stepps will need to be recalculated if your going from all thread to this lead screw. In the future i will be also adding this to the Y axis because the GT2 belts are good but will stretch over time and will need re-adjusting unlike the lead screw.Got this to upgrade my dad's Geeetech Prusa I3B. The screw is 8mm in diameter while the Geeetech's original threaded rod was closer to 7.5mm. So a new Z-Axis top plate is needed. Fortunately, you can find one on Thingiverse that's a close match but you'll need to modify it to fit the acrylic risers. The thread pitch is actually 8mm and not 2mm since there are 4 simultaneous threads. That means a z-axis steps-per-unit of 400 is needed for the stock Geeetech motors. The print results didn't have the "z-wobble" bands with this upgrade.This leadscrew in combination with a 5x8 mm helical beam coupler So far these look great. are extremely smooth and come as advertized. The packaging was just a bubble wrap bag with some other bags over the product but they arrived clean and straight. I have yet to install them on my 3d printer but see no reason they will not work great. The time estimate on the tracking was way off. They arrived in about 15 days. They are coming direct from China.After install, found that one shaft + nut was not aligned had a spare nut and all is well.RRBhave not installed yet. However, freeplay of nut on the leadscrew leaves me expecting some back lash will still be present on the Z axis. WIll update this note after installation and testing.Quality is decent, screws are straight enough, BUT -- it's not 8mm lead. In 15 revs, the nut travels 121.5mm. So the thread pitch/lead is off by over 1%. That's WAY out of tolerance for precision motion applications like 3D printing or CNC. I was planning on pairing one of these with another (correctly-dimensioned) tr8x8 lead screw, but they'd be ~5mm out of sync after travelling the full range of motion. Completely unacceptable for my intended use.
