Screw Rod,400mm 8mm T8 Stainless Steel Threaded Rod Lead Screw with T8 Nut for 3D Printer Machine Z Axis(400mm)

I purchased this lead screw to make a homebrew dual z-axis mod for my Anycubic Kobra 2 Neo and am very pleased with it.It appears to be as close to perfectly straight as makes no difference, not that that matters too much in my case as I'm using Oldham couplers on both lead screws, but it was still nice to see.Linearity of the thread is excellent as I discovered when constructing my own manually adjustable brass anti-backlash assembly and watching it 'helicopter' down the entire length of the dry lead screw under its own mass prior to lubrication with no tight or loose spots.After lubrication, movement was silky smooth with the only friction coming from the lubricant itself. I really wasn't expecting this level of quality for the price so am extremely happy with my purchase.I've supported it top and bottom with a pair of 628-2RS bearings and a decent thrust bearing at the bottom. The two lead screws are 640mm GT2 belt-coupled with a pair of 40-tooth (to reduce cogging) GT2 gears placed immediately below the top bearings, and tracking is accurate to within single-digit microns.Highly recommended.

RAS