Iverntech 100mm MGN12 Linear Rail Guide with MGN12H Stainless Steel Black Carriage Block for Ender 3, Corexy, Tronxy, Delta Kossel 3D Printers Upgrades and CNC Machine

I took a chance on a recommendation from a friend on these Iverntech MGN12-H linear rails, and I was very happy with what I saw and received. The linear Rails and Blocks come in a box, wrapped in a bubble wrap tube, and the Liner Rails are sealed in an air tight Bag. Very well packaged, and there was no damage during shipping. (See Photos) What I liked: 1. The packaging. Protective, and air tight to prevent contamination and rust. No rust on any of the 4 I purchased. (Most likely because they know how to package them to prevent rust) 2. The light coating of protective oils to keep the rail and block rust free was just the right amount, it was not all sticky. 3. The precision, and quality of the machining on the rails is excellent. High Quality in my opinion. 4. The precision and high quality of the MGN-H Rail Blocks was outstanding. High Quality in my opinion. 5. Easy to clean the protective oils with just IPA. Soaked them over night in an air tight container, and the were free of protective oils. 6. All 4 linear rails I purchased had all the ball bearings in each block. No missing balls. The balls were of high quality in my opinion. 7. Disassembly of each bearing block was easy, and no issues were found with in the block itself. 8. Tapped threaded holes were clean and chip free. Good quality control there. 9. Very quit operation on the machine. No grinding noises, or flat spots on the balls that would have made them noisy. 10. The high quality of my prints because of the high quality of these Linear Rails. Just outstanding! 11. No having to constantly adjust wheels on my 3D Printer, or change them out due to them being worn out. What I didn't like: NOTHING, I have no complaints what so ever. These are high quality, low price Linear rails. Conclusion: If you want to convert your 3D Printer to linear rails, Then I highly recommend this brand. Inverntech. For $21.00 each, you actually get a high quality product. I have purchased other brands, and they just do not match up to Inverntech's.

These rails really perform pretty amazingly right out of the box. Unlike a lot of the cheaper Hiwin replicas out there, these came nicely oiled and sliding smoothly instead of covered in shipping wax and dragging. That being said, I still did my standard practice of disassembling the rails, cleaning with isopropyl alcohol and re-lubricating with Slick50 Supercharged One Lube and MAN are these things smooth now! While I had them apart, I noticed a few small details that I think are major contributors to these rails performing better than most. First, the quality of the molded plastic parts is much better than expected. There is no flash on any of the edges and they all fit together nicely. Second, and maybe more importantly, the start and end of the tracks that the balls actually roll in have been carefully relieved and tapered so that when the balls enter and exit the tracks there is no hard edge to roll ever and cause any clicking or dragging. These rails are FAR better quality than the offerings of RobotDigg and blow v-slot wheels rolling in 2020 aluminum extrusions out of the water. In my case, an Ultibots D300VS+ delta printer, the swap from v-slot wheels to these linear bearings cause the result of a vase mode test print to go from the ripply appearance of the blue part pictured to the buttery smooth appearance of the black part using the same g-code! Long story short, these are pretty great rails in my experience. Give them a shot!

The best off-brand rails I have ever seen. On disassembly they were clean and well made. The pretensioning was good and uniform the length of the rail. They also were well lubricated and suitable for use right out of the box. However the travel showed moderate sticking. So I replaced the bearing balls with 3/32 silicon nitride balls, and that solved the problem. Probably a couple of balls were slightly over sized. The G5 nitride balls were probably overkill but I thought why mess around.

Little bit of grit out of the box. After a clean and lube it's running smooth though. Has a nice tolerance with no play. Running the x axis on a printer for about three months now and holding up fine.

Two of the 3 I ordered slide smoothly with even the slightest tilt (~15°) of the rail. The 3rd is pretty much unusable it has so much drag. You can hold the rail completely vertical and it still doesn't move on it's own. Upon close inspection, we can see that the precision on the carriage is significantly off so it's off center on the rail causing too much pressure on one side including having the retention wire bottoming out on the inside of the rail channel. I confirmed it's the carriage and not the rail because the other 2 carriages glide just fine on the same rail. Update: Seller/Manufacturer sent me a replacement quickly and without hassle as soon as I notified them of the defect. Replacement glides smoothly and quietly. Frustrating to get a defective part but it happens. At the end of the day, I ended up with 3 perfectly working rails so I'm happy.

If I could give 1/2 a star I would, I ordered 3 of these rails that all shipped from different locations, all 3 rails are different and of different quality. Do they all work yes but I don’t accept that they’re all different that’s just not okay. If you look at the images. Top rail that is plastic on bottom is the BEST and seems to be the highest quality. Middle rail that is split metal on bottom and top is okay, just not buttery smooth like the top. Bottom rail with the unibody is trash… it get jammed up alittle and when I took it off the rail to clean and re-lube it the balls just keep falling out. Then when putting it back on it took me about an hour just trying to keep all the balls in as it slid on…. So when you order I hope you get the medal on top and plastic on bottom.

Arrived in good shape. The carriage block slid fairly easily. I degreased mine with dish soap and water, then used denatured alcohol to get rid of the water. Sprayed with Teflon and let it dry, then used a bit of Super Lube on the rails to distribute over the bearings. Two of these went on an Ender 3 V2 Y-Axis along with a 24 dollar set of brackets. It's only been two weeks, but the bed is much more stable (no give when hand manipulated), and no POM wheels to adjust! No Y-Axis slippage and did I mention no POM wheels to adjust!?

ordered 2 for my 3d printer. one barely moved at all, even when vertical. the other moved and would stick in the middle then move again if you shook it. I was less than enthused. the consensus across the internet was "you get what you pay for" and "cheap Chinese rails wont ever work". still, I didn't want to just give up and return them without trying to see if I could fix them. I tried spraying them with liquid wrench spray lubrication, it helped very very little. I watched a video where someone took apart the rails, soaked them in a solution of alcohol and water, put them back together, and re-greased them. The claim here was that they were "gunked up" from the factory and needed to have better lubricant applied. I tried this and then applied "super lube". This did not work. Finally I found a video of some random kid on youtube. He replace the bearings with https://www.amazon.com/dp/B015RKOZ7G/ and also claimed this changed his barely movable rails to smoothly functioning ones. I was fresh off of watching the previous video about cleaning, and since that had failed, I was skeptical of this, but they were $8, so I figured why not. I just completed the first rail, applied some "super lube", and it now moves with the slightest tilt of one side or the other. (note: if you do this, the part I mentioned above comes with 100 bearings, each side of the carriage needs 33, and there will be a slight gap left over). so, why 3 stars? whats the bottom line? the bottom line is the consensus on the internet is largely correct. there isn't really a middle ground with rails. there's expensive ones that work really really well and come ready to go, and everything else is pretty bad. these however, are super cheap, and can be remedied for not much more of an investment. $8, some patience, a clean, and re-lubrication, and you've got a solid linear rail. if you want a cheap, good solution (albeit with some work involved), these are for you. if you want an out of box solution, be prepared to pay much more.