Updated 4/27/2020 (details at bottom of summary) WOULD LOVE TO SEE MORE MAKES, PLEASE POST A MAKE IF YOU DO GO THROUGH WITH THIS. DISCLAIMER: my printer has been heavily modified and there may be things that won't work on a stock CR-10 or Tevo Tornado. Please plan ahead make sure you cover all your bases. This mod probably isn't for people new to 3d printing. This is a set made to replace your X and Z axis with linear rails. I did this on a CR-10 but I'm sure it can be adapter to many 2020-based cartesian printe. Just get the appropriate length rails. requires: 1 x 400mm rail with a mgn12h carriage 2 x 500mm rails with mgn12c carriage -(or 2 x 500mm rails with mgn12H carriage. 2 x Delrin Anti-Backlash Silent Nut for 8mm T8x8 Lead Screw Trapezoidal ACME Link to item on manufacturer webpage: -(or use the adapter "Lead Screw POM Nut Adapter " it's untested but should work). Many M3 and M4 screws and nuts. The carriage is modular but I've only made an adapter for a Titan Aero. It's should not be hard to attach just about anything to it since it's just 6 screws. More pictures of this setup ( Lastly I want to reiterated that I can't guarantee everything will work on your CR-10 or Tevo Tornado. My printer has been heavily modified. One example off the top of my head, You'll have to figure out endstops on your own, I'm using a Duet Wifi for seor-less homing. There may be far more things that you'll have to figure out but I wanted to share all the work I've done. The idler mount to idler clearance is pretty tight. I recommend using sand paper to smooth it out until it slides easily smoothly and doesn't get stuck. [UPDATE] Created a purpose built idleteioner to go with this. [UPDATE2] added "" with a properly sized recess for the stepper collar to fit into. [UPDATE3] Added a brace/guard around the front left on the X axis. Also added a couple rende. [UPDATE4] Added an option to use MGN12H for the Z direction itead of MGN12C. [UPDATE5] Added "Lead Screw bearing " it was difficult to print in PETG as one piece so I split it in two pieces. This veion prevents the lead-screw and bearing from rattling around while printing. [UPDATE6] Added POM nut adapte, 18mm hole spacing and 16mm hole spacing. This should allow you to skip buying the one I listed. [UPDATE7] Added x-idler which fixes some tight clearance issues. [UPDATE8] Added step files per request (they may be out of date compared to some of the updated parts, did not have time to upload each and every piece so I used an old assembled veion, hopefully that enough to help some people who needed to do mods.) [UPDATE9] Added a compact X carriage that I specifically needed for an aluminum mount for the titan aero. The compact mount is a pretty rough design but I tested it and it works. -Aluminum mount: [UPDATE10] Added a optional pillow block mount for the Z lead screws. Unfortunately with the current design you will probably only be able to use this on top only and not both sides of screw. STL name: Pillow_Block_Z-Idler_v1.stl Link for pillow block: (option: KFL08-8MM) Requires some M5 screws, nuts and T-nuts. [UPDATE11 - 4/27/2020] New beefy X Idler! So my second printer is a Voron 2.2 and I really liked how overkill their idle were so I modifed one to use with my X-axis. I'll also post something for the Y axis eventually but it need a bit more work. Check out voron if you're interested in a extremely nice fully enclosed FDM printer: This idler will require a few things: 1X - 5mm diameter metal shaft (30mm long) 2X - F6952 bearings 1X - GT2 20Tooth Pulley (5mm ID) M5 washe for alignment Some m3 screws, nuts and washe. Important FYI - I only printed this new idler in ABS and ABS I don't know of PETG or PLA will work. ABS also has a bit of shrink (about half a percent) , so parts may not fit as intended with other materials unless scaled down. eSUN ABS would let you print this on an open printer.