CoreXY Manual Z-Lock (TronXY X5SA)

thingiverse

This is a manual Z-axis lock mechanism I designed for my new TronXY X5SA-400 Pro, but it will work for most coreXY printers. It allows you to keep the bed alignment between prints. This provides a basic, manual way to solve the bed leveling problem on coreXY printers. (if you don't know what this problem is, you probably don't have a coreXY printer :D ). PRINTING 1) Print two sets of the body and latch, one for each Z-Axis leadscrew. 0.3 mm layer height with PLA worked fine for me. Print the 'z-lock-body upside down to avoid overhangs. ABS and PETG will work fine too. INSTALLATION 1) Install the M3 nut in the body, spread the fingers of the unit to get around the leadscrew, and then drop it over the flexible coupling 2) Tighten the body down onto the NEMA17 motor with some M3 screws, position the latch in the slot on the arm of the body and insert the M3 tension adjuster screw. Get the tension adjuster screw in and pull the M3 nut back to seat into the arm. 3) Lock the latch by pushing it over the detent, and adjust the tension adjuster screw so that when the latch is in the locked position, the flexible couple coupling is held reasonably tightly. You do not need a lot of force here. SETUP 1) Adjust your bed leveling screws so that they are approximately all equal height (if your bed is close to level, you can probably skip this) 2) With motors off (printer off), manually lift the bed to approx 1 mm below the nozzle (by turning the stepper motors with your fingers). Try to get it approximately level (within 1mm) 3) Now lock both axes 4) You might want to unplug your USB cable for the next step. When you move the carriage manually, the motors generate a back-EMF, which can send power back up the USB port and crash your computer. I know this because it happened to me twice. 5) Start manually moving the print carriage in the X axis (left & right), and observe the change in gap between the nozzle and the bed. If the difference in gap when the carriage is on the left or right is large (greater than 1mm), unlock the appropriate motor, and adjust as close as you can to get the bed parallel, and then lock that motor again. 6) Repeat for the Y-axis. Move the carriage in the Y axis, and check for the gap between the nozzle and the bed. Adjust the bed leveling screws to get the bed parallel in the Y-axis to the carriage. in the average. Notes for steps 5 & 6: If your bed is like mine, there will be low and high spots, especially if it is cold. Try to average it out so that you get the best average alignment. Or do this when the bed is hot. USAGE 1) When you switch the printer on, connect to your printer and wait for the motors to switch on *before* unlocking *both* locks. DO NOT attempt any moves or homing before unlocking. If you have a script that runs on turn on, that causes an immediate homing, disable it. Add it to your print startup g-code. If the motors do not switch on automatically,, you can issue an M17 in the console. This will turn the stepper motors on. (tested with Marlin Firmware). Now you can unlock both axes. 2) After the print stops, but *before* the motors switch off, engage the locks on *both* axes. 3) do steps 1 and 3 for every print. Your coreXY Z-Leveling problems just went away. (mostly :D) I will add a video of the steps shortly. I hope you found this useful.