Due to the Kobra 2 Max machine using two dual-axis core rails for the Y-axis, if you only need to replace one rail, please refer to the relevant sections based on your specific situation.
M2.0/2.5/3.0/4.0 Allen wrench
Before starting the replacement of the Y-axis rails, ensure that you have a relatively spacious workbench or table for disassembly. Most importantly, turn off the machine and disconnect the power to ensure safe operation.
Using an M2.5 Allen wrench, remove the 4 screws that secure the cover of the heated bed control board, then set the cover aside. Place the removed screws in a container and label their positions.
Use an M2.5 Allen wrench to remove the 6 screws that secure the rails to the base. Place these screws in a container and label their positions.
①Turn counterclockwise to remove the red knobs on the two belt tensioners of the Y-axis.
②Move the heated bed to the front-most position, then use a wrench or another tool to release the belt buckle from the left rail by moving it to the right and then forward. Do the same for the right rail by moving the buckle to the left and then forward.
③Use an M2.0 Allen wrench to remove the 2 screws on each side of each tensioner.
④Remove the tensioners and then take the belts out of the pulleys.
Use an M3.0 Allen wrench to remove the 6 screws that secure the Y-axis motor assembly. Since the Y-axis motor assembly is connected with wires, place it within the range of wire movement for reinstallation later.
Pull the belts out of the rails. If the copper buckles interfere with the process, adjust their positions slightly.
Gently slide the heated bed out of the Y-axis rails towards the back of the machine. Since the wires for the heated bed are not removed, keep the heated bed within the range of wire movement for reinstallation later.
Use an M3.0 Allen wrench to remove the 12 screws that secure the Y-axis rails (both of them). Remove as many screws as needed based on the number of rails to be replaced.
①Note that the holes at the bottom of the left and right Y-axis rails are different. Be extra careful when installing the new rails.
②Once the rail positions are confirmed, align them with the screw holes on the base, and using the M4.0 Allen wrench, pre-lock the screws onto the base.
③Align the rear end of the rail to the base to ensure it forms a parallel line, then tighten the screws at the rear end first and then the others.
①Ensure that the copper buckles on the heated bed are not detached. If they are, adjust their positions.
②Thread the buckles at the other end through the rails to the front of the machine.
Slide the heated bed from the rear into the rails. If you encounter any installation obstacles, use an open-end wrench to adjust the hexagonal eccentric pillars at the bottom of the heated bed.
First, pre-lock the 2 screws next to the motor with an M3.0 Allen wrench, then pre-lock the other 4 screws. After pre-locking, adjust the two iron bearing plates on both sides towards the direction of the synchronous pulley, and finally tighten all the screws.
①Remove the pulleys from the Y-axis tensioners and pass the front-end belt buckle around the pulley. Ensure that the belt teeth align with the pulley teeth.
②Move the heated bed to the front-most position and use a wrench or other tool to move the left belt buckle to the left rail by moving it backward and then to the left. Do the same for the right belt buckle by moving it backward and then to the right.
③Install the Y-axis tensioner housing, remove the screws from the housing that were removed earlier, and use an M2.0 Allen wrench to screw them into the screw holes on the left and right sides of the housing.
④Turn the red knobs on the two belt tensioners clockwise to install them onto the Y-axis tensioner housing.
Use the screws that were removed earlier to secure the bottom of the base rails with an M2.5 Allen wrench.
Use the screws that were removed earlier to secure the cover of the heated bed control board with an M2.5 Allen wrench.
Turn the Y-axis tensioner knobs clockwise to make the belts as tight as possible, and then turn them counterclockwise for two full turns.
Use an open-end wrench to adjust the hexagonal eccentric pillar on the right side of the heated bed until the bed can slide smoothly and there is no noticeable wobbling when moving the bed left and right.
For more detailed visual instructions, you can refer to the "Kobra 2 Leveling Guide" video from the provided link, starting at 57 seconds into the video. Follow the video's guidance for adjustments to ensure smooth bed movement and stability.
After replacing the Y-axis guide rail, On the main interface, click "Tools"icon ➜ "Control"icon ➜ "Module Calibration" ➜ "Position Calibration." The machine will automatically probe and stop near the calibration module. Use the interface's distance units and X/Y axis movement directions to adjust the nozzle to the center position of the calibration module. Once done, click "Save" and then perform the automatic leveling process again and manually adjust the Z-axis offset during printing to avoid printing in the air.
We recommend checking the Y-axis dual-axis guide rails every month to ensure they are clean and free of foreign objects. This helps maintain the smooth operation of the guide rails and ensures the stability and accuracy of the machine.
Turn off the machine and disconnect the power. Using a lint-free cloth or a soft brush, check if there is dust, debris, or other foreign objects adhering to the rail surface. If there are any, gently remove them. Check the smoothness of the rail's movement path, ensuring there is no sticking or resistance. Use your hand to gently move the Y-axis and observe the motion of the rails.
If you find a significant amount of dust or debris on the rails, you can follow these cleaning steps:
Use an air gun or a hairdryer to blow away the dust on the rail surface. If using an air gun, lightly press the trigger, being careful not to blow excessively to avoid blowing dust into other components or damaging electronic parts.
Apply a small amount of lubricating grease to the core on both sides of the Y-axis rails. Then, gently move the corresponding print head module and heated bed to distribute the grease evenly on the rails.
After completing the maintenance, gently push and pull the heated bed and print head module by hand to check for any sticking or wobbling. If present, refer to the leveling guide of the Kobra 2 video to readjust the hexagonal eccentric spacers. (Insert leveling guide video link here)
Reconnect the power and turn on the machine. Perform a test print run, observing smooth movement of the Y-axis without any abnormal resistance or noise. Ensure the cleanliness and proper functioning of the rails. If you still have any issues, it is recommended that you create an after-sales work order to feed back the process and results of the previous inspection to the after-sales engineer. After-sales engineers will help you solve the problem.
If the above steps do not provide assistance or if you encounter any other issues during subsequent use, we recommend that you create a support ticket. The after-sales engineers will assist you in finding a solution to the problem(Reply time :1 working day)
Please click this link to submit your ticket: