For Neptune 3 MAX installation, please skip steps 5 and 17.
1. Remove the platform plate and unscrew the hand-tightened nuts. Keep them for later use. 
2. Remove the screws fixing the heated bed in the center and take off the heated bed plate. Set aside the springs and spacers for later use. 
3. Unscrew the screws on the synchronous belt fixing plate. Keep the screws for later use. 
4. Remove the rear cover of the Y-axis and set it aside. 
5. Carefully unplug the Y-axis accelerometer connector.
6. Take out the Y-axis support plate from the aluminum profile.
Note: Keep the screw that touches the limit switch in its original state.
7. Remove the six POM wheels from the support plate.
8. Attach the M4*8 screws and M4 T-nuts to the long bracket. (Do not fully tighten; screw in just two turns.)
9. Fix the long bracket onto the aluminum profile (it is recommended to install the left side first).
1. Front-to-back alignment: The long bracket should be 25 mm from the rear end of the machine, or align the notch on the long beam with the screw position on the machine as a reference.
2. Vertical alignment: The bottom of the long beam should rest against the machine casing, with the top surface level with the aluminum profile of the machine.
10. Secure the Y-axis rear cover onto the aluminum profile.
11. Use M3*5 screws to attach the linear rail onto the long bracket. Do not fully tighten the screws yet. After completing step 15, slide the support plate back and forth a few times, then tighten the screws.
12. Use M3*8 screws to attach the short bracket onto the slider.
13. Determine whether your machine is the latest version or an older version (refer to the image for reference).
14. For the latest version:
1. Use the aluminum spacer provided in the "spares" and place it on the short bracket.
2. Then place the on top of the aluminum spacer.
3. For older versions: Place the silicone gasket directly onto the short bracket without using the aluminum spacer.
15. Use M5*14 screws to secure the support plate onto the mounting plate. Ensure the support plate is oriented correctly (the accelerometer should be positioned at the rear left of the machine). Start by screwing into the two small holes on the slider plate before attaching the other screws.
16. Tighten the synchronous belt fixing plate.
17. Reconnect the accelerometer cable.
18. Reinstall the heated bed plate onto the slider plate. Ensure the spacers and springs are not missed.
19. Attach the hand-tightened nuts onto the fixing screws of the heated bed.
20.Place the platform plate back onto the heated bed plate.
The upgrade is complete!
Please re-level the machine (refer to the official guide) before printing. Thank you!
Thank you for choosing our product to upgrade your 3D printer. If you encounter any issues during installation or use, have new ideas, or need assistance with anything else, feel free to contact us at any time.
Our current contact methods are:
· Email: xixiranran1419@gmail.com, tbstron3d@gmail.com
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