X axis belt shim to correct the belt path and improve accuracy for ELEGOO Neptune 2

prusaprinters

<p>This is an X-axis belt shim for ELEGOO Neptune 2 series 3D printers.<br>It makes the X belt parallel to the X axis (gantry) and equalizes the nozzle travel scale over the all position on the axis.<br>Therefore, the accuracy of the printing is improved.</p><h4>Installing</h4><p>You can print two shims and install on the toolhead, one is stepper side clamp the other is idler side clamp, under the gantry.</p><figure class="table"><table><tbody><tr><td>Stepper side</td><td>Idler side</td></tr><tr><td><figure class="image"><img src="https://media.printables.com/media/prints/288065/rich_content/5f268c41-ec9a-4c22-8708-ce409c1ae516/install-001-arrow.jpg#%7B%22uuid%22%3A%22c84e6536-97c8-481a-9987-6d99736d64a0%22%2C%22w%22%3A1008%2C%22h%22%3A756%7D"></figure></td><td><figure class="image"><img src="https://media.printables.com/media/prints/288065/rich_content/0cf7b227-5833-4c7c-86c8-567cec19c6be/install-002-arrow.jpg#%7B%22uuid%22%3A%2232492cf6-1217-4e30-bc58-c136114eafd7%22%2C%22w%22%3A1008%2C%22h%22%3A756%7D"></figure></td></tr></tbody></table></figure><h4>The theory</h4><p>If the belt is NOT parallel to the axis: ⊿Xin ≠ ⊿X1 and ⊿X2 &lt; ⊿X1.<br>Therefore, the nozzle travel scale is changed related to the position on the axis.</p><figure class="image"><img src="https://media.printables.com/media/prints/288065/rich_content/3b7dce73-b78f-47a2-ac4c-80de3cf7e593/image-001.png#%7B%22uuid%22%3A%22ddeabe20-df28-4337-b972-8d8a60ec27f2%22%2C%22w%22%3A1190%2C%22h%22%3A515%7D"></figure><p>Correct belt parallel to the axis: ⊿Xin = ⊿X3 and ⊿X4 = ⊿X3.<br>Therefore, the nozzle travel scale is equalized to all positions on the axis.</p><figure class="image"><img src="https://media.printables.com/media/prints/288065/rich_content/64077b09-caac-4db3-b6c6-d0b48f87cd14/image-002.png#%7B%22uuid%22%3A%22856d699f-17cb-4f9b-bc1f-00b7632014ec%22%2C%22w%22%3A1190%2C%22h%22%3A515%7D"></figure><h4>Neptune 2 series stock belt path</h4><p>The stock X belt path of ELEGOO Neptune 2 series is NOT parallel to the X axis.</p><figure class="table"><table><tbody><tr><td>At left end of the gantry, belt inside the gantry</td><td>At left clamp on the toolhead, belt outside the gantry</td></tr><tr><td><figure class="image"><img src="https://media.printables.com/media/prints/288065/rich_content/3cd2844a-613b-4dc8-8eab-2d6e6bdb13f6/stepper-side-001-arrow.jpg#%7B%22uuid%22%3A%22d532f46f-778b-48a0-bd93-145225671148%22%2C%22w%22%3A1008%2C%22h%22%3A756%7D"></figure></td><td><figure class="image"><img src="https://media.printables.com/media/prints/288065/rich_content/a2021e1b-0204-4a67-92cd-4d42d94bb7ff/stepper-side-002-arrow.jpg#%7B%22uuid%22%3A%2224787cb1-2ee8-46da-af7d-f77ae5b5dafd%22%2C%22w%22%3A1008%2C%22h%22%3A756%7D"></figure></td></tr></tbody></table></figure><h4>Correcting belt path of Neptune 2 series</h4><p>It is 5mm off at the stepper side and is 3.8mm off at the idler side.</p><figure class="image"><img src="https://media.printables.com/media/prints/288065/rich_content/bd5578d4-7744-4e79-9cc8-a6957b2fb744/shim-image-001-scale.jpg#%7B%22uuid%22%3A%224f9e5489-30ea-4ca4-8433-e3e9bf434342%22%2C%22w%22%3A1008%2C%22h%22%3A756%7D"></figure><h4>CAD file</h4><p>You can find the cad file on <a href="https://github.com/marbocub/Neptune2-practical-mods/tree/main/X-Axis-Belt-Shim">the project GitHub repository</a>.</p>