MMU Air Buffer V1

prusaprinters

<h3>Why?</h3><p>I was tired of failures due to extra resistance and odd angles for the PTFE tubes on my MMU so I created the Air Buffer V1.</p><p>I was inspired by this “air buffer”: <a href="https://www.prusaprinters.org/prints/30793-mmu-air-buffer-auto-rewinder">https://www.prusaprinters.org/prints/30793-mmu-air-buffer-auto-rewinder</a></p><h3>How To Achieve Success!</h3><ol><li>Upgrade the external PTFE tubes to 4mm outside diameter, 3mm inside diameter. Anything from the filament spool to the MMU and from the MMU to the extruder head. &nbsp;I needed two orders of the following:<ol><li><a href="https://www.amazon.com/gp/product/B07B8CK8L9/ref=ppx_yo_dt_b_asin_title_o08_s00?ie=UTF8&amp;th=1">https://www.amazon.com/gp/product/B07B8CK8L9/ref=ppx_yo_dt_b_asin_title_o08_s00?ie=UTF8&amp;th=1</a></li><li><strong>NOTE:</strong> this tubing isn't high quality stuff, you can visually see differences in the thickness of the tubes, but it seems to work fine in this application.</li></ol></li><li>Upgrade the MMU's rear PTFE infeed holder to prevent kinks and allow smooth transition of filament into the MMU. &nbsp;I used this:<ol><li><a href="https://www.prusaprinters.org/prints/6605-prusa-mmu2-ptfe-holder-m10-passthrough-adapter">https://www.prusaprinters.org/prints/6605-prusa-mmu2-ptfe-holder-m10-passthrough-adapter</a></li><li>You may need to order the PC4-M10 male connectors if you don't have them on-hand:<ol><li><a href="https://www.amazon.com/gp/product/B01KHN1HWY/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&amp;psc=1">https://www.amazon.com/gp/product/B01KHN1HWY/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&amp;psc=1</a></li></ol></li></ol></li></ol><h3>Other Items Not Created by Me:</h3><ol><li>This is the wall mount I'm currently using to hold the filament spools. &nbsp;There is nothing special about this, but I had them printed so I used them (they are lengthy prints). &nbsp;But it is what I used to mount my air buffer to, so the air buffer is specifically designed to fit this:<ol><li><a href="https://www.thingiverse.com/thing:4001586">https://www.thingiverse.com/thing:4001586</a></li></ol></li><li>Nuts and bolts<ol><li>I went to Lowe's and bought some hardware a long time ago so I don't have specifics. &nbsp;Here are the measurements:<ol><li>Shaft length: 37.5MM</li><li>Shaft diameter: 12.55mm</li><li>Plus the nuts to match</li></ol></li></ol></li></ol><h3>The Air Buffer:</h3><ol><li>There are three printed parts to my MMU buffer solution:<ol><li>wallMountFilamentAirBuffer.stl</li><li>airBufferBoltHolder.stl</li><li>filamentPassthrough.stl</li></ol></li><li>Printing:<ol><li>No Supports</li><li>Printed in PETG (PLA should be fine)</li><li>Layer height: 0.2</li></ol></li><li>Assembly:<ol><li>Glue the offset part of the wallMountFilamentAirBuffer to the wall mount. &nbsp;Lightly sand both parts and use super glue:<ol><li><img class="image_resized" style="width:27.57%;" src="https://media.prusaprinters.org/media/prints/117392/rich_content/8573c245-7b26-40e2-98d8-715702fa819a/img-4255.jpg#%7B%22uuid%22%3A%22fdb005e5-f25c-471c-aedd-9ee6e5fb66fd%22%2C%22w%22%3A3024%2C%22h%22%3A4032%7D"></li></ol></li><li>Add the PC4-M10 Male pass-through connectors at the front.&nbsp; Note, the print is non-threaded so the hardware will cut the thread, there is a 13 degree angle to the PC4-M10 hole.<ol><li><img class="image_resized" style="width:28.7%;" src="https://media.prusaprinters.org/media/prints/117392/rich_content/d384fa3c-5789-4dbe-8516-8586f2c5a61d/img-4257.jpg#%7B%22uuid%22%3A%2245bbce76-649a-435a-b7f0-e85b1dfa4bd0%22%2C%22w%22%3A3024%2C%22h%22%3A4032%7D"></li></ol></li><li>Insert a small piece of 4mm O.D. 3mm I.D. PTFE tube to feed the filament from the spool through the support, I used hot glue to hold in place:<ol><li><img class="image_resized" style="width:29.04%;" src="https://media.prusaprinters.org/media/prints/117392/rich_content/0b146f49-c687-45ee-aaa9-899181c89fcf/img-4256.jpg#%7B%22uuid%22%3A%22683ba5a6-c971-40da-9184-a2660907965d%22%2C%22w%22%3A3024%2C%22h%22%3A4032%7D"></li></ol></li><li>Create the bolt holder filament weights:<ol><li>Attach the two parts (airBufferBoltHolder.stl, filamentPassthrough.stl) with super glue after the filament pass-through feet are inserted into the bolt holder. &nbsp;Note I friction fit a small section of 4mm O.D. 3mm I.D. PTFE tube into the hole at the top of the filament pass-through:<ol><li><img class="image_resized" style="width:33.43%;" src="https://media.prusaprinters.org/media/prints/117392/rich_content/f22c2583-72e7-44dc-a675-3d89903ab51c/img-4251.jpg#%7B%22uuid%22%3A%22290e5484-9619-43ca-8ff4-8bfcc2064e3f%22%2C%22w%22%3A3024%2C%22h%22%3A4032%7D"></li></ol></li></ol></li></ol></li></ol><p>&nbsp;</p><p>&nbsp;</p>