Hephestos Idler Pulley

prusaprinters

<p>Idler pulley (containing a B623ZZ bearing), for <a href="https://reprap.org/wiki/Prusa_i3_Hephestos">BQ Prusa i3 Hephestos</a>’s X- and Y-axis belts (6&nbsp;mm GT2).</p><p>I find that this remix of juanjaem’s <a href="https://www.thingiverse.com/thing:1295220">Support for B623ZZ (BQ Prusa I3 Hephestos)</a> fits better (when printed on my Hephestos).</p><p>I think juanjaem’s design is much better than BQ’s <a href="https://cults3d.com/en/3d-model/tool/prusa-i3-hephestos">original</a> which, after several hundred hours’ use on my Hephestos, cracked, loosening its grip on the bearing so that the two halves would move apart and grind loudly against the stationary enclosure.</p><p>I used <a href="https://uk.rs-online.com/web/p/3d-printing-materials/8320232">RS PRO Yellow PLA</a>, which matched the original parts well.</p><h3>Print settings</h3><p><strong>Layer height</strong>: 0.08 mm [to cope with the demanding overhang]<br><strong>Line width</strong>: 0.31 mm [to fit an even number of equal-width lines into the thinnest part, to keep the flow constant and avoid underextrusion on the outer wall]<br><strong>Top/bottom line width</strong>: 0.328 mm [for the smallest gaps in the fewest layers]</p><p><strong>Wall line count</strong>: 2<br><strong>Outer before inner walls</strong>: no [for the overhang]<br><strong>Z-seam alignment</strong>: Random [to avoid a seam, which would stretch the belt very slightly more when engaged and causing a (possibly imperceptible) pattern on prints]</p><p><strong>Bottom layers</strong>: 999<br><strong>Top/bottom pattern</strong>: Concentric</p><p><strong>Combing mode</strong>: All [to avoid travels across the hole which might leave threads which could possibly find their way into the bearing]</p><p><strong>Supports</strong>: none</p><h3>How I designed this</h3><p>In Tinkercad. &nbsp;<a href="https://www.tinkercad.com/things/ldtzN6wKzRS">Edit it online.</a></p><p>&nbsp;</p><h3>This remix is based on</h3><figure class="image image-style-align-left"><img src="https://media.prusaprinters.org/media/prints/122216/rich_content/98db1074-c935-4711-9a55-3487ccb78a61/4f0f2af91275a1b5031d560f93705693_preview_featured-60.png#%7B%22uuid%22%3A%2238d96595-3bb0-4129-920f-9c3183df91f8%22%2C%22w%22%3A80%2C%22h%22%3A60%7D"></figure><p><br><a href="https://www.thingiverse.com/thing:1295220"><strong>Support for B623ZZ (BQ Prusa I3 Hephestos)</strong></a><br>by <a href="https://www.thingiverse.com/juanjaem">juanjaem</a></p>