Elegoo Neptune 4 tensioner

This is a 3-piece belt tensioner for the z-axis. 

With 5mm of adjustment and carefully measured distances for the belt slop of my printer, it allows for keeping the belt tight, without fiddling with the geometry of the gantry.

It mounts in between the frame and the spool holder, using the stock bolts. The pulley is held by and is spinning about an m3 bolt of 12mm in length. The spacer is held by another 5mm m3 bolt but has enough surface to be glued with CA glue instead.

In case this design does not provide enough tension, or is too tight for your cause, a pulley of a different size might be needed. I'll be glad to address your issue, so do not hesitate to leave a comment.

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