Tronxy/3DCStar P802 X-Axis Belt Tensioner by wypoon

Last crawled date: 3 years ago

The Tronxy P802M X-Axis end-carriage is not a 'through' design, and traditional Anet A8 belt-tensioners, which rely on looping the belt past the end of the right end-carriage, will not work on it.
This compact design simply snaps on to the X-axis rail by the right carriage which:
adds more tension to your x-axis belt (e.g. when it stretches due to aging), and
has the added benefit of making the x-axis belt loop more run more 'parallel' to each other (the Tronxy uses a much larger bearing than the diameter of the stepper pinion gear).
Assembly:
Print all three parts and perform any clean-up or sanding required. Use a Q-Tip to clean the outside and inside cylindrical faces of the bearing with alcohol to remove any grease/oil.
Test fit the pulley wheel cap (WheelB) to the pulley wheel (WheelA). Make sure the cap's groove is clear of debris and that the cap fits snug and the two circular guard flanges are parallel to each other.
Lightly coat the inside barrel of the pulley wheel with CA glue (be sure to wipe off any excess) and press a 5x11x4mm bearing into the wheel. Once flush in the wheel, use a dowel (a X-acto knife holder also works) that is >4mm to push the bearing all the way until it's completely seated within the pulley.
Lightly coat the i. rim of the pulley wheel (where it contacts the wheel cap), as well the ii. groove of the wheel cap with CA, and press the cap tightly onto the pulley. Let it set overnight.
Use a small butane torch (or cigarette-lighter) to heat up just the nub of the tensioner. Be very gentle (very quickly brush the flame across the nub 2-3x). Press the assembled pulley-wheel onto the nub. Make sure it's seated fully and while the nub is softened, adjust the plane of the pulley so that that it's straight and square and will not wobble as the pulley is rotated on the post.
Once the nub has cooled down, remove the pulley. Coat the cylindrical face of the nub with CA glue (be absolutely sure to wipe off any excess) and re-insert the pulley. Let it set overnight.