About this 3D model
A simple T2.5 Belt tensioner, this requires a pair of M4 nuts, and long bolts, I used hex driver headed, simply print, push belt through hole, silde in a pice of rod, 4 - 6 mm Diameter. NOTE: you will need to drill 2 4mm holes 20mm apart,for the bolts. Tension and have betterprints !!