Sintron i3 X Axis Tension kit

thingiverse

The X gantry right side bearings on the Sintron i3 clone are directly linked to the X gantry itself. Meanwhile, the X-axis tension is solely controlled by how you secure the belt into the X carriage. If you prefer a higher belt tension, it has a tendency to pull the right side gantry along the rods, causing your Z axis rods to curve in and bind up. I designed this setup to replace the existing configuration and take full advantage of the extra 10mm of X rod length in my kit. After installing these components, you will be able to run the X tension at a much higher level, and the X gantry right side will be free to float and self-adjust for minimal friction on the Z axis. To assemble: Insert two flanged 5 x 10 x 4 bearings into the idler holder as shown. You'll need an M5 bolt and nut to serve as a shaft. Next, insert an M4 "nylock" locking nut into the nut capture cavity in the end of the idler holder. Place the idler holder in the right side gantry as indicated. Position the tension brace over the rods as shown. Run a long (at least 30mm, 40mm is ideal) M4 socket-head cap screw (or pan head) and M4 fender washer through the larger hole in the brace and into the idler holder. Tighten the belt tension. Your X-axis belt tension is now adjustable by means of the M4 bolt, and will no longer cause binding of your Z-axis. OPTIONAL: Run an M3 SHCS and fender washer into the two 3mm holes on the bracket. This should significantly increase the strength of the bracket and prevent delamination.