This thing is WIP and there are currently no building instructions! The parts are for the 25mm version of the MPCNC.
By interlocking a belt with a second belt it is possible to reduce the length of the tensioned belt and therefore reduce stretching. The parts were designed for a 15mm wide belt, but other sizes should work as well.
For more information check out my build series: https://youtu.be/IjwD5smOt38
Parts you need:
4x 20x20x3 angle iron (same length as your x-/y-conduit)
16x M6-75mm screws (DIN 912) + nuts
8x M4-20mm screws (type doesn't matter) + nuts
8-16x M3-30mm (depending on your amount of tensioners)
16-24x additional 608 bearings (depending on your amount of tensioners)
You still have to print all parts from the original MPCNC, EXCEPT:
Everything that has a "Corner" in its name
Roller and RollerM are modified because there is no space for a nut below the angle iron. So you have to tap the frontal bearing hole and also use a shorter screw.
1-19-2019: Removed countersunk on Corner_Top, M6 screw length adjusted to 75mm