Anet A2 and TEVO Tarantula MGN15 linear rail Y axis mod

thingiverse

This is a complete package of printed parts required for upgrading the Y axis on Anet A2/+ with MGN15 linear rail. The belt tensioner part was remixed from Olev's design (https://www.thingiverse.com/thing:2157807) to incorporate a parallel belt when using MGN15 rail on the Y axis, and also serves as a mechanical stop for the rail carrier. For added strength, it features fatter sides that allow for the use of M5 T-nuts and screws for mounting on the aluminum 2040 profile. The only piece missing is the tensioner screw, which remains unchanged from Olev's original design and can be sourced separately. The motor mount was recreated from the original Anet acrylic mount, modified to accommodate a parallel belt for MGN15 rail use. For optimal results, I recommend printing the tensioner parts with 70% infill, but 40% may suffice. In contrast, the motor mount requires 100% infill due to its one-sided mounting design and need for stability against flexing. During my experimentation, I discovered that while the linear rail and original acrylic carrier function adequately with PLA printing, they experience issues with ABS and elevated bed temperatures (around 100°C). The small rail carriage creates a leveraged effect, causing springs and heat to cause the acrylic bed carrier to flex and make leveling challenging. Furthermore, this flexing changes as temperature fluctuates continuously, making it difficult to achieve and maintain proper leveling. Replacing the acrylic bed carriage with a sturdy aluminum one (3mm thickness is ideal) completely resolves these issues, ensuring a smooth and level printing experience.