MPCNC belt tensioner for strong belt

First, thanks to Allted for greatest CNC design - MPCNC and to DodgeDerek for original belt tensioner. This is a remix of tensioner for metalized plastic belt, which is slightly thicker than common rubber one.

Also, this tensioner do not need additional spacers on rollers and work for original MPCNC design. Tensioner was designed by slicing mesh and I can send source files to anyone concerned.