Simon's adjustable Y motor bracket

Redesigned Y motor bracket for the Mendel Prusa 3D printer. Features top tensioner bolt to make belt tensioning easier, and it works.
Modelled in heeksCad. It is intended to work with Y-carriage I designed and which doesn't have a built-in tensioner.
The photo below with it on the end of my Mendel Prusa is to show how it fits with the rails and is not where it goes on the machine :)
Inspired by two earlier designs both of which are good ideas but needed further development - this places the adjuster on the top rail where it is easy to access and the whole thing fits better.