ToM APB Belt Tensioner (Q56217)

The goal of this creation is to place the ToM APB (Automated Build Platform) belt under high tension, so it acts much like a solid plate surface (emulating the HBP (Heated Build Platform) surface) while retaining the ejection capabilities of the APB. This is a lever arm that stretches out your APB belt. Under high tension, the belt resists flexing up at sides due to warping stresses during cooling and sits flat on the heating board before printing. The arm attaches to the sides of the roller bar, and friction is kept to a minimum by bearings at the point of contact. The lever arm tension is set by manipulating a screw. This bolts onto the stock APB, requiring only two bearings and two short m3 screws to be purchased. Misc M3 screws will allow this to be bolted onto the ABP. However, proper-length countersunk head 10mm to 15mm M3 screws should be used for the tension-setting screws in order to avoid their sticking out and running into the z-stage bars during homing and printing. I recommend using a sturdy belt to handle high tension (such as Tunell's Steel Conveyor Belt for ABP. http://www.thingiverse.com/thing:9127). Using this tensioner and a kapton-covered steel APB belt, I have been able to achieve quality near that of the Kapton-covered Aluminum HBP while preserving the ability to queue up multiple parts and remotely print. It's not perfect, but I'd say it's pretty darn good.