New NoName belt routing with front belt tensioning and rear motor mounts

My NoName has already seen many upgrades and redesigns and is still evolving.

To get some more build space especially in the front I wanted to have the A/B motors mounted in the back and have the belt tensioning mechanism removed from the print head, what led to this new belt routing and mount design.

It should even allow more travel in Z now when using my triple-Z mod: https://www.thingiverse.com/thing:6496524

It is still compatible with the original or my designed print heads/X-carrier though the belt spanners might need to be changed to allow parallel belt routing towards the print head. But you can even keep the original belts and reuse other parts - see parts list.

My main goal of the motor mount design was to mostly use the screws that bolt the motor to the respective mount for attaching pulleys/ball bearings to save space. However this was not fully practicable and required an additonal bearing stack to maintain the correct belt distance towards the front. Those additional stacks use seperate screws (should work with the motor scews too).

<h5>BOM:</h5>

• Screws motor to mount: 8x M3x30
• Screws idler to motor mount: 2x M3x27 (cut down from M3x30 or try M3x30)
• Screws motor mount to frame: 4x M3x12(10)
• Screws motor mount to frame: 4x M3x20(18)
• Screws tensioning mount to frame: 4x M3x8
• Screws tensioning clamp to mount: 2x M3x20
• Hardened steel pin tensioning idler pulley: 2x 3x18 mm
• Tensioning idler pulley: 2x Powge GT2 16T (with teeth!) 6mm 3mm bore; tread diameter: 9,6 mm; total height: 9 mm
• Ball bearings: 6x F685ZZ (reuse from original parts)
• Ball bearings: 6x MF115ZZ (reuse from original parts)
• Threaded heat inserts: 2x M3 height: 5 mm (used in "belt_spanner_x2.step")

<h5>Special notes</h5>

The "pulley_pin_adapter_x6.step" parts sit in the bore of the ball bearing stacks (1x F685ZZ + 1x MF115ZZ).

For the toothed pulleys on the A/B motors please use ones with a not too big base as it might collide with the belts later. Maximum diameter should be 16 mm!

For belt routing please check the attached photos.

The tensioning clamps have two differently sized holes in their arms: one with 3 mm to insert the hardened steel pin and a smaller hole to push the steel pin out again for maintenance. Install the tensioning clamps with that smaller hole on the bottom so the steel pin can't fall out if it might become loose!