Please check out version 3:
I am switching the X Axis on my CobbleBot from a vertical orientation to a horizontal orientation and moving the X stepper motor and the X idler pulley on top of the gantry instead of the side. This should give a far more secure connection and prevent the belt tension from twisting the stepper and the idler. Please note that if you cut your GT2 timing belt supplied by CobbleBot to fit their design you will need to get a new one. If you did not cut it, you should have just enough for this design to work.
The X Axis Stepper Mount has notches that will fit down into the 2020 V slot rail and help align the T nuts for easier attachment. There are two mount points on the back for attaching a 40mm fan to cool the stepper as well.
The X Axis Idler Mount also has notches that will fit down into the 2020 V slot rail and help align the T nuts for easier attachment. If I have done the math correctly there should be enough room for an idler pulley from OpenBuild to fit (http://openbuildspartstore.com/smooth-idler-pulley-wheel/) (currently waiting for the set I ordered to arrive). You can also just use 2x 625 bearings with some washers (currently pictured) but you will need to make sure everything is aligned perfectly for the belt not to wonder off to one side.
The X Axis Belt Y Attachment also has notches that will fit down into the 2020 V slot rail and help align the T nut for easier attachment. There are also attachment holes on the sides so this can be attached on three different sides of the 2020 rail. The two side holes do not have the alignment notches as I wanted this to be something that could be added without having to take the whole Y gantry apart.
- Cut the sides down on the Idler Mount so it can get closer to the rail.
- Adjust models for better tolerances once my printer is more accurate.
At present I have the holes on the larger side as I am having issues meeting tolerances on the X. I am including the SketchUp files so you can make any adjustments you may need.