Replace X and Y axis tensioning mechanisms

The standard tensioning mechanisms on the A8 plus are functional, but leave a lot to be desired. 

I also discovered that the 3mm ID idler bearings which are used are very poor, as are all of the replacements which I tried. The standard ones are also smooth, rather than toothed. The toothed idlers are really more appropriate for running on the toothed side of the belt as these do. 

I went through numerous iterations of design to try to find the optimum solution and I believe that the variant using captive clamping and toothed bearings with 5mm ID works well. 

My designs both use toothed pathways for the loose ends of the belts to effectively hold them in place. This keeps the belt path straight and allows for easy insertion and removal. 
Toothed Belt Clamps

Follow the links below to see the changes for each axis

X Axis Modifications


If you are planning to use my designs for limit switch mounts, this includes a modified Y axis belt mounting bracket and you should bear this in mind when considering which to print

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