fix that drift y or x axis on your simple!
I'm not sure if this will be of interest to anyone or not but here is a tensioner for the string drive on the simple.
print out, multiples work better, drill out the hole and screw in a m3 or 4-40 screw. Tapping is not necessary. Tie the string around the screw head and tighten. This is probably self explanatory by the pictures.
it is a press fit onto the plywood.
you loose aproximately .25" travel when used on the x axis, my bot couldnt get there anyway.