Geeetech

I would recommend a longer screw and a spring and washer under the wing nut of both the X and Y axis tensioners...just a observasion. you really don't want to have the belt stretch...as it changes the length of the belt...distorting you print. causes jumping if to slack and stiffness in the movement of the bed when too tight...a spring...would absorb any shock and give a more consistent tension. just saying. works for me.

if you put a spring there, as it will draw and shrink, will it affect the accuracy?

Not really..it was far less than without...any way I upgraded to the aluminum guide and bearing set...it stopped the premature belt wear and hence any stretching...and I got rid of the spring...and the blue belt holder and made a metal one...