Motorized Laser table remix - spacer inserts for 688z idler-bearings and corrected script

When building https://www.thingiverse.com/thing:4066979 from @mumpitz_82 I ran into two issues:

1. I did not find parts or a desription on how to mount working idlers on the motormount
2. the sketch didn't work because one input pin was incorrectly defined and the steppulse forming was also not correct (missing the delay after low-pulse).

I have added spacers (print two sets) and insert a small and a big spacer in a 688z bearing. Then mount the assembly with the big spacer facing up into the motormount using a 20mm M3 Screw and a hexnut. Repat with the second idler. Then fiddle the belt in and properly tension it. Enjoy a smooth ride!

Parts needed in addition to the original: two 688z bearings, two M3x20 and two hexnuts M3

OpenSCAD code for the spacers: module spacer()

{

difference()

{union()

{

cylinder(d=10,h=1.8,center=false);

cylinder(d=7.8,h=4.4,center=false);

};

cylinder(d=3.5, h=20,center=false);

}

};

module spacer2()

{

difference()

{union()

{

cylinder(d=18,h=1.8,center=false);

cylinder(d=7.8,h=4.4,center=false);

};

cylinder(d=3.5, h=20,center=false);

}

};

translate([50,50,0]) spacer();

translate([70,70,0]) spacer2();

Enjoy

Armin

Category: DIY