PrusaCalibrationNotesBraino

2015 January

The current task is to print Emmet's Gear Bearing.

http://www.thingiverse.com/thing:53451

With the "Perimeter width Test object" calibration block http://www.thingiverse.com/thing:264782 printed ok and seemed fine, emmets gear bearing is fused. The filament diameter and E-steps correction (Skeinforge) and extrusion multiplier (Slic3r) were tweaked until the Perimeter width Test object printed with the BOX width slightly LESS than 10mm and the SEAT opening was slightly greater than that. The 10mm box was 9.6 mm and the 10mm seat was 9.8 mm. However, there were gaps in the top solid layers. Ptining Emmet's gear bearing resulted in fused gears. So, back to the fist principles.

Print Calibration Process

I will use Triffid Hunter's Calibration guide. http://reprap.org/wiki/Triffid_Hunter%27s_Calibration_Guide

REquirements

• A tool to precisely measure 100mm. A vernier caliper is ideal. -- Harbor freight digital caliper $4
• A tool to precisely measure something 0.5mm wide. A micrometer is ideal, but a vernier caliper will do. -- Harbor freight digital caliper $4
• Know your stepper motors' full steps per revolution value. steps = 360 / angle, so 1.8° = 200 steps, 0.9° = 400 steps, etc.

1200 pololus are 1.8 d = 200

• Know your stepper drivers' microsteps setting. Most Pololus are set to 16x. GEN3 driver 2.3 is fixed to 2 (half step). Some boards have 32x. -- Pololus are 16x

• Know the number of teeth on your pulleys. Standard printed pulleys have 8 teeth. Most machined pulleys have 10 or 12 teeth since 8 tooth is technically too small for T5 belt

-- X- axis - 11 teeth -- Y axis - - 11 teeth

• Know your belt pitch! XL and T5 belts /look/ the same, but the difference is important!

-- T5 belt

* Know the number of teeth on your extruder gears, or at least the gear ratio.
* Remove all sources of backlash. Your parts won't be usable as calibration pieces if you have lash!
* Open the Online RepRap Calculator to find XY and E steps, layer heights, and acceleration.