3D Printer Quality Control

User Issues

Feedback on issues - picture/vid shared folder - [1]

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Overall List of Quality Control Procedures

D3D_Pro_Production_Engineering#Quality_Control

Quality Control Requirements - 12 Kits at a Time

To produce and test 12 kits at a time, it is useful to set up rapid production and testing procedures for parts.

From the 3D Printer Packing List:

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Requirements for Perfect Prints

To guarantee perfect prints, the following conditions must be met:

1. Extruder steps per mm are correct. See Triffid Hunter's Calibration Guide
2. Axes must be able to move freely. See 3D Printer Manual - final assembly for procedure to mount axes
3. Axis range of motion must be over the entire bed, as determined by both geometry and friction. Do D3D Burn-In for 20 minutes to verify all motion.
4. There must be no play in the mechanical systems
5. There are no inertial effects such as wobbling of printer, extruder, or bed - when the extruder is moving at high speed.
6. There are no feed issues related to melt rate of the plastic. To address this, the Volcano nozzle should be used to allow for faster extrusion with larger nozzles.

Testing for Correct Motion

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Baseline Speed

X axis - about 0.25kg overall friction on x:

300 mm/sec is ok - back and forth on x:

• Gcode used for x test - File:Backforth x.ini (note: .ini is just a text file - replace .ini with .gcode to use it in Marlin)
• Gcode used for y test - File:Backforth y.ini
• Gcode used for xy test - File:Backforth xy.ini

Axis Friction

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Friction Data

1. Measure axis tightness using a force meter. Use a Digital Scale to record the force required to move an axis.

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Spiral Data Collection

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Burn-In

See document:

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Z Offset

• Use Cell Phone Microscope and reference object for height, such as 0.4 mm needle
• Optimize Z offset from extruder. Measure variation over multiple prints and graph the results for a 2 cm square.
• Measure variation over perimeter and graph this variation.

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Bed Adhesion

• Optimize heated bed temperature. Measure force required to pull a columnar object off the bed using a digital scale

Extrusion

1. E steps/mm must be done only once, and must be captured in Marlin or in Start G-Code
2. Optimize temperature for a given filament. See Triffid Hunter's Calibration Guide

Electronics

• See [2]

Make Printer Ratings

Make Zine tests for:

1. Vertical Surface Finish
2. Horizontal surface finish
3. Dimensional accuracy
4. Overhangs - see how to go beyond 45 degrees here - [3]
5. Bridging - ability to print on air - [4]
6. Negative space
7. Retraction performance
8. Support material
9. Squareness
10. Full bed accuracy
11. Z wobble

Printer Evaluation

Evaluation criteria:

Improvements

• Increase volume with different mounting
• Remount the Titan Aero underslung
• Omnidirectional air duct?
• Optimize bed temperature - if print has elephant feet - reduce temperature - [5]
• Slow down if you see ringing - [6]. But then again, try to get more mechanical stability in the 3D printer.

Links

• For OSE's 3D printer stable release, this can be done once: Triffid Hunter's Calibration Guide