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Each component in the drivetrain category has its own unique tests.

V-wheel

Test Description Target Tolerance
Outer diameter Measure the outer diameter of the v-wheel with digital calipers. 23.89mm +/- 0.1mm
Inner diameter Measure the inner diameter of the v-wheel (where the bearings will sit) with digital calipers. 15.974 +/- 0.05mm
Width Measure the width of the v-wheel with digital calipers. 10.23mm +/- 0.1mm
Smoothness Inspect the wheel to ensure there are no eroneous grooves, cuts, or knicks No blemishes N/A

GT2 Timing Belt

Test Description Target Tolerance
Length Measure the length of the belt using a measuring tape. See BOM spec. +/- 1cm
Width Measure the width of the belt using digital calipers. 5mm +/- 0.25mm
Pitch Measure the distance between one tooth and another one 50 teeth away using digital calipers, then divide by 50. 2mm +/- 0.02mm (1%)
Thickness Measure the thickness of the belt using digital calipers. 0.75mm +/- 0.05mm
Stretchiness Tie a belt to a fixture 1.5m or more off the ground. Mark the belt just below the knot and then add a second mark exactly 1000mm below the first. Hang a 10kg weight from the belt (below the 1000mm mark) and measure the distance between the two marks. 1000m + 10mm (1%)
Strength Use a tensile testing machine to measure the equivalent hung weight at which the belt will break. 100kg - 20kg
Color Inspect the belt for any discoloration or markings Black, no markings. N/A

GT2 Pulley

Test Description Target Tolerance
Number of teeth Count the number of teeth on the pulley. 20 +/- 0
Pitch Mate the pulley with a belt and inspect tooth engagement The pulley should fully engage the belt’s teeth at all points of contact. N/A
Tooth width Measure the width of the teeth using digital calipers. 7mm +/- 0.5mm
Overall length Measure the overall length using digital calipers. 14mm +/- 0.5mm
Outer Diameter Measure using digital calipers. 15mm +/- 0.5mm
Hole diameter Measure the diameter of the motor shaft hole using digital calipers. 5mm + 0.05mm
Number of setscrews Count the number of setscrews. 2 N/A
Setscrew drive size Use a hex driver to validate the drive size of the setscrews. 2mm N/A
Material Ensure the material is aluminum and stainless steel and will not rust by holding a magnet to the part. Aluminum and stainless steel (no magnetic attraction) Weak attraction to stainless steel is permissible.

Belt Sleeve

Test Description Target Tolerance
Inner width Measure using digital calipers. 7.5mm +/- 0.1mm
Inner height Measure using digital calipers. 2.15mm +/- 0.05mm
Outer width Measure using digital calipers. 10mm +/- 0.2mm
Outer height Measure using digital calipers. 5mm +/- 0.2mm
Length Measure using digital calipers. 10mm +/- 0.5mm
Material Ensure the material is aluminum and will not rust by holding a magnet to the part. Aluminum (no magnetic attraction) N/A
Sandblasting Inspect for thorough sandblasting coverage. 100% -1%
Anodization Inspect for thorough annodization coverage. 100% -1%
Deburred Inspect for burrs. No burrs 0

5mm to 8mm Shaft Coupling

Test Description Target Tolerance
Inner diameters Measure using digital calipers. 5mm and 8mm +/- 0.05mm
Outer diameter Measure using digital calipers. 18mm +/- 0.5mm
Length Measure using digital calipers. 25mm +/- 0.5mm
Setscrew drive size Use a hex driver to validate the drive size of the setscrews. 2mm N/A
Material Ensure the material is aluminum or stainless steel and will not rust by holding a magnet to the part. Aluminum and stainless steel (no magnetic attraction) Weak attraction to stainless steel is permissible.
Fits motor shaft Connect the coupling to a motor shaft. The coupling should be easy to connect and resist pulling off by hand once tightened. N/A
Fits leadscrew Connect the coupling to a leadscrew. The coupling should be easy to connect and resist pulling off by hand once tightened. N/A

Leadscrew

Test Description Target Tolerance
Length Measure the length using a measuring tape. 800mm +/- 3mm
Threads Thread the leadscrew into the delrin leadscrew block. The leadscrew should thread as expected without significant resistance. N/A
Straightness Place the leadscrew on a reference table with a flatness tolerance of 0.5mm per 1m or better. 0mm deviation + 2mm
Deburred Inspect for burrs, especially on the cut ends. No burrs 0
Material Ensure the material is stainless steel and will not rust by holding a magnet to the part. Stainless steel (no magnetic attraction) Weak attraction to stainless steel is permissible.

Leadscrew Block

Test Description Target Tolerance
Size Measure the outer dimensions of the block with digital calipers. 34mm x 20mm x 12mm +/- 0.5mm
Threads Thread a leadscrew into the block. The leadscrew should thread as expected without significant resistance. N/A
Hole diameter Measure the hole diameter using digital calipers 5.25mm +/- 0.1mm
Hole spacing Attach the block to a cross-slide plate according to the FarmBot system design. The block should attach without screw/hole interference. N/A