Appendix 1: Methodical Testing

On this page:

1 Overview
2 Find the Accurate Axle Measurement
- 2.1 HYPOTHESIS
- 2.2 METHODOLOGY
- 2.3 TESTS AND RESULTS
- 2.4 CONCLUSION
3 Bonus Testing
- 3.1 HYPOTHESIS
- 3.2 METHODOLOGY
- 3.3 TESTS AND RESULTS
- 3.4 CONCLUSION

Overview

Because of the inconsistencies in how the M12 cap nut schematic on the Voro Motors website is labeled and the mismatch between what I thought was an M12-1.5 cap nut versus the M12-1.25 measurement of the axle, I needed to develop a methodical testing approach to identify the accurate size of the EMOVE Touring's rear axle.

In other words, LET’S DO SCIENCE!

Find the Accurate Axle Measurement

HYPOTHESIS

If the correct measurement of the rear axle of my EMOVE Touring scooter is M12-1.25, then neither M12-1.55 nor M12-1.75 nuts will fit the rear axle.

METHODOLOGY

Purchase nuts nuts in each of the following sizes: M12-1.25, M12-1.5, M12-1.75
Check each nut against the corresponding thread checker unit.
- Reasoning/assumption: If the labeled nut sizes match the corresponding thread checker size indicators, then:
  1. The thread checker is accurate and can be trusted.
  2. The nuts are labeled correctly.
Check the rear axle against each size M12 thread checker unit.
- Assumption: The thread checker that fits the rear axle will indicate the accurate size of the axle bolt.
Verify by testing whether each size nut fits on the rear axle.
Predicted outcome: The thread checker and nut that fit the axle will indicate the actual, accurate size of the rear axle.

TESTS AND RESULTS

Test cases and results are listed in the table below.

	Test Case	Expected Result	Actual Result	Pass/Fail

	Test Case	Expected Result	Actual Result	Pass/Fail
1	Check the nut labeled `M12-1.25` against the thread checker labeled `M12-1.25`.	The nut labeled `M12-1.25` will fit the thread checker labeled `M12-1.25`	The nut labeled `M12-1.25` did fit the thread checker labeled `M12-1.25`.	PASS
2	Check the nut labeled `M12-1.5` against the thread checker labeled `M12-1.5`.	The nut labeled `M12-1.5` will fit the thread checker labeled `M12-1.5`.	The nut labeled `M12-1.5` did fit the thread checker labeled `M12-1.5`.	PASS
3	Check the nut labeled `M12-1.75` against the thread checker labeled `M12-1.75`.	The nut labeled `M12-1.75` will fit the thread checker labeled `M12-1.75`.	The nut labeled `M12-1.75` did fit the thread checker labeled `M12-1.75`.	PASS
4	Check the thread checker labeled `M12-1.25` against the rear axle bolt.	The thread checker labeled `M12-1.25` will fit the rear axle bolt.	The thread checker labeled `M12-1.25` did fit the rear axle bolt.	PASS
5	Check the thread checker labeled `M12-1.5` against the rear axle bolt.	The thread checker labeled `M12-1.5` will not fit the rear axle bolt.	The thread checker labeled `M12-1.5` did not fit the rear axle bolt.	PASS
6	Check the thread checker labeled `M12-1.75` against the rear axle bolt.	The thread checker labeled `M12-1.75` will not fit the rear axle bolt.	The thread checker labeled `M12-1.75` did not fit fit the rear axle bolt.	PASS
7	Try to put the nut labeled `M12-1.25` on the rear axle bolt.	The nut labeled `M12-1.25` will fit the rear axle bolt.	The nut labeled `M12-1.25` did fit the rear axle bolt.	PASS
8	Try to put the nut labeled `M12-1.5` on the rear axle bolt.	The nut labeled `M12-1.5` will not fit the rear axle bolt.	The nut labeled `M12-1.5` did not fit the rear axle bolt.	PASS
9	Try to put the nut labeled `M12-1.75` on the rear axle bolt.	The nut labeled `M12-1.75` will not fit the rear axle bolt.	The nut labeled `M12-1.75` did not fit the rear axle bolt.	PASS

The M12-1.15 thread checker fits the rear axle bolt.

Bonus Testing

	Test Case	Expected Result	Actual Result	Pass/Fail

	Test Case	Expected Result	Actual Result	Pass/Fail
1	Check the `M12` nut from Voro Motors against the thread checker labeled `M12-1.75`.	The `M12` nut from Voro Motors will fit the thread checker labeled `M12-1.75`.	The `M12` nut from Voro Motors dit not fit the thread checker labeled `M12-1.75`.	FAIL
2	Check the `M12` nut from Voro Motors against the thread checker labeled `M12-1.5`.	The `M12` nut from Voro Motors will not fit the thread checker labeled `M12-1.75`.	The nut labeled `M12-1.5` did fit the thread checker labeled `M12-1.5`.	FAIL
3	Check the `M12` nut from Voro Motors against the thread checker labeled `M12-1.25`.	The `M12` nut from Voro Motors will not fit the thread checker labeled `M12-1.25`.	The `M12` nut from Voro Motors did not fit the thread checker labeled `M12-1.25`.	PASS

The M12 cap nuts from Voro Motors only fit the M12-1.5 thread checker.