If you don't have any thread gauges take an axel with a thread which you know is metric and see if they are the same by using the same method you would with a thread gauge.
Use some calipers for the diameter.
@TheBrick(Tommy) started
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If you don't have any thread gauges take an axel with a thread which you know is metric and see if they are the same by using the same method you would with a thread gauge.
Use some calipers for the diameter.