Brilliantly Simple Detent

I’ve been obsessed with detent couplers over the past few months. All kinds of them, any kind really.

The motivation originally came out of my jewellery/rope making obsession where I’m always looking for great clasp. A machined coupler has such a beautiful look and feel to it.

They often involve ball bearings and springs:

The important aspect is to look at the indented metal around the ball bearing. That’s because the couple (pin in this case) is drilled with a bit that is only .01mm to .1mm larger than the ball bearing. You insert a spring and then the bearing. Where upon (and this is the trick) you hammer the pin and bearing with a punch just slightly bigger that the opening. This collapses the outer edge by a fraction of a mm and trapping the bearing inside the hole.
Simple, once you figure it out. It took me 3 months to figure that out. So now you can go forth and punch metal with impunity.

I recently came across another kind, even simple one for an indexing device. LINK

Fig 3.3.2: The Detent Parts

Fig 3.3.3: The Detent Engaged

Fig 3.3.4: The Detent Disengaged


It still uses a spring but instead it relies on a rotating piece of knurled brass that slots into a shaft.

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