Ned Simmons wrote:

The pictured 1/4" collar
is at the small end of the available range of sizes, so the
slot is wide relative to the clamping diameter which makes
the slot look wide enough to be a keyway, but I assure you
it's not.

Yes, you are right. I looked back at the puzzle photo.
I remembered the slot to be wider than it actually is.

Thanks,
Nick
--
Motor Modelle // Engine Models
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