Perhaps a single machined key in the spindle lined up with a brazed male key on the arms would work if you do find slippage
Edit: the pinch bolt looks pretty beefy, I reckon it'll be fine
@PhilDAS started
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Perhaps a single machined key in the spindle lined up with a brazed male key on the arms would work if you do find slippage
Edit: the pinch bolt looks pretty beefy, I reckon it'll be fine