Hi Stuart,
I'd bolt the 2 blades on so they don't move freely ,like a mower blade use a wave washer and see how that goes.
A wave washer between the flat washer will hold some tension on the blade.
https://www.outdoorking.com.au/edge...gs-edger-blade-mounting-bolt-set-bbn6806Hi Byomarimba,
To lock the hub to the crank you would need grub screws to lock the hub to the shaft, if it's never had that it needs a bolt
in the end of the crank to hold the hub on, in your case you will need to weld a round thick washer to the end of the hub
and then tighten the bolt in the end of the crank.
If the crank has a step so the hub only goes on flush you would not need to weld the washer to the hub,
Also the last image these two parts should be locked together ,it could be welded on the other side but can't see in the image.
Cheers
Max.