The S4 was taxied into a plastic sheep netting stake, the propeller blade leading edge on one side only suffered a single severe dent impact which also radially cracked the trailing edge twice for several inches along its outer length.
A new propeller was not available in the U.K so a DIY repair scheme was researched. One advantage of wood is relative ease of making a satisfactory & safe repair at home.
The trailing edge cracks inner ends were stop drilled right through. A sharp penknife was used to make a clean Vee cut on both front & rear faces side to undamaged wood.
All surfaces were check inspected in strong light with an eye glass.
Then they were all filled completely in one go with a mix (for strength) of classic i.e. slow Araldite and domestic baking powder & sticky taped over to hold the correct profile without excess & to nicely flatten the surface.
A left over sample was placed on scrap wood for later testing that it had gone off & adhered correctly.
It was left to set overnight and now carefully reshaped by knife, file and wet & dry papering. Static rebalancing followed the recommended Rans manual method, a 1" round bar through the prop hub is rested on the open jaws of a bench vise. Checked both ways it is surprisingly sensitive. Better could be to roll the bar on a pair of horizontal sharp edges.
Lastly it was protective painted over both ends equally to match and cover the repair. Final rebalancing only needed an easily detected lick of paint.
It's been repaired & in service 1 & 1/2 a year now without any signs of distress.
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