Can any body help with what size Three bladed prop would be OK on a OS46 AX . Yours Paul T

A Master Airscrew 10x7 should be fine but the Master Airscrew 11x6 ought to work too. They are a little narrower in blade width, thus the 11x6 should work. A wider 3 blade prop maybe would require you to stick to a 10x7 size then.

Graupner has a 10x8.3 too.

Thanks all for the information. I have also found a supplier that stocks more than one brand so all is good. Yours Paul T