Thanks for that info torque wrench.

I am going to have to buy a graupner prop I see

I have bought Master Airscrew and now an APC and never had any info with them. Some were bought at the local hobby shop and others were bought online nobody gave me any info [>:]

Being primarily a slope soarer I thought a prop was just a prop ! Playing around with some engines I now realise I may have to experiment with different types.

The learning continues......