Thanks for the replies - much appreciated. Agreed you need a bit more info.

Ok...the weapon is a 25kg mass of steel with 4 blades and a single cutting edge mounted either side with large bearings. Very free running and well balanced.

It is driven by two toothed belts and pulleys. The target motor rpm is about 6000 rpm to limit the tip speed on the weapon. ~3000 rpm on the weapon. The motors are turnigy sk3 6374 192kv, I am running 12S lipo system which runs at around 50V.

The VESC's are set to run at 50A max and erpm of 42000 in current mode. And the VESC settings are matched to the motors etc. The VESC's have uprated caps so should be ok at 12S.

The weapon does spin up very smoothly but slowly...

Hope thats enough !

Best wishes