SMKre
not an easy answer google
quote:
Gear train efficiency refers to the efficiency of gears in a power transmission system.2 Efficiency losses occur in every stage of a power transmission, and a power train is 100% efficient if there are no transmission losses.3 The efficiencies of various gear types are related to tooth friction losses only for single tooth meshes. For drive trains, the efficiencies or each mesh in the line is multiplied together, and two gears pairs of 90% efficiency result in a gear train efficiency of 81%. Spur gearing is a parallel shaft arrangement, and its efficiency varies from 94% to 98% with lower gears ratios.2 Reducer efficiency ranges from 49 to 98%, depending on the type of reducer and number of reduction stages it contains.0 Spiral bevel gears have better efficiency due to less noise and vibrations compare
enerally gear trains with lower ratios are more efficient due to reduced amount of sliding action between the gear teeth in mesh, so the compound gear train would probably be a better solution. That also depends on the quality of the gears, center distances, bearings, lubrication and thermal considerations, but short answer is two stage would probably be more efficient. If all of the components are of "good" quality, you could expect 95% or better efficiency. AGMA standard 917 goes into a lot more detail if you want to do analytics. Edit- Caveat: typically gears with fewer than 24 teeth have modified geometry to avoid undercutting the involute profile, so this could affect sliding action as well. If you change to a finer diametral pitch or module you could avoid that.
look up AGMA 917 or the super seceded spec