So I have a fundamental understanding of mechanical ratios and motors, but I don’t understand why certain combination are said to be preferred - such as the preference of high torque motors paired with high speed gears over high speed motors paired with high torque gears. I also don’t understand how one max/min the system to achieve the highest rps (a proxy for trigger response) and fps.
On both my AEG I am using an ASG U-18000 motor, said to be around 26ish TPA, and SHS 12:1 gears (which I realize when you count the teeth, it’s more like 12.6:1). Currently I am using M110 spring and can shoot .28 bbs at 1.74 joules with 22 rps as measured via chrono and reconfirmed via audio using audacity.
When you work the math out (I’m going to round the numbers to make the math easier):
18000 motor is 300 revolutions per second. This means the pinion spins 300 times a second
Based on the gears ratio of 12:1, The sector gear should yield 25 cycles (shots) per second
Since I get 22 rps via chrono — I’m going to attribute the real life ‘yield’ being lower in part to the motor ramp up speed, me only having bushings, rounding errors, and etc. Regardless of all this…the math seems right.
Now having said all this, why do people not use High speed motors and High torque gears?
Let’s us examine an ASG -45000 motor and SHS 32:1 gears with all other things being equal
45000 motor would be 750 revolution per second. This means the pinion would spin 750 times a second
Based on a gears ration of 32:1, The sector gear should yield 23.5 cycles (shots) per second
And before someone saids a 45000, 13TPA, motor can't pull a M110 spring...why not if you're using 32:1 ratio gears?
This isn’t too far from 25… and one could easily use a different gear set, say 18:1 gears? And that should yield 41.5 cycles per second.
So what am I missing here exactly? Is high torque motor and speed gears just a convention everyone assumes is correct, or is there something else I’m not understanding? Ultimately we are just converting the electrical energy from the LIPO to mechanical energy in the piston, I don’t see how one combination of motor/gear is superior to another combination.
Input appreciated!
On both my AEG I am using an ASG U-18000 motor, said to be around 26ish TPA, and SHS 12:1 gears (which I realize when you count the teeth, it’s more like 12.6:1). Currently I am using M110 spring and can shoot .28 bbs at 1.74 joules with 22 rps as measured via chrono and reconfirmed via audio using audacity.
When you work the math out (I’m going to round the numbers to make the math easier):
18000 motor is 300 revolutions per second. This means the pinion spins 300 times a second
Based on the gears ratio of 12:1, The sector gear should yield 25 cycles (shots) per second
Since I get 22 rps via chrono — I’m going to attribute the real life ‘yield’ being lower in part to the motor ramp up speed, me only having bushings, rounding errors, and etc. Regardless of all this…the math seems right.
Now having said all this, why do people not use High speed motors and High torque gears?
Let’s us examine an ASG -45000 motor and SHS 32:1 gears with all other things being equal
45000 motor would be 750 revolution per second. This means the pinion would spin 750 times a second
Based on a gears ration of 32:1, The sector gear should yield 23.5 cycles (shots) per second
And before someone saids a 45000, 13TPA, motor can't pull a M110 spring...why not if you're using 32:1 ratio gears?
This isn’t too far from 25… and one could easily use a different gear set, say 18:1 gears? And that should yield 41.5 cycles per second.
So what am I missing here exactly? Is high torque motor and speed gears just a convention everyone assumes is correct, or is there something else I’m not understanding? Ultimately we are just converting the electrical energy from the LIPO to mechanical energy in the piston, I don’t see how one combination of motor/gear is superior to another combination.
Input appreciated!