I received the new 64 mm 3S/4S EDF and did some static testing. All my static testing is full-throttle for 30 seconds. Kind of disappointed in these results. I tried two different EDF/ESC/Battery systems with pretty much the same results:
System 1 (Higer mass):
1300 mAh Lumenier 4 cell 150c battery
60 Amp Avian ESC
64 EDF 3S/4S
Average 1.12 Kg
Minimum 1.08 Kg
Maximum 1.21 Kg
System mass 0.371 Kg
Thrust/mass is 3.02
End voltage: 15.74 V
System 2 (Lower mass):
1150 mAh Lumenier 4 cell 150c Battery
50 Amp Hobbywing ESC
64 EDF 3S/4S
Average 1.07 Kg
Minimum 1.03 Kg
Maximum 1.15 Kg
System mass 0.315 Kg
Thrust/mass is 3.40
End Voltage: 15.65 V
System 1 right and System 2 on the left.
So, the second system is a bit better. I decided to use thrust/mass (no units) to compare the systems. This is important because all the other mass in the airframe, etc. stays the same. I also check how the battery recovers. You would expect that the smaller capacity battery would be less, but it was still OK.
But, I came to the conclusion that
neither of these systems will be adequate. So, I decided to go back through the others I tested and perhaps even use the heavier 70 mm EDF again.
For example, look at the data for one of the 70 mm EDF tests I conducted:
System mass was 0.507 Kg and the average thrust was 1.70 Kg. So the thrust to mass was 3.35.
On the other hand, I got an excellent result from the 64 mm 3S EDF using a 4 cell battery. The rating on the motor is 3900 KV (again, not kilovolts) so with the higher voltage, this motor cranks. So, I did another static test this morning:
System 3:
1300 mAh Lumenier
4 cell 150c Battery
50 Amp Hobbywing ESC
64 mm EDF
3S
Average 1.38 Kg
Minimum 1.34 Kg
Maximum 1.47 Kg
System mass 0.351 Kg
Thrust/mass is 4.19
End Voltage: 14.81 V
It really discharged the battery to storage level, but wow, lots more thrust. The maximum is always at the start, so the 1.47 Kg thrust is going to help get the rocket going quickly off the pad. I will almost have the 2:1 thrust to mass I was trying to achieve.
So, I'm going with system 3, and I'm going to start the final assembly and test the deployment system.