Good info. I finished soldering them tonight and have them on the charger as I type. I'll run some more tests in the morning once the neighbors are awake.

Originally Posted by GryphonRCU

moparmyway,

What's the white box in the upper left of your Eagle Tree screen shots?
Is that the results from the moment in time where mouse is located?

It is the actual value for the curser.

While in the 2D chart, top left of the screen you will see "curser" on the rightmost box. Click it and then click "set curser" ................. the box appears with curser data !

I put my almost-new (two flights) FJU onto its nose this morning after a bad launch. Its OK but has a bent nose. I was using:
e-Flight 6 series 2700kv
3s2250
6X4
draws 40A max
Im getting 125mph in a dive.
I reckon a 6X5.5 is a better option or possibly 6.5X6.5 if the motor can take it.
This is a tempory motor untill my SK3 arrives.Im looking forward to a setup with more torque. 7" prop should be much better.

If you have the sticker pulled off and put a heatsink around the motor, you could run 4 cells with the 6x4 Sport for more speed untill your sk3 arrives

I didn't think of that - thanks !
I'll try that.

Originally Posted by GryphonRCU

nofreee,

Lets see how the data changes with your bigger pack.....AND it will change.

See my attachment. Actual data from one of my tests in order to show some other folks the effects of running various size packs.


on my graph:
See the effect of battery size change on weakest prop (RPM and Watts).....then look at the changes on the highest load prop.



Gryphon

Got some more numbers this morning. As expected, the power went up by a good chunk.

With 4s 2650 35-70c..

5x5 - 72a 1070w
5.25x4.75 - 80a 1170w
5.5x4.5 - 83a 1225
5.5x5.5 - Did not test

Fairly large gains as you predicted. I'm shooting for 135mph, do you think it is possible with this setup?

nofreee,

If it was mine, I would just start with APC E 5.5X4.5 and a good size heat sink and some throttle control.

Check temps, Measure the speed and take it from there.

Hopefully others who know that specific motor will chime in.

Note: the motor is not maxed out yet......everything should run real nice.
***Don't count out 5.5X5.5 yet.

APC 5.5X4.5 will be more fun than 5.2X5.2 Graupner but consider picking that up sometime and see how you like the speed etc.


Per cell Voltage under load: (Watts / AMPs) / 4

Gryphon

Originally Posted by GryphonRCU

nofreee,

If it was mine, I would just start with APC E 5.5X4.5 and a good size heat sink and some throttle control.

Check temps, Measure the speed and take it from there.

Hopefully others who know that specific motor will chime in.

Note: the motor is not maxed out yet......everything should run real nice.
***Don't count out 5.5X5.5 yet.

APC 5.5X4.5 will be more fun than 5.2X5.2 Graupner but consider picking that up sometime and see how you like the speed etc.


Per cell Voltage under load: (Watts / AMPs) / 4

Gryphon

Thanks. I'm about the hit the field in a few minutes and will see how she does.

I'm going to start with the 5.25x4.75 and check the temps before moving up as I don't have a heatsink on it right now.

Just got back from the field..

Once it was trimmed out it flew great. One of the guys had me on rcspeedo doing 130, 133 and 142 (out of a small dive). I still need to get the thrust line dialed in as it was nosing up under heavy throttle. I think that with a smooth approach that I can hit 135 level.

The motor seemed to be pretty cool after each run. I put my infrared thermometer on it after each run and it was only showing high 80's on the can. Ambient temps were about 72 at the field. Something tells me the motor should be hotter than that, but as you know it is a very small gap between the motor mount and mounting "plate" to get a reading.

What glue works best to assemble the FJU?

I used Gorilla glue on mine, the fast drying white kind. It's lasted so far on my 140mph setup

I tried a 6X5.5 this morning and it was much better. There was also a strong wind which helped the launch.
Peak amps were 58A. Max temp of motor and esc was 110F and 130F.
I was getting 135mph down wind.
My concern with using 4S is my Hyperion 50A esc is only rated to 3S.
Do you think it will handle 4S ?

Originally Posted by moparmyway

If you have the sticker pulled off and put a heatsink around the motor, you could run 4 cells with the 6x4 Sport for more speed untill your sk3 arrives

Originally Posted by War Machine

My concern with using 4S is my Hyperion 50A esc is only rated to 3S.
Do you think it will handle 4S ?

No, I dont think you should try 4 cells with that ESC ............... how are you coming up with your numbers ?

Hitech telemetry.

Which would be better foam safe ca or epoxy... Or should I go and get gorilla glue (white) I'm going to start my build tonight


Thanks