Thread: Discussion Hobby City's EPO 3d-Hawk
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Old Sep 08, 2010, 02:06 AM
retiredbri is offline
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United Kingdom, England, Saffron Walden
Joined May 2008
124 Posts
Quote:
Originally Posted by Micro Fly View Post
Retiredbri...Thanks so much for sharing your knowledge
Hi Microfly

Got the 8x4.3SF and 8x6SF and compared them with the stock 8x4E. I haven't had a chance to fly with them yet - either wet or windy.

Here are the results (sorry about the table- can't get the headings and values to align)

All tests with 2S 800maH batteries
Weight of model with 800maH batteries = 245grams
Throttle position 3 = midway on the Spektrum di6E
Thrust in grams (28grms = 1oz)

Prop: 8 x 4E
Throttle amps volts watts rpm thrust
1 1.20 8.25 10 3250 37
2 3.20 8.10 26 6000 155
3 6.50 8.00 52 8000 260
4 9.60 7.30 70 9200 335
5 11.50 7.22 83 9600 395
After 80 secs, MOTOR 38deg C, ESC 29deg C

Prop: 8 x 4.3 SF
Throttle amps volts watts rpm thrust
1 1.20 8.25 10 3000 55
2 3.20 8.00 26 5500 165
3 7.00 7.50 53 7400 280
4 9.50 7.20 68 8000 375
5 11.50 7.00 81 8500 430
After 2 minutes, MOTOR 55deg C, ESC 42deg C
Prop: 8 x 6 SF
Throttle amps volts watts rpm thrust
1 1.20 8.25 10 1250 37
2 4.00 8.00 32 4800 272
3 7.80 7.50 59 6200 332
4 13.00 7.20 94 7300 402
5 14.50 7.00 102 7500 402
After 2.5mins, MOTOR 79deg C, ESC 65deg C

NOTE: With the 8x6SF, there is very little difference in prop speed between postion 4 and 5(max) except more current. I think the motor was taking more current and producing heat but only the same thrust.

The 8x4.3SF seems to give the same thrust as the 8x4E but I don't know if the slightly slower prop speed means significanly slower flying speed.

The 8x6SF would be good but I would need to severly limit the throttle end stop to position 3.5 on the Tx. Don't know how to do this with this ESC.

When it gets good enough to fly, I'll let you know how it goes.


retiredbri
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