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Archive for October, 2011
Posted by vienquach | Oct 27, 2011 @ 10:36 AM | 15,673 Views
Rimfire 300, 28-22-1380 kv.
Electrifly 10A ESC.
Dynam 6g servos, $3.50 / two.
2s-500mah for indoor, 2s-800mah for outdoor.
Prop: 8x4 Sloflyer
AUW: 8.4oz without lipo.

Small, cheap, but flies well (no aileron) and very fun.

Flylite Night Flying, 33F, 15 mph Wind (0 min 43 sec)

Posted by vienquach | Oct 20, 2011 @ 11:09 AM | 15,471 Views
*) Running recommended setup with:
a) Hacker A40-12s V2 (610kv), 236g motor only, 244g with A40 X mount, 252g with A50 X mount (I use this).
b) Castle ICE 100, (August 2011), Cut off 3.0V, Norm 150A, Soft ; BEC 6.0V ; Motor Norm 5, Forward, 12 kHz.
c) HS 225 MGs
d) Optima 7 with SPC voltage telemetry
e) Gens ACE 5s-3300 25C (470g vs. listed 447g)

*) Weight & Power:
--> 5.06 lbs without spinner and wheel pants
--> Xoar 15x8: 1233 W @ 65 A, 19.0 V, 244 W/lb (fresh pack); 1057 W @ 59 A, 17.9 V, 209 W/lb (tired pack).
--> Xoar 14x7: 960 W @ 50 A, 19.2 V, 190 W/lb (fresh pack); 825 W @ 45 A, 18.3 V, 163 W/lb (tired pack).

In this season, the Hacker A40-12s comes down cool after an 8 min flight with Xoar 15x8, put back 2000 mah in to the 5s-3300 mah pack.
In the summer, I think it will get hot with this power level, so throttle management is necessary. Otherwise, the Motrolfly 3620-560 kv (approximate) might be a better option. The Motrolfly 4315 is a much stronger motor (305g, 1500W capable), however, with the slightly forward CG design, about 1/2 - 1 oz of lead might need to be added to the tail to balance.

Update (11/11/11)
A bad harrier landing killed the landing gear mount on my Slick 59". Never fixed something like this before. So I used the landing block from my SC 57", the only part that I couldn't sell.
Finished covering the damaged part on the Slick. Already tried my best, and now I can say that I have a &...Continue Reading
Posted by vienquach | Oct 02, 2011 @ 12:33 AM | 15,975 Views
Haven't got a chance to measure the static thrust, but I have got some watt and current readings from the latest runs. The Motrolfly 4325-295 was custom wound for Xoar 19x10 prop, and the result falls right into my favorite power and temperature range, so I did not bother to test other prop combos. Ambient was about 70 F. For comparison, I tested a new Hacker A50-14L V1 with Xoar 19x8, Xoar 19x10, and APC 18x10 props.

1) Motrolfly 4325-295 kv (510g), Gens ACE 8s-3800 25C, ICE HV 80, Xoar 19x10

---> 30.0 V x 84 A = 2520 W.
.... After the test, I ran it continuously for 15s at WOT. Motor was slightly warm, the hottest part (stator) was around 115 F.

2) Hacker A50-14L V1, Blue Lipo 8s-4000 30C, ICE HV 80,

a) Xoar 19x8, 29.7 V x 79 A = 2346 W
b) Xoar 19x10, 29.3 V x 88 A = 2578 W
c) APC 18x10, 29.0 V x 92 A = 2668 W

... The APC 18x10 was the worst, too much prop noise and didn't pull very strong, highest current draw --> lowest efficiency.
... After the test, I ran it continously for 15s at WOT with the APC 18x10. Motor was warm at about 130 F. Would be a lot cooler with the Xoar 19x10.
So I would recommend spending $5 - $10 for the Xoar. Much more efficient and stronger.

--> These two motors will work very well on the Slick 71" and SC 72" from 3DHS. 8s batteries are required, and Xoar 19x8 and 19x10 are the best prop. My favorite prop is 19x10.

Posted by vienquach | Oct 01, 2011 @ 07:12 PM | 20,326 Views
I have some test data with my new Motrolfly 4315-500kv (recorded today). Equipments used were Castle ICE 2 HV 80, Gens ACE 5s-3300 25C (470g), Gens ACE 6s-2200 25C (346g), APC 15x8, Aurora 9 w/ Optima 6 receiver.

a) On 5s, 19.6 V x 52 A = 1019 W, 149 oz static thrust on a fresh pack
.............18.4 V x 43 A = 791 W, 135 oz static thrust on a tired pack

b) On 6s, 23.0 V x 61 A = 1403 W, 180 oz static thrust on a fresh pack
.............21.3 V x 55 A = 1172 W, 165 oz static thrust on a tired pack.

After the test, I ran it on 6s for at least 20s. The rotor was slightly warm, and the stator was just warm (115F or so). I highly recommend this 4315-500kv for 3D planes (55" - 60") such as SC 57", Slick 59", EF Edge 60" on 6s. Ken told me that it should be able to handle 75A.

Photos of the motor and weight are below.

Posted by vienquach | Oct 01, 2011 @ 06:49 PM | 15,348 Views
Weight readings are in the photos.
Will add more if I have a chance to take photos of other motors.