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Posted by vienquach | Jul 09, 2021 @ 08:58 AM | 7,261 Views
Relax to look at after a long day at works.
Posted by vienquach | Dec 27, 2020 @ 11:20 PM | 12,950 Views
Built 2010, maiden flights 2020.
Hacker A50 12s V3 480kv, ICE 100, Xoar 18x8, Turnigy Nano 6s 3000 30C.
Castle BEC Pro 6.5V, Align DS610 servos.
84A, 1716W, weight = 8.5 LBS, 202 W/lb.
Light weight, good throttle response, hover @ little more than half throttle, 5 min flight, ambient 45F.
Posted by vienquach | Oct 16, 2020 @ 03:06 PM | 8,474 Views
Hacker motors, 600w to 6000w .
They seem to have best built quality from brands that I know of.
Too many motors, too little time to fly.
Posted by vienquach | Aug 09, 2020 @ 03:46 PM | 12,138 Views
Life changed but this 20 year old hobby didnít.
Posted by vienquach | Oct 27, 2011 @ 10:36 AM | 22,915 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 | 22,646 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 | 23,084 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 | 27,956 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 | 22,422 Views
Weight readings are in the photos.
Will add more if I have a chance to take photos of other motors.

Posted by vienquach | Sep 20, 2011 @ 10:29 AM | 24,411 Views
At half the cost, the Infinite S4020-540 sounds like a great alternative for Hacker A40-L, Torque 4016, or Scoprion S4020-540. These motors are all in the $100.00 - $150.00 price range. That was why I wanted to give the Infinite several test runs to see how a $40.00 performs comparing to the others.

The built quality is great. The spec (weight, dimensions, kv) is quite close to the Scorpion S4020-540's even though it's only rated for 800 W continuous whereas the Scorpion is 1500 W. At the end of the test, however, I could tell that the rating on the Infinite motor is VERY conservative since I was able to run 1100 - 1200w continuous (on 5s-3300) without heating problem. On a burst with 6s and Xoar 15x8, the Infinite pulled 1600w for at least 10s, and the motor temp was just around 100 F from (50-55 F ambient). Anyway, I'd love to have the Scorpion S4020-540 to compare to its similar cousin Infinite S4020-540, but unfortunately I dont have the extra $150.00 to spend on another motor just to try.

The thrust vs. watt data of the two motors (Inf S4020 and A40-10L) is attached below (photos).

Infinite S4020-540 kv Static Test (0 min 44 sec)

Posted by vienquach | Sep 10, 2011 @ 04:16 PM | 22,702 Views
1) September 9th, 2011

Did several test flights today with different power systems. 70F ambient, 15-25 mph cross wind.

a) A40-10s (750kv, 205g), Gens ACE 4s-3800, Xoar 15x8, 68A, 15.4V, 1047W. 8 min flight, motor & ESC warm --> plenty of power and speed, great setup.

b) A40-10L (500kv, 276g), Gens ACE 5s-3300, Xoar 15x8, 46A, 19.5V, 897W. 10 min flight, motor and ESC COOL --> more than enough power, great vertical, enough speed. I like this.

c) A40-10L, Gens ACE 5s-3300, Xoar 16x8, 55A, 19.2V, 1056W. 10 min flight, motor slightly warm, ESC cool --> hovered like a heli, lacking speed and difficult to roll @ end of flight. I prefer the 15x8 prop unless you want to hover all day long.

d) A40-10L, BL 6s-2650 30C, Xoar 15x8, 58A, 21.8V, 1264W. 10 min flight, motor slightly warm, ESC cool, great speed, but "too much power" made me nervous. I will try to like this.

That's it. My generator ran out of gas (filled last week).

2) September 10th, 2011

3 props with Hacker A40-10s, Gens ACE 4s-3800 25C. 74F ambient, 5mph wind.

a) APC 14x7, 7 min flight. Motor slightly warm, enough speed, but lacking punch out of hovers. Put back 1.9 Ah --> 14.8V x 1.9Ah = 28.1 Wh used.

b) APC 15x8, 7 min flight. Motor warm (hold > 10s), better speed, more thrust in hover, slower throttle response. Put back 2.15 Ah --> 14.8V x 2.15A = 31.8 Wh used

c) Xoar 15x8, 13 min flight. Motor warm (hold >...Continue Reading
Posted by vienquach | Sep 04, 2011 @ 01:38 AM | 23,153 Views
Used to be a stand for my DLE 55.
It seems to be useful whenever I want to put up a motor-prop combo to get some power reading (instead of having to put on an airframe).
Last photo is my old little test stand with a fish-scale to measure thrust.

--> Current is measured from an Amp meter (clamp type).
--> Voltages (with & without load) are read from voltage telemetry on the Aurora 9 transmitter. Could use the difference to calculate internal resistance (IR) of the lipo packs.

Posted by vienquach | Aug 26, 2011 @ 01:20 PM | 25,370 Views
Last year bd present from her.

Infinite A3007-1100 kv, APC 11x5.5
Hobbywing Pentium 30A
Blue Lipo 3s-2200 20C
EXI s1123 servos
AUW 27 oz

Posted by vienquach | May 25, 2011 @ 09:22 PM | 23,290 Views
1) My first heli build, EXI 450CF.

Motor: Typhoon 2215H, 11T pinion
ESC: Hobbywing 40A pentium
Servos: EXI s1123 cyclic, HS-225hb tail
Rx: Optima 6

2) TRex 600 EFL
Stock setup
Posted by vienquach | May 25, 2011 @ 09:15 PM | 23,261 Views
Just to make a good combo with my 72" SC (along with the 70" & 51" Slick combo)

1) Previous setup (A40-14s would be better)
Motor: Rimfire .55 (268g, 480kv)
ESC: Castle Ice 50
Lipo: 6s-2200 30C, 2650 30C, 3000 20C, 3800 25C, 4000 30C
Power: APC 15x8, 50A, 1150W, 4.7 lbs ~ 240 W/lb

2) Current setup:
Motor: A30-12XL
ESC: Castle ICE 75
Lipo: Blue Lipo 4s-4000 30C, Gens ACE 4s-3800 25C

Servos: HS-225 MGs on elevator & rudder, 225-HBs on ailerons
Rx: Optima 7 with voltage telemetry
Posted by vienquach | Dec 20, 2010 @ 11:31 PM | 24,713 Views
Here is my little Slick 51". Also blue to be a good combo with the 70"

1. Setup:
a. Motor: Infinite A3025 (770kv, 181g) w/ Xoar 14x7
b. ESC: Hobbywing Pentium 60A
c. Servo: Hobbico CS-110 digital
d. Radio: Aurora 9, Optima 6 w/ SPC used
e. Battery: 4s-2200-25c Nano

AUW ~ 58 oz, 830 w --> 229 w/lb

It's been my go-to plane lately ... especially when it's too cold to fly the 70".
Well, dont have many photos for this one.
Posted by vienquach | Dec 20, 2010 @ 11:07 PM | 24,918 Views
1. Prop used: APC 15x6 and 15x8.
2. Battery: Blue Lipo 4s-4000-30C for Castle and Hacker motors
Gens ACE 6s-3800-25C for Rimfire .55 motor


a. Built quality: Castle and Hacker are much better built than the Rimfire. Running at higher power than the Rimfire (~1200 w vs. 1000w), the Castle was much cooler (120F vs. 146F, probably due to its larger casing).

b. Motor spec
- A30-12XL : 182 g, 700kv, 37 x 49 mm
- Castle 34-24-750: 251 g, 43 x 54 mm
- Rimfire .55: 290 g, 480 kv, 42 x 60 mm

Posted by vienquach | Dec 20, 2010 @ 06:15 PM | 24,180 Views
1. Setup
Motor: A50-16s with Xoar 19x10
ESC: Castle 85 HV
Servos: 7955 TG (rudder), s9156 (elevator), 5625 MG (ailerons) using CC BEC Pro
Radio: Aurora 9, Optima 7 Rx w/ SPC
Blue Lipo 6s-4000-30c (4s + 2s in series)
AUW: 9.2 lbs ... feels really light in the air

2. Watt reading
Blue Lipo 6s-4000-30c, Xoar 19x10: 92.5A x 23.7V = 2192w
Blue Lipo 6s-4000-30c, Xoar 19x8: 80A x 21.9V = 1752w
Motor temp: stator 130 F, rotor 109 F

3. New Setup:
Motor: A50-14L with Xoar 19x10
Servos: HS-5625MGs (ele + rudder), TS-150 MGs (ailerons)
Lipos: Gens ACE 8s-3300 25C
Posted by vienquach | Dec 20, 2010 @ 06:03 PM | 24,122 Views
1. Got it in Oct 2010. My first 3DHS plane and really enjoy it.

a. Motor: Infinite A5020-250 kv with APC 20 x 10
b. ESC: Castle ICE 80 HV
c. Servos: 7955 TG (rudder), 5665 MH (ailerons, elevator) using 2s-800 Lipo
d. Radio: Aurora 9, Optima 7 Rx, SPC used
e. Blue Lipo 8s-4000-30c (4s packs in series)

AUW: 9.8 lbs

2. Watt reading
Blue Lipo 8s-4000-30c, APC 20x10: 58 A, 31.2V = 1810 w (tired pack)...Continue Reading