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Posted by jmxp69 | May 26, 2020 @ 09:01 PM | 13,868 Views
Got a chance to fly the F2A Buffalo today. It's a little bit of a handful, but good fun, and FAST!
Durafly Brewster F2A Buffalo Maiden Flight [HobbyKing] (17 min 3 sec)

Posted by jmxp69 | May 25, 2020 @ 09:26 PM | 5,042 Views
This is the first look at the HobbyKing Durafly F2A Buffalo
HobbyKing Durafly Brewster F2A Buffalo PnP RC Plane First Look (6 min 53 sec)

Posted by jmxp69 | May 24, 2020 @ 08:48 PM | 4,934 Views
Here is the maiden flight of the Dynam Gee Bee Y Model:
Dynam Gee Bee Y Maiden [1270mm] RC Plane (11 min 51 sec)

Posted by jmxp69 | May 20, 2020 @ 09:06 PM | 10,603 Views
I got the Dynam Gee Bee put together and discuss what I learned in this video:
Dynam Gee Bee Y (1270mm) RC Plane Build Review (11 min 4 sec)

Posted by jmxp69 | May 20, 2020 @ 05:43 AM | 10,973 Views
This is the first look at the Dynam Gee Bee Y Model RC Plane:
Dynam Gee Bee Y RC Plane 1270mm First Look (13 min 12 sec)

Posted by jmxp69 | May 19, 2020 @ 01:38 PM | 10,341 Views
This is my new rocketship from HobbyKing:
HobbyKing Crusader 30E Maiden - ABSOLUTELY UNLIMITED POWER! Sunnysky x2814 1250Kv (9 min 36 sec)

Posted by jmxp69 | May 18, 2020 @ 01:01 AM | 6,264 Views
I got the HobbyKing Crusader 30E / Ugly Stik put together. This video shows how it went:
HobbyKing Crusader 30E [Ugly Stik] RC Plane Build Review (16 min 25 sec)

Posted by jmxp69 | May 16, 2020 @ 11:57 PM | 9,513 Views
Here is the first look at the HobbyKing Crusader 30e [Ugly Stik]. This is the built-up balsa and shrink covered plane, not the Durafly EPO plane with the flat bottom wing.

HobbyKing Crusader 30E RC Plane First Look (12 min 20 sec)

Posted by jmxp69 | May 13, 2020 @ 11:50 PM | 8,754 Views
This little Sunnysky motor packs a serious punch:
Sunnysky x2814 1250Kv Thrust and Power Test - This motor packs a wallop! (21 min 53 sec)

Posted by jmxp69 | May 10, 2020 @ 10:43 AM | 6,082 Views
After putting the Uproar v2 together I noticed the plane pulled hard to the canopy during knife edge and set out to figure out why:
Adjusting RC Plane Wing Incidence with Ailerons - Uproar v2 Tuning and T28 Updates (19 min 48 sec)

Posted by jmxp69 | May 08, 2020 @ 11:02 AM | 6,305 Views
DIY Perks has an excellent circuit design to provide a per cell voltage cutoff. You should watch that video first to get a visual reference of what I'm about to cover.

The little $2 LiPo voltage alarms available all over the Internet trigger an alarm when any cell connected to the balance lead goes below a voltage value set on the alarm with a momentary switch. You plug a battery in, then tap the momentary switch repeatedly until the per cell voltage level you want is displayed. At that point, when any cell hits that voltage, the alarm triggers.

This circuit uses that alarm to trigger a relay to open. The relay switch is inserted into the ground lead on the load. So when the relay closes, the circuit closes and discharging begins. When the relay opens, the circuit open and discharging stops. There are two poles on this "latching" relay. When an event is triggered on one poll, the relay closes and stays closed. When an event is triggered on the other pole, the relay opens and stays open.

The first pole on the relay is connected to the ground and pin 3 (cell 2) of the alarm. A 10 ohm resistor is added to the ground segment before the relay to drop the cell 2 voltage of 8.4 - 7.2 down to ~5v for the relay. A momentary switch is placed inline between the ground pin on the alarm and the ground pin of the relay for this pole.

EDIT: While troubleshooting, I took the 10ohm resistor out and just ran the wire from the 7.2v pin directly and it works...Continue Reading
Posted by jmxp69 | May 07, 2020 @ 01:30 AM | 6,089 Views
This is the maiden flight of the Tower Hobbies Uproar v2:
Tower Hobbies Uproar v2 RC Plane Maiden Flight (9 min 11 sec)

Posted by jmxp69 | May 04, 2020 @ 08:13 AM | 6,432 Views
This is the build review and live build of the Tower Hobbies Uproar v2. It is the first time I've done a video in this format. Usually, I do a build/assembly review which is an after-the-fact recap of the process or I film the entire assembly and call it a live build. This time I combine both approaches into a single video. So you can watch the highlights and stick around for the details if you want to see it go together and see my build tips as I go.

Tower Hobbies Uproard v2 Build Review AND Live Build (50 min 42 sec)

Posted by jmxp69 | May 02, 2020 @ 09:55 PM | 5,927 Views
In this video I take a first look at the Tower Hobbies Uproar v2 ARF:
Tower Hobbies Uproar v2 RC Plane First Look (15 min 42 sec)

Posted by jmxp69 | Apr 28, 2020 @ 06:22 PM | 10,153 Views
Your best bet is to take batteries to a disposal/reclamation facility. However, that's not always possible and the last thing you should do is just throw it away. The salt water trick isn't the answer either because that can merely corrode the positive/negative leads and leave voltage in the cell. This video shows how to completely drain a lipo. When you've completed the process shown in this video you can throw the remains in the trash.

How Fully Discharge and Kill a LiPo Battery (7 min 47 sec)

Posted by jmxp69 | Apr 27, 2020 @ 01:32 PM | 9,155 Views
Everything you need to make this is listed in the description on my YouTube channel. As built, it supports 3s-4s. For 5/6s I would want to add a step-down regulator to keep the fan under 20v. The discharger itself can handle 5/6s though:

Ohm's Law - A Practical Application: LiPo Discharger with per Cell Auto Cutoff (24 min 40 sec)

Posted by jmxp69 | Apr 23, 2020 @ 08:47 AM | 6,583 Views
Posted by jmxp69 | Apr 21, 2020 @ 06:27 PM | 8,166 Views
Almost Epic Portable LiPo Charging Station (4 min 9 sec)

There are enough "epic" charging stations on YouTube. Mine is just pretty good. This is the wrap-up on it. Here's what it can do:

- Dual Power Source - AC (120v) or DC (12-24v)
- Balance charge 2 6s5000mah packs simulataneously at 1c
- Discharge 3s-6s LiPo at ~1c
- Carry all flight batteries for a field day AND my 31,200mah powerbank
- Volts, Amps, WH monitoring via front facing LCD panel.
- LED Indicators for AC, DC, and Discharging
- USB Charges 2x devices up to 1.5a each

It is hard to give an exact dollar amount because I had so many of the parts and hardware already, but if you're interested in a cost breakdown, this should cover the biggest outlays:

Electronics - $153
$35 350w PS. Plenty of ~350w/30a options on Amazon near this price point.
$50 2x UP610 Chargers. I got these at a steep discount, but there are some Toolkit and ISDT options close to this price point.
$7 2x 2.5ohm 100w Resistors
$9 Heat Sink
$3 Step Down Converter #1
$4 Step Down Converter #2
$12 CPU Fans x3
$10 XT60 Connectors, Silicon Wire, Heat Shrink, Crimp Connectors, Solder (Shocking amount of 12awg silicone wire)
$6 LCD Panel
$5 LEDs and Resistors
$6 Power Distribution Blocks
$6 SPDT DC Rocker Switch

Hardware - $65
$30 Toolbox
$5 Wood deck
$20 Misc Hardware, Screws, Hinges
$5 3D Material
$5 Velcro, Wood Glue, Stain, Minwax Polycrylic

So about $220 give or take.
Posted by jmxp69 | Apr 19, 2020 @ 01:09 AM | 2,499 Views
Need a field charging solution with no AC power? This setup provides about 20k mah effective.
31,200 LiPo Powerbank in 5 Minutes (8 min 59 sec)