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randall_l's blog
Posted by randall_l | Nov 30, 2014 @ 09:20 AM | 1,375 Views
We've been in the new house (to us) for a month. There's so much to do that I haven't unpacked or even organized the boxes in my 24x28-foot shop.

Heck, I haven't even been flying since early October. I'm either working, repairing, too sore to move or it's too dark out. It doesn't help that I now have to drive to the local park (instead of a quick jaunt across the street).

My TO DO list has never been so large. I suppose I've got some of the important things done--datacentre is up, video projector is installed, planes are racked. It does feel like home though and I guess that's what counts. My daughter loves the koi pond, my wife loves the hardwood and I'm elated to have my own workshop (though I wish it was insulated and heated).

It's -21C outside now and the furnace is working pretty hard to warm this old house. There's nothing like a brisk breath of 14C air to wake up to--kind of like a double-shot of espresso.

This build season is going to be put aside unfortunately. Too many high priority things to do to the house. So much for the new glider build.

Cheers!
Randall
Posted by randall_l | Sep 21, 2014 @ 03:46 PM | 1,302 Views
Got out for the maidens on the Fokker DR.1 and GeeBee R3 instead of eating lunch.

I flew the Junior to warm up and toodle around the sky a bit. Over 60 hours(and still counting) of slow-flying goodness.

Next, I tossed the Fokker DR.1 into the air... YES! A successful maiden and second flight. A couple circuits to trim and I started getting used to how it would behave to my input. The 3 ailerons that accompany Steve Shumate's plans for the DR.1 make it a very capable 3D plane. After I paint it and add a bit of weight to the nose, I think it will reside in (or near) my Grab-n-Go rack.

Then came the GeeBee R3... not so much. The first toss ended with a roll-left and nose-in. The second toss (more straight/level and less up) and I could tell from when it left my hand that it was tail heavy--boy, was it ever! I maxed out the rates and tried to get it down to the ground in one piece. The only damage was a crease on the bottom-front of the cowl.

I had used the CG from a similar sized (60mm shorter wingspan) and scaled it to my GeeBee's size. Obviously not even close. I'll try again once I add some weight in the nose to move the CG forward until it feels right.

Now, some lunch and time out of the sun.

Cheers!
Randall
Posted by randall_l | Sep 21, 2014 @ 11:33 AM | 1,367 Views
With the temperature beginning it's gradual decline, I'm starting to feel the itch of build season.

I've gotten a good deal of work done on the Gee Bee R3 (unpainted, but ready for a test flight), my third attempt at a Fokker DR.1 (also unpainted and ready for a test flight) and the Zero. I'm hoping to get some flight time in later today.

While at Target on Friday, I picked up an Air Hogs ZipWing and a Disney Planes (Fire & Rescue) Riplash Flyer (my daughter picked Skipper). Saturday was play day, so off we went to the park to meet some friends and play with our new toys.

The ZipWing is a piece of garbage--definitely not worth the $20 paid. The CG (Used Energizer MAX AAA's) is too aft and the plane is just too heavy to fly in general. My FF-DLG has the same wing area and is just under half the weight. I think I'll end up doing what others have done and convert it to 1S RC.

In stark contrast, the Riplash Flyer is awesome! $9 well spent. My daughter can only launch it about 6 feet, but it's a blast! She loves it--and I do too. Finding a way to keep my daughter entertained flight-wise for longer than 5 minutes just got a whole lot easier. I hadn't even thought about flying this morning, but before leaving for the park she said, "Wait! I have to get my airplane." I'd say mission accomplished.

Cheers!
Randall
Posted by randall_l | Sep 07, 2014 @ 08:14 PM | 2,023 Views
Today, the wife and daughter went in to town for a visit with relatives there for a wedding. That meant a day to myself.

First up was the Versus for 21 launches, totalling about 31 minutes of flight time over the course of an hour or so. I caught a couple thermals and even had an osprey join me until it decided that there was better lift elsewhere.

Next, I flew my new Extra 300 (based on RC Powers design) for a couple batteries:
Wingspan: 450mm
Weight: 61g (with Zippy Flightmax 1S 400mAh 30C LiPo)

After quick break for lunch and to charge some 2S batteries, I took out the Old Fogey (v2) and Junior until I needed another break.

Next up, I converted my pusher pod (2 or 3S) to a tractor and put it in the newly repaired MiG-7. After removing the bottom of the 3rd fuselage rib, the battery can be pushed farther back making the CG closer to where it should be. The re-maiden went swimmingly. It's such an impressive plane in the air and with the CG farther back, tip stall is greatly reduced. It was still very fast though, even on 2S.

After noticing some pink on my arms, I decided to call it quits and spend some time indoors. I definitely put more air-time in today than I had in the past couple months. Next summer, I'll stick to 5 8-hour shifts so it's easier to keep flying in my daily routine.

One last thing... when I went to put the MiG-7 back on my Grab 'n Go rack by the back door, I had to set it on top of the Old Fogey. It's a good thing we're looking for a new house. I'm going to need to increase the size of all my plane racks.

Cheers!
Randall
Posted by randall_l | Jul 11, 2014 @ 11:09 AM | 2,136 Views
It was really nice to get out for a few throws this morning.

I've really missed getting out for morning practice. During summer, my department works 4, 10's from 7:00 to 5:30. Shifting forward an hour means that I'm practicing in the sprinklers or in the end-of-day turbulent wind. I don't mind getting wet, but the sink associated with the cool wet ground is killer. And while flying in turbulence is good practice, everyday is too much.

It is however, nice to have 3-day weekends.

I've learned a lot from my HK Versus, but I'm looking forward to the upcoming build season (a.k.a. winter) where my primary project is the wings and tail set I purchased from DLGJunkyard and hopefully one of eitanro's fuselages for my birthday (August) or Christmas.

I started building another swappable this morning: a 556mm Fokker DR.1 (scaled to 60% from Steve Shumate's plans (36.5")). The pieces are cut out and I started engineering the pod mount.

This is my third attempt at a DR.1. This time I'm sticking as close to the plans as I can.

Later in the morning, I took Junior and The Fat Lady (Mustang) out for some fun. The Fat Lady is well dialled in now and attracted a fair amount of attention from passersby. If the temperature hadn't jumped up to 36C, I'd go out again.

Cheers!
Randall
Posted by randall_l | Jul 06, 2014 @ 06:57 AM | 2,352 Views
A friend's wedding was yesterday at a local school. Between the ceremony and reception (and after asking permission from the bride and groom), I flew my Junior (high-dihedral wing) in increasing winds.

When I started, the winds were 22kph. I had some doubts about flying--and normally I wouldn't in anything over 16kph. There was no one in the back field and after convincing myself that I'd had enough fun with this plane to justify a rebuild, I gave it a go.

I'm really amazed how well this tiny plane handled the wind. It was being tossed around quite a bit down below 20m, but remained stable. A shove in any direction close to 1m was not uncommon. After the first flight, a re-measure of the wind was 26kph. Since it was flying so well, I threw it again.

I managed to find a sweet-spot of stability around 30m above the school and turned the throttle off for some slope madness. I explored the bubble powerless for 16 minutes before I decided the wind was getting too much (I started losing ground).

Line up and approach was sketchy because of the turbulence caused by the school. After landing again a re-measure of the wind was 33kph. I don't have any other planes that I would dare fly in such conditions.

Thirty-eight-odd minutes of elation and much needed stress release. The Junior certainly held it's own and earned more respect for the folks who designed it back in 1946 (also gave me some high-wind experience).

Cheers!
Randall
Posted by randall_l | May 25, 2014 @ 04:31 AM | 2,362 Views
I've attached a marked up image of the park where I fly. It includes common wind directions and drops in elevation.

My goal is for this to aid in describing issues I have during flight.

Cheers!
Randall
Posted by randall_l | Apr 28, 2014 @ 01:35 PM | 2,807 Views
Another day another personal best, but let's start with yesterday...

I took advantage of the post-dawn still. In the morning, it's usually still before sunrise. As the sun rises, there's a gentle breeze (2-3kph) that pushes away from the sun. Then, calms down to another still spot before the prevailing wind kicks in. This leaves me with about 30-45 minutes of still.

The only breeze is from ground originating thermals--I've watched Osprey and crows take advantage of these and know where they start in my field (local park).

I re-trimmed the plane after finishing off the fine-tuning of my Taranis (followed the "Initial programming of a DLG" thread).

I added:
-a flight timer--reset by going into launch mode;
-a session timer--reset by going into launch mode while SD-middle;
-SH-up holds timers;
-variometer tones by SC-up;
-ALT read every 15 seconds by SC-down;
-ALT+ is read 4 seconds after leaving launch mode;
-telemetry is reset by going into launch mode with SD-down and SH-up;
-moved flaps to RS (so only rudder and launch mode require left hand--need to do this sometimes when my 2.5yo is with us at the park and my wife is deep in Mom-talk).

I did a few launches as I normally do... 19m, 20m. Then I started (for the second time) practicing recoil (Jun C's launch clinic on YouTube) and worked up to a fairly consistent 32m. I caugnt my second thermal sometime in my 8th flight and rode it from about 29m to 44m on a 2:41 flight.

Then when...Continue Reading
Posted by randall_l | Apr 19, 2014 @ 06:23 PM | 2,829 Views
As requested by my daughter, there's a new DLG in the house. Modelled after the FloW 5 (Fireworks 5 - flow).

The boom is a CF strip sandwiched between a split bamboo skewer. Feathers and pod are 3mm Depron. I used threaded rod for ballast (too much).

With a few tosses, I discovered that I'm going to have to lighten up the nose. I balanced it based on the more popular CG of the FW5, but it's way too far forward for this little free-flight bird.

Edit: I rebuilt the wing (wasn't happy with the profile or construction) and pod for my daughter's FF-DLG. Has less ballast and AUW is now 24.2g. I moved the pod back on the boom so that it goes right to the nose for impact resistance. Now it glides true.

Edit 2: Just had a moment of fatherly pride (that my daughter wants to do what I enjoy), so I thought I'd share. Her DLG won't look like that for long, but I'm sure she'll have a blast with it.

I've been going through the "Initial programming of a DLG" thread. My Taranis is set up to post 2. I did however add the following:
-a flight timer--started by leaving launch mode (with SH down) and reset by going into launch mode;
-a session timer--started by leaving launch mode (again with SH down) and reset by going into launch mode (with SH up);
-a read of Alt+ 3 seconds after leaving launch mode (with SH down).

SB and SC are what I'm used to for changing flight modes, so SB toggles between cruise, speed and float. I had swapped SF and SH previously (so that SF is the momentary switch) and use SH for throttle-cut, so it's a habit to flick it down before launch. I also use SF on powered models--especially my fast planes--for launch so it's a habit to hold it on launch.

Before the wind picked up (21-32kph now), I managed to get a single javelin toss in to trim the controls by way of modifying centre on the Servos screen.

With that, I'm ready to start paragraph 3 on post 3 (configuring the camber for other flight modes). Just waiting for the wind now.

Cheers!
Randall
Posted by randall_l | Apr 18, 2014 @ 09:35 PM | 2,757 Views
Well, last weekend was good--sunny and little to no wind.

I got the Junior 700, HK Versus and FT F-22 maidens done.

Junior 700 maiden:
I used the farthest back I could find CG scaled down from some Junior forums (51.2mm from LE) for the maiden. Pretty hairy flight, I'm glad I had flown my MiG-7 beforehand to juice up my reflexes. Managed to get it down with no damage.

I added ballast (about 12g) to the nose and that moved the balance point up to 42mm. Second flight was superb! If I were building her again, I would change the AoA of the horizontal stab to be a bit positive (LE above TE) to avoid having to trim so much down elevator. Thank goodness I put C bends in my control rods.

My wife was kind enough to get some video of my flights, so I'll massage them up and put them on my YouTube channel when I get a chance.

I flew the Junior to work a couple times this past week. It's definitely my new favourite. Super docile and definitely a floater--cruises at about 1/4 throttle.

HK Versus maiden:
I did a couple hand launches to get it trimmed, boy does it make my scratch-built mini ELF seem like a brick!

I'm still recovering from a sprained ankle from last July, but I gave a light launch and exceeded my full knacker launches with the mini ELF--and quadrupled the air time.

All I can say is, "I LOVE THIS BIRD!!!"

If I wasn't addicted to DLG before, I most certainly am now. The bad news (well, not really) is that my 2.5 year old daughter...Continue Reading
Posted by randall_l | Apr 13, 2014 @ 12:43 AM | 2,865 Views
So I had the opportunity a few weeks ago to assembly my swappable fleet for sort of a family photo. I thought I'd share it.

No mention of wind in the forecast for tomorrow so far, so I'm getting excited about some maidens: Prime Jet 8 (re-maiden); FT F-22; The Fat Lady; Junior 700; HK Versus are all waiting.

I've just started a swappable Bohm & Voss BV-141. Details to come soon.

Cheers!
Randall
Posted by randall_l | Apr 11, 2014 @ 10:50 PM | 2,859 Views
New member of my swappable fleet

Seeing spocktra50 (YouTube channel) fly around his Durafly Retro Series Junior, I got inspired. Based on Mark's videos and the threads here saying that the ailerons were fairly ineffective, I decided to do 2 wings: a high (24-degrees) dihedral wing with no ailerons; a low (12-degrees) dihedral wing with ailerons.

Introducing the Junior 700 (pictures attached)...
Wingspan: 706mm (high dihedral); 712mm (low dihedral);
AUW: 194.7g (high dihedral); 207g (low dihedral);
Pod: 2S pod

I used the Junior 60 (1955 reprint) plans from Keil Kraft (downloaded from Hip Pocket Aeronautics) for the build. The maiden will have to wait for the wind to die down, but I'm really excited about this one.

Other projects

My HK Versus is complete and waiting for maiden. AUW is heavy at 296g, but I'm using the excuse that it's my first kit.

The swappable Gee Bee R3 is mostly complete. There are a few pieces of skin to put on after I affix the wing and I still need to decide on a paint scheme.

Cheers!
Randall
Posted by randall_l | Mar 14, 2014 @ 10:07 AM | 3,892 Views
Measuring Thrust

I recently found out that the rig I was using for measuring thrust was very inaccurate. The postal scale that I scavenged from the recycle-bin where I work (with permission of course) was not accurate at all between 200g and 1kg.

So, I built a balance-type thrust rig and tested with a weight set. After determining that the new rig is out by 1.1g at 1kg, I started re-testing my power setups.

3S Power Pod:
Motor: Turnigy SK3 2122-2100kv Brushless
ESC: Turnigy Plush 12A Brushless w/2A BEC

2S Power Pod:
Motor: Hextronic 20g Brushless 2300kv
ESC: Turnigy Plush 10A Brushless 1/2A BEC

Batteries:
3S LiPo: Zippy Compact 3S 500mAh 25C LiPo
2S LiPo: Zippy Compact 2S 500mAh 25C LiPo

Propellers:
Prop 1: Turnigy Sport 6x4
Prop 2: APC style 6x4

Thrust (average of 3 runs):
3S Power Pod, 3S LiPo and Prop 1: 706g
3S Power Pod, 3S LiPo and Prop 2: 663g
3S Power Pod, 2S LiPo and Prop 1: 354g
3S Power Pod, 2S LiPo and Prop 2: 288g

2S Power Pod, 2S LiPo and Prop 1: 284g
2S Power Pod, 2S LiPo and Prop 2: 229g

1S Setups
AP05-5000kv Brushless, XP7A ESC, Eflite 1S 200mAh 30C LiPo
GWS 4540: 79g
GWS 5030: 92g
GWS 5043: 81g

With the results above it appears that the Turnigy Sport 6x4 is the better propeller for my purposes, but for a thorough comparison I'll have to use my watt meter.

Cheers!
Randall
Posted by randall_l | Feb 09, 2014 @ 06:51 PM | 3,304 Views
Let's see if I can make good on New Year's Resolution #3: Make at least bi-monthly blog entries.

I managed to get several projects completed over the past couple months.

Next, inspired by the Japanese indoor flyers (user: tyoukogatalabo on YouTube), I tried to build a sub 40g Pitts Special. Coming in at 34g and being very unstable, I added a hook to use on my daughters ceiling flyers (fishing line from a hook on the ceiling to a plane that goes around in a circle).

After that, I started working on a built-up wing with ailerons for my Mini Elf v3 and assembling a HobbyKing Versus. When I came to the realization that the servos I purchased for the Versus (recommended by HobbyKing on the USA warehouse version) weren't even close to adequate, I ordered more servos of different types.

During the wait time, The Flitetest folks released a F-22 with a bunch of improvements, so of course I couldn't resist making it a swappable, wingspan: 547mm, AUW 221g.

Still waiting for my orders to come, I got the hankering for another sub 40g attempt.

I decided (once again inspired by the Japanese indoor flyers) that I would build a mini Alula clone. As per usual, I added my own twist to the design with a KFm-2 airfoil and a swappable motor/glider pod. Wingspan 500mm, Glider AUW 32g/Motor AUW 37.4g.

I had to make a compromise against my principles and add 2.1g ballast to the glider pod to achieve the rearward CG. The motor pod is a bit nose heavy, but I'll see how it goes and maybe move the battery back.

Cheers!
Randall
Posted by randall_l | Dec 30, 2013 @ 07:58 PM | 3,181 Views
I've had enough time over the last couple weeks to get my P-51 Mustang almost completed.

I'll need to reprint the tail markings to the correct size (they were way too large on my initial printing) before applying them. I just couldn't wait to share some pictures.

The paint scheme is loosely based on Cripes A' Mighty. I had found an image of either a 3D or simulator rendering that had too much transparency on the invasion lines and thought, "Wow, that looks amazing!" So, I tried to emulate that using a mix of Tamiya acrylics (Titanium Silver, Chrome Silver and White for the light stripes; Gun Metal for the dark). I think it turned out pretty well.

EDIT: I found the image again here: http://www.352ndfg.com/vb/content.php?234 --didn't want to just upload the image in case of copyright infringement.

EDIT #2: The fuselage is 13mm wider than it should be for this scale (1/19) to accommodate the power pod. Part of the reason for the name. The other part is that I occasionally pilot well enough that my planes seem to 'sing'. (fat lady singing)

Specs:
Name: The Fat Lady (as in, "It ain't over until the fat lady sings")
Wingspan: 606mm
Airfoil: KFm7 (50/67/100/75 %)
AUW: 208.2g (with 3S 500mAh 25C LiPo and 3S pod)

I'll wait until the snow disappears to do the maiden. There's a layer of ice on top of the snow right now that chews up foam (even when covered with packing tape) pretty bad.

Cheers!
Randall
Posted by randall_l | Dec 21, 2013 @ 11:54 PM | 3,210 Views
Another night, another couple hours of 'insomnia time'.

This session yielded an ornithopter, thanks to Doreen Campervan's 'Make an ornithopter' video on YouTube. I only had to make some minor changes to get it to fly: add a second bend to the crank to even up wing movement; add a bushing to the front of the crank tube to smooth rotation; increase the length of the wing cranks to increase stability.

Construction materials are: bamboo barbecue skewers, cotton thread, 3mm basswood plywood, tube from can of compressed air, washer, 0.8mm music wire, carbon fibre rod, heat shrink tube, tape, gift-wrap cellophane, CA glue.

I had no idea how easy it was to create such an amazing machine. Weighing in at 10.2g, this 357mm (wingspan) engineering marvel takes it's place as the lightest non-paper aircraft I've made to date.

The gears are turning now... I can see several ornithopters in my future: pig ("When pigs fly"); monkey (Wizard of Oz); horse (Pegasus, from Disney's Hercules for my daughter); dragonfly.

My first goal is going to be an RC ornithopter, then progress to something like the beautiful ones in this video:
20121008SSFC SAFETYQuadcopter&Slowbirds (3 min 43 sec)
(starting at 1:14).

Cheers!
Randall
Posted by randall_l | Dec 20, 2013 @ 01:11 AM | 3,589 Views
Several airframes have happened since May, namely:
-Old Fogey v2(Flitetest Swappable);
-slightly-larger MiG-7 swappable(room to put battery inside the fuselage);
-Zazu swappable;
-Witch swappable;
-ultra-light 1S plane I call the 'Mosquito' (as in sounds like);
-KFm4 DavidWing (here on RCGroups);
-2x scratch-built KFm4 Assassin wings;
-FanJet trainer (here on RCGroups)--didn't last more than 2 flights;
-Prime Jet 8 (here on RCGroups, but made swappable).

Old Fogey v2(from Flitetest):
-tail feathers and front part of the main wing are 3-layers of 1mm Depron for increased stiffness;
-tail feathers strengthened with CF strip in the middle layer;
-main wing strengthened with 1mm basswood ply elbows and CF strip going right to the wingtip;
-nav lights on wing tips and wing/landing lights for night flying;
-nose strengthened with additional 3mm Depron and CF strip.
-channels: RET;
-wingspan: 585mm;
-AUW (with 2S pod and Zippy Compact 2S 500mAh 25C LiPo): 152g.

MiG 7 v2:
-tail feathers are 3-layers of 1mm Depron strengthened with CF strip;
-main wing is a 50% - 75% - 100% - 67% KFm7 airfoil with 2 CF strips which gives amazing full-size-like performance (based on footage of the MiG 3 and the ease of recreating the maneuvers) on such a small plane;
-aileron servo in each wing and a flapperon mix;
-channels: RETAA
-wingspan: 642mm;
-AUW (with 3S pod and Zippy Compact 3S 500mAh 25C LiPo): 183g;
-Using the HK Doppler iPhone app it was clocked at 92kph.

...Continue Reading
Posted by randall_l | Dec 17, 2013 @ 10:22 PM | 3,015 Views
I still owe an update on what's been happening since May, but here's what I've been working on the past 3 days...

A tricopter. I got inspired by the Mark and the gang over at spocktra50 on YouTube.

Specs:
Arm length (centre of frame to centre of motor axle): 150mm
Motors: hexTronik 20gram Brushless Outrunner 2300kv
ESCs: Turnigy Plush 12A Brushless ESC w/2A BEC (only one used for powering rx/servos)
Tail servo: Turnigy TGY-D1290P
Battery: Zippy Flightmax 2S1P 1000mAh LiPo
AUW: 226g

I had all this stuff sitting in parts drawers, so it didn't cost me anything extra. Of course, I'll have to buy some better props--likely 6x3 or 7x3.

The major setback however, is that the FY-30a that I had planned to use (also sitting in my parts drawer) is hooped. It still works fine for flight-stabilization but for fixed-wings only. The UART part isn't functioning anymore--I tried all the fixes for "USB device not recognized" that google had to offer.

I'll have to wait until I decide to buy a multicopter controller to get it off the ground.

On the plus side, it was one heck of a good time.

Cheers!
Randall
Posted by randall_l | May 18, 2013 @ 08:35 PM | 5,217 Views
I think I've just about got it now.

After hearing in one of the recent Flitetest videos about a swappable glider, I thought "I'm almost there already--just missing a couple components"

So during my mid-night waking times this past week and most of today, I set about finishing up the components for a modular mini glider platform.

I'm waiting for delivery of a XP7A 1S ESC and an AP05 5000KV brushless motor to finish up the motor pod. The AP03 7000KV brushless motor shown produces about 30g--way too little.

My next task this weekend is to work on assembling the mini vacuum form chamber I've been working and create the molds for covering the pods. I'm also waiting for some 3mm round x 1.6mm magnets to hold the pods on.

Once finished, the glider and motor pods are field-swappable.

Cheers!
Randall
Posted by randall_l | May 05, 2013 @ 10:13 PM | 3,955 Views
Well, I've gone and done it now...

I finished the build of the motor pod for my Mini-ELF v2. I made a micro JST (1.25" pitch) adapter with only signal going to the 1S 5A brushless ESC. The ESC plugs into the second set of battery pins for power. The battery powers the receiver directly.

Now for the time to test it out.

AUW is now 80.3g

The pictures show both the motor pod (installed, foreground) and glider pod (background).

Now I just have to come up with a method for easy field swap-outs. For now, I may just use a second receiver. It'll have to change once I get the skin formed and installed.

Edit: The motor is a HobbyKing AP-03 7000kv Brushless Micro Motor and the prop is a Plastic Folding Propeller Assembly 4.5x3.

Cheers!
Randall