March 2009 Archives

1 Year review - Parkzone - Citabria (Kyosho Minium Citabria)

| Comments (0)
I have had my little Parkzone Citabria for 1 year now. I figured I'd write up another review, summarizing the good, bad and ugly.

citabria_stand.jpgHere are some highlights:

Bought: March 15, 2008
First flight: March 17, 2008
First grounding crash: March 17, 2008 (broke prop shaft after flying into wall)
Total flight time to date: nearly 13 hours
Number of flights: too many to count
Experience level required: little to none
Recommended extra bits to buy: extra battery (maybe check out 110mAh version), extra props (get at least 2, you're gonna break the shaft and will not be able to reuse the prop), scotch tape (needed to reassemble after oiling the motor and for quick, cheap field repairs - alternatively you could purchase expensive foam safe CA and kicker, but you'll still need the tape to put the top and bottom back together)
Total cost to date: $195 (Cdn, plus taxes, etc)
Biggest complaint: weak prop shaft (if you have not broke your shaft, you will - be prepared)
Best feature: 2.4GHz radio (feel to fly nearly anytime, almost anywhere)
Suggested improvements (other then poor prop shaft): upgrade radio to DSM2 compatible (Bind-n-fly) system, provide better charging options (would like plug charger in and not use expensive AAs)

The Good
Out of the box and into the air in less then 15 minutes! For a Christmas or birthday present to someone seriously interested in flying RC planes, you cannot lose. The plane comes with everything needed - and I mean everything - even 8AA batteries to run the Tx and power the LiPo battery charger (yes the plane also comes with a removable LiPo battery). This plane is probably the simplest of all the real RC planes on the market. By real, I mean radio based Tx/Rx, removeable battery, minimum 3 channels. This is not a toy given to a 10 year old to crash around the living room with.

Easy to fly - if patient. Find a friend who knows what they are doing to fly it first and ensure it is trimmed and working correctly. Then find a large area with no wind. High school gym (full basketball court) is about as small as I'd recommend. I started in an elementary school gym (slightly larger then a full volley ball court) and those walls come quickly when you are new! This plane flies slow and gently enough that if you are outdoors and get confused, just cut the throttle and let go - it will gently glide in for a soft (if maybe nose in) landing. Within an hour most people should be comfortable enough with its flying characteristics to move indoors or to a smaller gym. I can now do figure 8's in a space about 30'x60' (10x20m).

Full proportional 3 channel control. Throttle, elevator and rudder. You are learning to fly a real plane and have nearly all the control required. Learning on the Citabria provided valuable experience I was able to transfer to my larger sailplane and hopefully on to a 4 channel this summer.

Removeable LiPo battery - this means you can (and should!) buy a second battery and swap them once the first one runs out. With fresh AAs in the charger and some throttle management (flying at 50-60%) the charger was able to keep up and with only 1 extra battery I never had to wait for the battery to charge. The battery is compatible with the MCX helicopter 110mAh battery, and the extra weight is negligble. I'm not sure but you may have to stick some velcro onto the battery to attach it to the plane. The 110mAh battery should increase flight times to over 20 minutes on one charge!

The 2.4Ghz radio. The good is that the 2.4GHz radios are virtually glitch free, do not interfere with each other (practically speaking - you are limited to 20-25 planes in the air at once) and use relatively little power. After 1 year and many hours, I am still using the original AAs in the transmitter. (The charger is a different story.)

The Bad
Not necessarily bad, but limiting and good to be aware of: The plane is Very light (by design) which requires either perfectly calm winds or moderately large indoor flying location. It is fast enough that you will not fly this inside your living room or even garage (unless you have a 10,000 sq ft garage...), however it is light enough that even 5-10km/h winds will be bothersome. This limits when and where you can fly.

Despite being modelled after the Citabria (Airbatic) it has limited acrobatic capability. Again, this is by design, but after a year of flying, it does get a bit monotonous. While I have done some inverted flying (after increasing the elevator throw to its maximum setting), this plane is pretty much stuck flying the pattern and doing the odd loop. After a while, you will probably be looking for something more advanced, which leads me to the next concern.

Radio - in spite of being 2.4GHz, the Parkzone radio system is not an industry standard. You cannot use the transmitter with other receivers and you cannot use your Spectrum or Futaba 2.4GHz transmitter with the plane. This means that unlike the Bind-N-Fly series of planes and helicopters, you are forced to buy, get used to and power yet another transmitter. If this is your only plane, it is a moot point. However, if you are planning on expanding into the hobby or thinking of adding this to your collection for those lazy summer evenings in the back yard, then it's an extra cost that should not be required.

After flying for nearly 13 hours (12hr 48' as of March 16th 2009), the original LiPo battery is not holding much of a charge. I'm not sure if this is because I have put too many charge/discharge cycles (doubt it, with the 2nd battery, there is less then 50 cycles on the battery) or because the battery has reached the magical 2 year life span LiPos are know for (maybe, although the plane has been around that long that the shelf life should be an issue) or maybe its just not a good battery. Flight times are down to 5 minutes or less. This is a relative comparison as my plane has lights powered by the battery and the overall wear and tear on the plane is most likely also contributing to shorter flight times (drag from dings, motor wearing out / getting dirty).

(The 2nd battery I bought is still giving me 10+ minute flights.)

The Ugly
Poor design of the prop shaft. The shaft is threaded, which creates a weak spot that will break during a hard crash. I had 2 shafts break, and neither were exceptional hard crashes - in fact, since finding a better (and cheaper) way to repair the damage I have had much harder crashes without damage. The first was into a gym wall - which sounds harsh, except it was not direct. I flew along the wall, the wing snagged something and the plane spun into the wall breaking the shaft. The second was in an indoor soccer arena where I became caught up in a net about 15' (5m) above the ground and did a nose dive onto the hard, but rubber coated surface. Replacing the shaft Parkzone's way involves replacing the entire motor assembly which means breaking it free from the glue holding it to the foam body and soldering very thin wires. By simply enlarging the hole on the new prop a little bit and friction pressing the prop onto the shortened shaft I have had no problems!

Smoke reducing solder station desk lamp hack

| Comments (0)
I've been wanting a better lamp for my work bench to provide better lighting while soldering. In my mind I was thinking of some type of long articulating lamp that gets clamped to the table. However, when the other day wandering through my local Wal-Mart, I came across a curiosity. It was a small halogen desk lamp with MP3 Speakers! (oooh, mp3 speakers, but no amp - huh?) Anyway, I guess they weren't quite the hot seller Wal-Mart hoped and the $29.97 lamp was being cleared out for $10. Yay!

I set it up and it worked great! But then I had an epiphany - the bulb is 12V, I have surplus 12V computer fans - this lamps would rock so much better if I had a fan to draw the solder smoke away from me, so why not tap into the 12V lines and power a small fan!?!? I'm a genius!


So I open up the lamp, and took stock of how Maker friendly / hackable this unit is. Turns out to be very friendly. Regular philips screws holding the bottom on.


A large nicely labled 12V transformer and crimp style marrettes connecting the lamp to the transformer. (Note the speakers - those may come in handy somewhere.)

The marrettes are easily re-used by gently pinching them open with pliers - just squeeze the sides of the crimp to open.

The bulb is current direction agnostic, and so no diodes or rectifiers were supplied. No worries, I spliced a small diode in line with the connector.


Initially I was going to have the connector at the back, but failed to take into account the extra mounting plastic. So it ended up coming out the front.


A bit of CA to hold the connector in place and reassemble the base and we're done!


The original idea was to use a small 2" fan, but that didn't draw the smoke away well enough, so I went for the larger case fan.


Much better!

Some other bench hacks / improvements:


Copper cleaning pad instead of fussing with sponges that are forever dry (I don't solder every day).


A large analog multi meter whose dial broke has been permanently set to the 10A current setting (the A or A/2 switch still works) and wire in series with the AT power supply. Its hard to see, but there is a toggle switch burried in the wires to select the 5V or 12V bus to monitor. These wires power a light and some fans to keep the power supply happy (hence the 1A reading), then they are off to banana plugs, AT power plugs and a cigarette lighter plug for bench use.


Finally the whole setup - power supply, soldering station, bench lamp, soldering lamp/fan combo - is all powered off a single power bar. One switch to shut it all down for the night!

Thanks for stopping by - hope something here inspired you to make your bench more functional. Leave a comment to let me know what you've done!

Germans lost again...

| Comments (0)
This time it was my fault. The plane was too big for the golf dome and me. I should have waited for a sunny afternoon and taken it outside (where I can get up at least 3 oops high). There was one short flight that ended in a stall, bank to the left a dive and a hard landing. Less then 1 minute in the air.

Fortunately, the damage is minimal.


Right tire is broken (as predicted on many forums).


Some (hard to see) internal damage to the trailing edge along with some separation of the skin.


And a broken tail - this happened in my house when I accidentally reversed the throttle channel on my Tx. That is very scary!

All in all, should be quite repairable and when that sunny afternoon comes round, I shall be back.

New plane! Lanier Fokker D.VII ARF

| Comments (0)
I have a new bird to fly! A Lanier Fokker D.VII ARF. Follow the flights on its own page!

Purchased the airframe at a swap meet. Had a couple servos at home, bought 2 batteries, motor, ESC, receiver, 2 more servos and some odds & ends to get this bird ready for the air.

From Hobby King:

SKU Description Qty
TPC>5-2-1047 TowerPro BM2410-9T / 18A BEC/ 1047 1
TR-5011 Turnigy 2-3 Cell Lipoly Balance/Ch 1
Ec1300-20-3 Zippy-Ec 1300mAh 3S1P 20C Lipoly P 2
HD-1550A Power HD Servo 5.5g/0.9kg/.10sec 2
AM-2005-M-60 60cm Male 22AWG Twisted 2
RP6D1-72 Corona Synthesized Dual-Conv Recei 1

Looks sharp!

The receiver is an interesting animal. No crystal. It scans for and locks onto the first 72MHz transmitter it finds. Once setup, it remembers the channel and is good to go! Being a six channel receiver, I have configured the plane to use flaperons. Will be interesting to see how well that works out!

More details to come!