Saturday, June 25, 2011

LED Nav Lighting DIY Tutorial

I've written about this subject before, but this diagram should help clarify how easy it is to add your own LED lighting for just a few dollars.
You can mix the type and number of LEDs as long as the total of the series is higher than 12.6V (assuming a 3S battery).
(CLICK DIAGRAM TO ENLARGE)
I use the thin wiring pulled from inside a phone cord. The wiring will only carry the tiny current drawn by the LEDs, so it can be very thin gauge.

You can duplicate the diagram as many times as you want to add more lights, e.g. one set of LEDs per wing. In that case, tap each circuit (of 4 LEDS) into the ESC battery connector, so they run in parallel.

I use Radio Shack's 10mm Ultra-High Brightness white LEDs, which is also a 4V diode, whenever I want to make one or more of the lights a landing light.  These big 10mm spot lights have a powerful lens that projects a perfect circle about 2 feet in diameter when measured around 20 feet in front of the airplane.  These lights are extremely bright for the negligible power consumption, and can be seen as an brilliant pin point whenever the aircraft is pointed at you in the air.  I try to angle my landing lights down about 3 degrees from level, so I have an intensity indicator when the airplane is established on the right glide path on final.
Landing light at the wing root, protected by the canopy
Finally, for enclosed Nav Lights that look realistic and provide excellent LED wing scrape protection, the plastic feet sliced off the bottom of an Aquapod work great.

Sunday, June 12, 2011

Two more Horizon Hobby safety warnings - one hazardous to you, the other hazrdous to the model

Horizon Hobby continues to find new ways to sneak acutely unsafe merchandise into the marketplace.

Today I had a model rocket off unintentionally, not realizing that the DX6i has no high throttle warning or refusal to transmit when turned on in bind mode.   I had become spoiled and lazy from using my non-Horizon, perfectly safe radios.

The second defect I found this morning was due to E-Flight's poor workmanship on the tail setion of their Champ 15e.  Those who read the Z8RC Champ 15e fixes might remember my remark that the empennage of that plane showed crinkled covering over awkward wood work.  As if to validate that superficial red flags usually indicate fundamental problems, I was lucky to discover that the horizontal stabilizer had become loose before Horizon incompetence destroyed another one of my airplanes.  The two embedded aluminum tubes that accept the wooden dowels from each half-stabilizer had become unglued from the structure behind the covering.   Another catastrophic quality lapse by Horizon Hobby.  


The floating nature of the tailplane was very well hidden, so all E-Flight Champ 15e's should be grounded until this critical safety check is accomplished.

Empennage construction is lumpy and awkward.  This critical flaw
proves that the poor craftsmanship isn't just skin deep.

Common Courtesy (obvious to most people)

Recently we've had a few of the moderators from wattflyer attempt to place personal attacks and clownish remarks on Z8RC; what they create everyday in their little cesspool.  The regulars here don't need to be told, but in case any more wattflyer moderators show up, realize that unlike watflyer, this site is actually moderated.

Intelligent and insightful commentary will always find its way onto my blog.  That assumes, of course, that one is materially capable of participating in an exchange of interesting and useful ideas.  Try it, after experiencing a little refinement and culture, not to be confused with having no opinion, you might like it better (not that I care if you do).

Z8RC is for civilized and objective, interesting and pointed RC commentary.  It is not a sales forum, disguised as discussion, where adolescents brashly peddle mediocre merchandise--like wattflyer pushing their cheap 3DHS  slap-togethers, or rcgroups hard-selling Horizon Hobby's brittle and acutely unsafe, mostly garbage product line.

Perhaps equally obvious: if you think your products need a covert advertising campaign to create the illusion that they carry reasonable value, then by definition, you think they don't.

This site's intelligent readership require better.

Saturday, June 11, 2011

A Record Setting Day

First, let me thank all of the bloggies who hit my blog yesterday, it was an all-time Z8RC record for unique hits.  Actually, yesterday obliterated the record. 

In other record setting endeavors, the Z8RC Champ 15e is getting nicely ironed-out. E-Flight tried to re-Christen the venerable plane the Ch-anvil, but we've managed to completely fix Horizon Hobby's latest binge of record-setting buffoonery.  With more than 10 oz of E-Flight lead removed, in the form of their half-dead-weight Power 15 and recommended 3200mAh stone to feed it, this Aeronca Champ finally flies like a Champion.  Video follows.

E-Flight's mistake configuration:
  • Motor:  Power 15 (5.4 oz)
  • Battery:  3200 mAh 3-cell (10.3 oz)
  • ESC:  45A (1.5 oz)
  • Thrust: 50 oz
  • Weight: 55 oz
  • Thrust:Weight ratio: 0.91
  • Flying time: 6-8 minutes
  • Stall behavior:  Severe wing drop to 70 degrees nose low
  • Maneuverability:  Poor
  • Float:  Poor
Z8RC 100% fix
  • Motor:  Super Tigre .10 (2.2 oz)
  • Battery:  1250 (4.3) + 1200 (4.1 oz) mAH 3-cell in parallel  (8.4 oz)
  • ESC:  30A (1.0 oz)
  • Thrust: 44 oz
  • Weight: 48 oz
  • Thrust:Weight ratio: 0.92
  • Flying time: 18 minutes
  • Stall behavior:  Mild shudder, no wing dip if coordinated, nose level recovery from slight sink
  • Maneuverability:  Excellent
  • Float:  Excellent
Stats for today's test flight:
  • Winds: 10 mph direct crosswind (note flags on takeoff roll)
  • Time aloft: 18:08 mins
  • Landing Voltage: 10.8V on final, 11.3V on taxi back
 
Read the annotations by clicking on the video 
to switch to youtube display.

    Thursday, June 9, 2011

    Unlimited Power

    There are different kinds of unlimited power, but only the lack of one kind will stop you from flying stone cold.  Even with 6 cells, 50% more than Spektrum's 4 cell NiMH pack, battery life of the Hitec Aurora 9 can be limiting.  For one thing, NiMH cell life is extremely limited in cold weather, but in warm weather I can still knock my Tx battery meter down  to 50%-60% after 2-3 hours of hard flying with the touchscreen light on.

    Enter the 6 cell 7.2V 4200 mAh NiMH C cell pack:
    NiMH and NiCd C packs can be very affordable, this one about $20
    Snip the Tamiya connector off and solder a servo connector on (no touching the high amp bare wires together!) and you're done.  I wrapped mine with heavy duty black shrink tubing for looks, and I notched the plastic battery door at the bottom a bit to let the NiMH pack wires escape the battery housing without stressing the plastic casing or the wires.  No changes are necessary to the NiMH recharger, as the cell count is still 6.   I have no idea how long it lasts, because after a full day of flying its still reading 90%.
    Held in place with 2" wide Industrial Strength Velcro.  
    The Tx is better balanced, too.
    After 2 hours of flying, this power meter won't budge.
    Another way to go is to buy a backup battery or two, but then you have to swap to charge two, and the life span together might still be less than a day.  Way better than one, no doubt.  No soldering required on the Tenergy version for Hitec users, as they put a Hitec compatible plug on by default.
    This one comes with a Hitec connector and costs about $10.
    For 4 cell radios like Spektrum, be sure to buy versions with only 4 cells.

    Tuesday, June 7, 2011