Had my BCX three weeks, time to add ZING!

[singingperry]

Got pretty good with bcx, with a goal of upgrading to a Blade CP by end of summer I decided to quicken the BCX's control response. I moved the servo horn linkages to the center holes of the servo horns. Wow, almost seems like I'm starting over its so sensitive. If you do this be sure and adjust the length of the links as well as you can to get the trim as close to level as possible. With heightened control throw trim is more critical than ever. Then gradually ease into the throttle to see which way she's going to go and make adjustments to the links. Not having large hands and long thumbs, I found it difficult to properly move the control sticks on the transmitter during corrective-evasive manuevers, (YEEGADS, ITS HEADING FOR THE FRIDGE!)My sweaty thumbs were straining to keep a firm position on the sticks. I determined that the sticks were just too long. I unscrewed the knurled metal knobs off the sticks and with my trusty moto-tool w/cutting wheel I sawed off all but 1/4 an inch of the threaded portion of the sticks and screwed the knobs back on. The feel of the sticks were a lot more secure, less jerky. Pretty cool heli.

[singingperry]

What a difference a day makes, my heli really ROCKS! I'm circling the inside of my kitchen (12x12) sideways. When it heads for the walls I can bail it out easily with the heightened servo throws, and with the shortened transmitter sticks response is smoother and more precise. I'm getting too cocky for my own good but I have only snapped a landing gear post so far since I've had it. I'm REAL careful about flight times, avoiding heating up the motors and the4-in-1.Still don't have the heat sinks yet. Can't wait to get it in a gymnasium and cut loose.

[rocknbil]

Watch out for blade clash. When you horse it too hard even in the stock configuration the flybar dips down low enough to collide with the lower blades and they fly up and hit the uppers, causing the whole thing to fall out of the sky like a brick. :( With different servo mountings and shorter flybars it can get even worse.

There is a mod where you can extend the inner shaft about 1" that makes this go away. See you when you step up to the CP, the BCX teaches you a lot of *bad* habits that are difficult to unlearn on a CP.

[singingperry]

I'm intrigued, tell me about the bad habits, what they are, and the problems they cause when flying a cp. You're right about the blade strike, had one while workin it out (scooting around the floor) just to see how much I could jerk it around. Read about your great mods, any updates, best route to accomplish them?

[rocknbil]

I'm intrigued, tell me about the bad habits, what they are, and the problems they cause when flying a cp.

Well for one it's common practice to set the BCX on the ground, gas it up to a safe altitude and figure it out from there. The counter-rotating blades make it easy to do this. With a single-rotor heli,the counter-rotation is held in place by the tail rotor but also by the friction of the ground. When it lifts off, the friction is no longer there and this requires an adjustment of the tail right at takeoff. Try taking off this way wth a CP and the farthest you'll get is back to the repair bench (CRASH!)

The dynamics of a single rotor heli are such that when you take off, it will always drift to the left until it stabilizes. Most CX to CP beginners never see 6" off the ground for the first 5 or 10 flights. (CRASH!)

A single rotor heli will not hover on its own, even when perfectly balanced, for more than a few seconds. It requires constant input to hold a hover, for me it was harder to do this than to just fly around (and once I started flying, hovering became a lot easier.) It's like balancing a ball bearing on a piece of glass. Once the ball starts rolling, it will accellerate in that direction until you correct for it. Overcorrect (biggest newbie mistake) and it will go back in the other direction even faster. Give this a try. If you can't walk around a room and keep the ball bearing in the center of the glass, imagine what happens with a heli (CRASH!)

Of course the gyro and tail rotor are meant to keep the heil facing any given direction, but this is a lot more difficult than it sounds at first. Keeping the tail under control is one of the first tasks you have to learn, it's not the same as the lazy yaw of a BCX.

Another thing is the way the aileron/elevators work. When you go right, it's actually putting a little pressure on the REAR of the rotor, so by the time the heli gets the message it goes right. You have to fly "a little bit ahead" of where you actually intend to go, inputs are slightly delayed. This is another thing that makes hovering difficult - it starts to go left, so you push right, nothing's happening so you push right harder, by the time the heli catches up it now slams right so fast you jerk the stick left to compensate, back and forth . . . the result is you begin to "pendulum" back and forth until the ground stops you (CRASH!)

Last of course is "horsing" or jerking the sticks, which is related to overcorrection above. You can get away with sloppy flying on a BCX, if you get in trouble and just let go of the sticks it will re-stabilize into a hover. No such luck with a CP, if you let go of the sticks it's not only going to keep going in the last direction you pointed it, it's going to accelerate (BAD CRASH!)

I recommend anyone interested in a CP heli read The Electric Helicopter Beginner's Guide (http://www.swashplate.co.uk/html/ehbg.html
) cover to cover. then follow Radd's School of Rotary Flight (http://www.dream-models.com/eco/index.html
) before even considering lifting off.

Read about your great mods, any updates, best route to accomplish them?

The only mod you **really** need with a BCX is the aluminum head center shaft and heat sink. The lower aluminum head is nice but overkill really, it doesn't break very often.

My original thread and some mods (http://forums.radiocontrolzone.com/showthread.php?t=213115).
BCX onboard video (http://forums.radiocontrolzone.com/showthread.php?t=216849)
Best of the above thread is High flying BCX (http://www.rc-resources.com/images/testvid/high_flying.wmv) :D

By the way if you ever burn up a 4-in-1, they CAN be repaired, one poster's methods in this thread (http://forums.radiocontrolzone.com/showthread.php?t=209442).

[singingperry]

The first time I ever flew my BCX2 outdoors it was completely stock out of the box. No wind except for an almost imperceptible draft and it was a real struggle to keep from losing it to the fence line and the trees when the breeze came up. I also noticed the profile of the stock tail section made it difficult to rotate the heli against the breeze. I spent the following week making mods to the BCX. First I ordered the heat sink (don't forget the heat sink compound) and the aluminum inner shaft. Hadn't needed them yet but better safe than sorry. Once the parts were in it was easier to change them out than I imagined and it went together quickly. I also removed the 4-in-one unit from inside the plastic case and mounted the now naked unit back in place on the sticky pad where the case attached and lightly strapped it in with a cable strap,to help keep the 4-in-1 from overheating.(be sure to plug the wires back in the correct places).Next I took off the stock tail section and added a tail boom.I fashioned one myself as the E-flight carbon fiber upgrade was not yet available. I had previously moved the servo links from the holes at the end of the servo horns to the center holes (don't forget to adjust the length of the links by turning them)for a much increased control throw. After the mods were done I waited for a day when there was almost no wind, just an occasional light breeze but a fair bit more of it than when I flew the first time. With the increased control throws I was surprised how well the BCX now handled against the breeze, and with the low profile tail boom sideways flight and rotation were not nearly as difficult. Flight times in a light breeze were much shorter(about half) before battery power was low enough for the wind to push it around. With a fresh battery the heli gained altitude quickly, don't let it get above the treetops, the unhindered wind will yank it out of sight before you can say YAAAAH!!(it happened to me and its quite a story in itself) Descents must be gradual, the BCX just doesn't have enough power to yank its weight from a rapid drop and you'll end up bouncing it off the ground. One thing I can't stress enough, if you're in trouble with it, cut the throttle, from a high fall its far cheaper to fix any damage (you'll be surprised how much punishment it can take) than to replace a burned out 4-in-1 unit (now $59). Also, only fly it outside over grass or you'll scar it up for sure. If the wind pushes it toward the ground (skirting the grass) cut the throttle and let it tumble over. I did this a number of times without any damage at all, not even the blades. Once I wasn't quite fast enough cutting the power and broke a blade in the lawn, any slower I probably would have fried the 4-in-1. And don't fly on a freshly watered lawn, any moisture will find its way under the canopy into the circuitry and POWIE! Order plenty of spare blades (they're cheap) and have some fun!