Fixed Pitch Blade Tracking

I noticed that my CB180Ds blades were not tracking properly. When looking at the rotor disk on edge I could see that the blades were taking two separate paths through the air. I read online that fixed pitch (FP) helis need their blades to track properly, just like CCPM helis. I also read that by putting a piece of white electrical tape on the end of one blade (small enough not to cause a gross imbalance) I could see which blade was tracking high, and which was tracking low. It really worked. I also read on this same link that placing a small piece of tape at the blade grip would change the blades pitch and bring the blades in line. I had to chose to either bring the high blade pitch down, or the low blade pitch up. I arbitrarily chose to bring the high blade down. I found I had to put a piece of tape in front of the bolt on top, and a piece behind the bolt on the bottom, tilting the blade forward reducing the pitch. This levered the blade so the leading edge pitched down. On spin up the tracking was spot on! (See this link on RC Airplane World:

http://www.rc-airplane-world.com/rotor-blade-tracking.html

Windy day, so I hovered the CB180D in the Man Cave for one pack. With the mixer set up for in flight as opposed to hover stabilty it was still easy to hover, but I couldn't take my eyes off it for second. Can't wait to see what happens when I can let her run. If it doesn't improve her handling in flight, I will bring them to the middle, balanced for hover and flight. (See this thread on the subject of bell mixer set up on HeliFreak:

http://www.helifreak.com/showthread.php?t=258027

Beautiful day to fly!

Went out on this beautiful, calm day.

The CB100 loved being able to run, but just isn't an outdoor cat.

The CB180D is pokey too.  It seems to have good headspeed, but it just has no go. Even in light winds today it got pushed around. The stubby servo arms are not adjustable and I maxed out the extent on the receiver. It just isn't fun to fly as it just gets swept away. I found some longer servo arms at WowHobbies and ordered them. I don't want to do an all brushless upgrade as it makes it a direct tail drive, and costs as much as the heli did. Hopefully the longer servo arms will do the trick. I think the spline on these servo arms might fit the CB100's (wouldn't that be great)! Well, that pokieness lead to a loss of control and a broken blade. I tried just replacing one, but the vibrations were too great. Replaced both and it balanced out nicely.

Realized that I am waiting for the new guide set for the UFLYS, which DirectHeli has just mailed me (sending me the parts for free!), before I can fly it again. No flying for you!

My CB100s Seizure disorder

Video of the Seizure disorder suffered by my CB100 #2...



One of my CB100s developed a seizure disorder, where it would literally seize, fall from the sky, sometimes coming back to life in fits and starts. The issue is not the mesh, or the motor. I suspect the receiver, as the tail rotor appears to be affected at the same time, suggesting the main motor ESC and the tail ESC are not the culprits. The receiver is a stock Walkera RX2406C.

UPDATE: Well... I wanted to see if it was the receiver, so I swapped the bad heli's receiver, and the motor ran the same, so it's not the receiver. When I put things back the way they were supposed to be I noticed that one of the 3 pins in the plug from the main ESC to the motor was back further than the other two, so I pulled it forward. I squished everything, and would you believe the problem is gone? Sort of. After some hard landings it returns. I squish everything, the ESC, the receiver, the plugs, and the problem is gone. Its a loose connection somewhere. Flying this heli is smooth like butter... tuned and trimmed, locked in. Very nice!  I have a soft spot for the twins.

My Newbies Advice

I posted this in a discussion on Helifreak.com and think it bears repeating here.

Hi,

I too just started last month, and am having more fun than I could have imagined. It has not been all happiness and joy, but all in all I am wholly addicted! A couple of recommendations from my own newbie experiences, so fresh I still have that "new pilot" smell and consider it an achievement when a heli goes up, stays up, and comes down in one piece for just a few seconds.

1) Visit with those folks at (your local flying club). Just walk right up and introduce yourself. You will be welcomed and encouraged to enjoy yourself asking questions, and maybe even find that mentor you are looking for. I wish I had a mentor, and hopefully after tomorrow's local club meeting I may have one.

2) By the Esky Sim kit, download the latest version of the free FMS RC Flight Simulator (Google both, easy to find. When you buy the Esky kit, really you are buying the controller as the FMS on the included CD is a bit dated). Have fun with it. If you think this is going to stick, buy Clearview RC Flight sim. Better graphics and more realistic flight (albeit still way stable) for a very reasonable price, with great customer support from Stefan. You can use the "transmitter" that comes with the Esky kit. I LOVE this sim, rather than the ones costing several hundred buck, which I am sure are more realistic and quite nice. Like others, I cannot overly stress how important sim time has been, continues to be, to my flying success and confidence. DON'T GET DISCOURAGED! Keep practicing on the sim, and you will be surprised how quickly you learn. Work on hovering tail in, tail out, circles, orientation, etc. I do it over, and over and over again.

3) There are lots of opinions about first aircraft out there, and really, they are all good ones. It just depends on what your resources are and how you want to approach this great hobby. I wanted to start inexpensively with helis that were easy to fly, and for which replacement parts were easily available. I watched several reviews at xheli.com, and many, many vids on YouTube, read reviews, and asked questions on forums like HeliFreak. I decided I liked the idea of buying a nice fixed pitch electric like the CB180Z as a starter. Any similar one is likely to be fine. (I really don't like the tail situation on the UFLYS, but it is a really nice heli). It won't hurt so much when you crash...

I knew nothing about RC helicopters, other than they fascinated me. I was afraid of flying them, breaking them, being unable to repair them. I have learned not only can I, I love doing it all! Most of all, its fun being part of a community like local flying clubs, and HeliFreak. My wife, on the other hand, never sees me anymore...

Enjoy!


I would now also add Radd's School of Rotary Flight at
http://www.dream-models.com/eco/index.html

Radd's School of Rotary Flight

Wish I had known about this before...

http://www.dream-models.com/eco/flying-index.html

UFLYS is ready for flight/trim testing

The UFLYS is ready for flight and trim testing. The tail shaft power take-off pinion seems to be in its happy place. I did some spin up today and it engaged well. During spin up when it got light on its feet if veered off so I know it needs trimming (I thought the 3x gyros did some of that...). It is too windy and gusty outside to hover it to check the trim, so that will have to wait until tomorrow when hopefully the weather will improve.

So here's a pic of my repaired, ready to fly (LOL) UFLYS!

3 of 4 up!

Took the CB180D out for 2 packs, but the gusts just carried her back despite full forward pitch, so I brought her in. I am very pleased with how I controlled her, in all orientations. The flight sim has, and I say this a thousand times, made all the difference. I actually have started doing inverted flying on the sim, gearing up for the CCPM I hope to get after Christmas! Ha! Even if I do it will be a loooonnnnggg time before I do anything other than scale flying.

Got both CB100's flying today! All trimmed out and upgraded. All I need is upgraded main motors. #2 has a stock 2 gm motor, but a new fin, thicker carbon fiber. This is the one with a solid carbon fiber boom I made from the old UFLYS tail shaft. That's why the wire is wound outside. I still have a problem with #2 occasionally just stopping mid flight and falling from the sky... Bad receiver? #1 has an upgraded 2.9gm tail motor with a new fin, a new tail boom (stock).

The CB100s fly well, but remain underpowered. The trim on these bad boys goes wacky with every hard landing... I think my next upgrade is hot rod main motors. I still haven't opened them up and let the fly hard, just no room inside. Soon the weather will be calm enough to take them outside and let them run.

The Twins, my CB100's

New 2.9 gm motor and fin from WowHobbies. Nice soldering and install if I do say so myself!

New 2.9gm from the hot side

New stock 2 gm with new upgraded fin. External wires around the solid carbon fiber boom.

New stock 2 gm motor and new upgraded fin. Another nice install!  I am getting the hang of this.

The naked UFLYS. Replaced the tail shaft inside the boom, and the stock tail shaft power take-off pinion. Took a couple of tries, but I think I may have solved the tail shaft pinion issue. I ended up using CA to secure the pinion on the shaft as it meshed well but spun on the shaft. Will find out tomorrow, don't feel like dealing with it anymore tonight so I didn't spin it up after the CA.  If she engages consistently (I am not sure yet, had to take it apart twice during this repair after it seemed to work, but then didn't) I hope to fly her soon.