Plastic or Carbon Fiber main rotors

[SkyMaxx]

LOL...I have to chuckle to myself or more correctly, perhaps, laugh at myself. First, let me get this out of the way...be very, very careful with plastic or carbon fiber main rotors on helicopters of any size.

The long story...

I have had a Eflite Blade CP Pro for almost two months. When I bought the helicopter, I picked up a set of carbon fiber main and tail rotors to use "...when I got good enough..." Several wooden sets of main rotors and a couple of tail rotors later, I saw a set of plastic main rotors on the shelf at the LHS. I asked about them, and was told that one set would be more than enough of a replacement for the several sets of wooden rotors I had already destroyed. This sounded wise to me. I could save a fortune. The one caution I received was to be careful with them. They were very strong...and would no be as forgiving on the aircraft should they make contact.

That should have been stated more along the lines of "these things will cut your freaking arm off if given half the chance." No, I did not lose a limb, but I did manage to cut the tail boom off, twice. The first time was a mere boom strike. It looked like very little damage; however, the reality was that the boom was shattered from end to end. The second time, the rotor literally cut the boom off.

The plastic rotors? True to the LHS pro's word, they have barely a ding in them. In fact, I think these things could cut your arm off given the chance. I have heard that the carbon fiber ones are even more strong and lethal.

So...what's the moral to the story...wrench, run, break, repeat...LOL.

Actually, do be careful. Weigh the costs carefully both from a dollar amount and a time amount. The cost of the wooden rotors is cheap compared to the cost of replacing the tail boom for both dollars and time. Also, no matter how good you think you are...if you don't have an ass ton of time under your belt and you still have the training wheels on your heli...give real careful thought to whether or not you are good enough. I'm betting you aren't. Heck, I know for a fact, that I am not. Now, I just need to find where I put that spare set of wooden rotors.

Almost forgot...boom strikes can also f&*k up your motors. My main mysteriously burnt up on the first strike and the tail rotor motor seems to be toast after the second strike. There have only been three battery packs worth of flight time between strikes and while the main was the original and old motor, the tail rotor is only about five or six battery packs worth of flight old.

Sorry, no images of the carnage...forgot to snap a picture or two...but imagine trimming a tree branch with some shears...and you'll get the idea of what the tail boom looked like after the second strike...clean sheared off.

-SkyMaxx

 

[Rolex]

I did manage to cut the tail boom off, twice.

Sorry, Sky, but I laughed out loud when I read that line. I'm still chuckling, but fortunately it's at your expense.
Never give up the wooden rotors till you haven't done anything even remotely wrong in several dozen flights. Plastic or CF puts quite a shock through the whole system when something hits. A good hit will strip gears and bend shafts.
Until you really have it down pat, maybe you should consider casting your own rotor blades out of Silly Putty. Your daughters would love that.

 

[SkyMaxx]

Appreciate the moral support...you know right where you can stick that silly putty. Heck, if you do it right, you'll have two chocolate starfish instead of the one God gave you.

 

[Rolex]

Is THAT the thanks I get? See if I go out of my way to give YOU any more useless advise.

 

[SkyMaxx]

LMAO...and here I thought I was giving you some useless advice regarding the proper application of silly putty. =devil

 

[rocknbil]

....That should have been stated more along the lines of "these things will cut your freaking arm off if given half the chance."....

<snicker>

Sometimes ya' need ta' see it for yourself. I have seen the results of a big heli and CF gone bad - there's some pics floating around the 'net of a guy in AU who had his scalp peeled off. But he was back flying the next day, stitches and all . . . so it's all good.

 

[SkyMaxx]

Thanks for the link. Interesting read and sounds almost identical to my first two months of flying. Thanks to a third boom strike (3 strikes and they are out), the plastic blades go back into the tool box indefinitely.

The third boom strike was unavoidable do to a tail rotor motor failure causing out of control flight and a tail first landing from about three feet up. I was pissed. Freaking tail rotor motors...

At any rate, next trip to the hobby shop will be wooden blades, couple of replacement parts spares (tail rotor motors, tail booms, tail rotors, etc.) The next thing I will be doing if I stick with this bird, will be upgrading the chassis and motors to something a bit stronger and more powerful...or I will simply upgrade to a better heli, repair and sell the Blade along with its spares.

Again, thanks for the link...great information.

 

[rocknbil]

When you go to replace the boom, you may have some difficulty in getting it out of the frame. A heat gun and liberal amounts of debonder helps. I just replace the frame *once* and use just a DOT of CA. When you reassemble be sure to do this mod at the rear landing gear.

As for blades - you know you can repair them if they are not split completely, right? Or grow your own? Making your own takes significantly more time but repairing them is not as big a deal. You can splice in pieces of the leading edges with epoxy, then you cut a little fillet in the underside of the blades. Use short pieces of solder glued into these channels to balance them. Assemble a full head (you should have plenty of leftovers by now) and balance the whole head by hanging it by the flybar. Once repaired and balanced, you cover it with econocote or monocote and fine-tune the balance with bits of scotch tape.

At $17+ a pop for blades it's the only way I can afford to fly.

....unavoidable do to a tail rotor motor failure causing out of control flight and a tail first landing from about three feet up......

The second best mod you can do on a BCP/BCPP (first being the fuse mod) is to go with dual tail motors. It's not that expensive, although many are going with belt drives the belt drive is $200+ and the dual tail will cost you under $40. Not only does it make the BCP actually flyable by giving you complete tail control, if one of the motors goes out the other one brings you in. Additionally if you are using 3S packs, these little motors are not designed to handle 11.2 volts. A dual motor tail splits the load between the two (parallel wired) and makes both motors last like 5 times as long as a single motor.

OOPS forgot to mention - some guys are using paint stir sticks as alternative blades. Being a stiffer wood, these will have the same dangerous abilities as CF and plastic, just not as bad - but apparently with some sanding and balancing they work rather well.

 

[neobart]

How about some foam/plastic blades. They are cheap and soft enough to not leave your bird without a tail. I used them on my Walkera 36(basically a copy of a T-rex 450).

 

[SkyMaxx]

Link, please.

 

[write2dgray]

Great advice rocknbil, thanks!