Blade CP - how much damage is too much?  
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Blade CP - how much damage is too much? - 8/12/2005 6:26:39 PM   
-Rich87T


 

Posts: 4
Joined: 8/10/2005
From: Rockton, IL, USA
Status: offline 		I've gone through 2 sets of blades a replaced a main shaft thus far. Not bad all things considered.

Where do you guys draw the line with blade damage? Tape up torn wrap? Glue split wood? If you take a chunk out of blade, is it OK to cut a chunk from the other side and roughly balance them? Or do you just fly it until it won't take off anymore?

Where do you guys draw the line with replacing a bent main shaft? I picked up a wobble and vibration after eating some weeds so I replaced my main shaft. I've read about some of you guys dremeling it in half to get it out or deburring this and that... Mine came out with a pair of pliers and some pressure. How much wobble is acceptable? Can the main shaft be straightened? Replaced with CF or stainless? Seems like a set screw in the OEM gear and a piece of CF would be ideal...

FYI, when I replaced my main shaft, I left the swash (?sp) plate installed and removed the landing gear in one piece by gently working the four CF legs down. I had to remove the head, of course.

I've also found that after tracking the blades, if you 'balance' them the helo flys with alot less vibration. I add a 2" piece of clear 3M tape to the end of one marked blade then slowly run it up to bouyant. If the helo vibrates worse than while tracking, I remove that piece and put a piece of tape on the other blade. It seems to help, even if you use matched blade pairs.

I recently tried adding a piece of clear packing tape to front edge a new set of blades to see if i can protect them a bit better prior to having to repair them. LOL I haven't flown like this yet but they tracked and balance OK.

Thanks!
-Rich
       Post #: 1

RE: Blade CP - how much damage is too much? - 8/12/2005 11:05:34 PM   
Human_Enigma


 

Posts: 261
Joined: 7/25/2005
From: Seattle, WA, USA
Status: offline 		How much blade damage to fly with all depends on you. Look at it this way.. you approach the tip of the highdive at the pool, would you want to enter the water with your arms and legs spread out, mouth open and belly first? Or shape your body into the most aerodynamic shape possible as to create the least amount of drag on the surface tension of the water? Blade nicks happen sure, tho if your tipping it over alot, youve taken the training gear off too soon. Blade damage may seem minor though it only takes a little to set off the harmony between smooth fluid control, and impending disaster. I'm not saying that a heli is as complicated as a swiss watch, though they are not a frisbee by any means.. Ive heard of guys cutting the blades shorter, claimed it increased the head speed, though at the same time you lose " Control Surface". Its good to see that your interested in maintaining head balance whatever the means. Understand that a little shake.. when accellerated.. is " harmonic" Harmonic vibrations are distructive in more ways than you think. They can destroy bearings, rattle nuts and screws loose, Effect the gyro and electronics, stress fracture plastic, effect pitch.. and on and on.. Personally adding clear packing tape to the mains leading edge would only add more drag to them. not only that, think about it.. the thickness of the tape. relative to the scale of the model. umm lets guess the Blade CP is 1/20th scale.. VS. a full size helicopter. And the packing tape is 2.0 Mil thickness. What do you think a 40.0 Mil shelf top and bottom of a full size heli blades would do? Its a tuffie. And it all depends on what you want out of your little heli's..

(in reply to -Rich87T)
       Post #: 2

RE: Blade CP - how much damage is too much? - 8/12/2005 11:08:09 PM   
Human_Enigma


 

Posts: 261
Joined: 7/25/2005
From: Seattle, WA, USA
Status: offline 		oh and yanking the main out of the body section, you have to apply pressure on the inner race of the main bearings if you do so. This in turn can damage them. And could add to a source of vibration and binding if not replaced.

(in reply to Human_Enigma)
       Post #: 3

RE: Blade CP - how much damage is too much? - 8/13/2005 3:48:01 AM   
-pkh-



Posts: 2381
Joined: 5/28/2004
From: Emmaus, PA, USA
Status: offline 		Keep the blades balanced and try to match the CGs (some guys don't bother with that, though), adjust your tracking, and fly them if they still fly well, and if you are confident the blades (or parts of them) will not fly off in mid flight! If you get much vibration/wobble, replace the shaft... vibration is not good for the heli structurally, and it can screw up your gyro. In general, a vibrating heli flies like $h!t... so it's not worth skimping on the main shaft replacement IMO. If you're trying to learn on a Blade CP, you'll have a hard enough time with a perfect setup... why make things even more difficult for yourself...

_____________________________

Paul - Helis: Two Raptor 50V2s, Venture 30CP, Blade CX2
Planes: Twist 150, Twist 60, Tribute 36, GP .40 Mustang

(in reply to Human_Enigma)
       Post #: 4

RE: Blade CP - how much damage is too much? - 8/15/2005 5:15:58 PM   
-Rich87T


 

Posts: 4
Joined: 8/10/2005
From: Rockton, IL, USA
Status: offline 		Thanks for the replies. I'm 're-learning' after parking my fixed pitch lite-machine several years ago. I've had one serious "oops" out of 50+ flights and it cost $25 to replace everything back to 'out of the box new". I can afford a few more crashes and I've gone from crawling around to 4' hovering in the past two weeks. I replaced main blades 2x, main shafts 2x, a little rod that connects the grips and about 12" of rubber fuel line. Total <$50.00 in parts which is not bad.

I had very few problems expirimenting with the Blade as it came out of the box making 10-15 flights. My early problems came about when I replaced the main blades for the first time and my LHS told me to tighten the main blades until they are snug, to the point that if you tip the heli on it's side the blades won't swing closed. In 3-6 flights I bent 2 main shafts and broke a rod that connects the grips in a very mild "oops". I replaced all head parts and loosened the blades to freely swing again and haven't bent or broken anything in another 20-30 flights and several harder crashes. It seems like common sense that if the blade is fixed rigid and you strick the end, the head is going to take the grunt of the blow.

The packing tape doesn't seem to negatively affect the flight and has drastically prolonged the life of a set of blades. I used 2" wide clear tape about 4" long from blade tip to whereever 4" ends up. Folded over the lead edge 50/50 that gives about an inch of protection top and bottom. Taping the leading edge came about because I had a problem with the white plastic coating getting a front edge nick and then catching air and ballooning up.

I'm thinking the army should start wrapping the leading edge of thier heli's with thick tape and save a few bucks replacing them.

(in reply to -pkh-)
       Post #: 5

RE: Blade CP - how much damage is too much? - 8/15/2005 5:20:10 PM   
thecheatscalc



Posts: 1228
Joined: 8/13/2005
From: fayetteville, GA, USA
Status: offline 		i think they did in desert storm with duct tape....

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(in reply to -Rich87T)
       Post #: 6

RE: Blade CP - how much damage is too much? - 8/15/2005 10:43:16 PM   
Human_Enigma


 

Posts: 261
Joined: 7/25/2005
From: Seattle, WA, USA
Status: offline 		Right on, I'm glad the tape thing is helipng, do yourself a favor though and bite the bullet and get a pair of composite blades down the road, its amazing the abuse thay can take i paid about 40 bucks for mine. I screw my Blade in pretty hard from time to time, and they always seem to come out unscathed. As far as how tight the blades in the grips should be. Not completly loose, if they swing too easily they will " lead and lag " or swing to and fro each revolution and this in turn can cause a whole new set of problems dynamically in the rotor head, especially in forward flight. Rule of thumb, just snug enough for them to maintain their attitude in the grip but just loose enough to give if it hits the dirt.

(in reply to thecheatscalc)
       Post #: 7

RE: Blade CP - how much damage is too much? - 8/16/2005 6:38:54 PM   
-Rich87T


 

Posts: 4
Joined: 8/10/2005
From: Rockton, IL, USA
Status: offline 		Sounds about right. I may be on the "too loose" side of things then. I think I'm starting sift through the BS I was told at the LHS and the consensus here.

I was told by the LHS to wait on the carbon blades. They have a guy there that flies thier shop 'copter and he says he's cut two tail shafts, wires and all, in two with the carbon blades. He says, and i quote, "It'll fly better with the carbons, but when you crash, you'll break the expensive stuff instead of the blades." At $15.00 a pair for blades, it might be cheaper to break the head/swashplate. LOL This is also the same guy that told me to tighten the blades until they won't swing, too. Inital "cost" isn't really a huge factor to me, especially if it saves me buying 2 more sets of wood blades. If carbons are significantly better than the wood blades, I'll buy them tonight. If, however, carbons will start cutting tail tubes and breaking head/swashplate pieces like I've been told, then I'd rather stick with wood. Honestly, I think his problem is 1320 LiPo's on a 10T motor and over tightened carbon blades. But who am I to question the 'guru'? One last LHS quote, after replacing my blades for the first time... "We don't bother to track the blades. It'll fly fine".

All that chatter said... and considering the above average abuse of a newer flyer, do you still recommend carbons? Or will I really drastically increase the damage to the heli?

BTW, I'm not really shooting for inverted flight and stunts. I really just want to putz around competently and smoothly. I love the size of this heli and don't mind upgrading it a bit to improve fly-ability.

I'm still running the 10T w/ heat sinks, flat blades and stock batteries. I bought a Nicad/Nickle/Lipo charger but didn't drop the $$$ for Lipo's yet because I wanted to research those a bit more first. I'm thinking about buying carbons and switching ot the 9T from the performance kit. I didn't bother yet because I'm running stock batteries and thought the 9T would just slow the head speed.

Do you recommend 9T on stock batteries or stick w/ the 10T? I'm not ready to purchase LiPo's yet.

I do have one last stupid question. I bumped the rearend on some dirt/grass while hovering backwards and snapped the CF stick that holds the tail up, flush with the plastic. The plastic is not broken. How do you get the leftover CF rod out if there's nothing to hold onto? I was thinking about getting a small drill bit and hand reaming it out. Is it held in with CA, or friction, or what?

(in reply to Human_Enigma)
       Post #: 8

RE: Blade CP - how much damage is too much? - 8/16/2005 9:41:10 PM   
flaXen


 

Posts: 49
Joined: 8/16/2005
From: Riverton, UT, USA
Status: offline 		I wondered how much damage my blades could take, and I'm yet to find their limit hehe... My first flight was disasterous (yaw was wwwaaaaay off, and I didn't have my training gear yet...), but I'm still flying on my original blades. They've gained a few grams in weight, but they're even, balanced, and fly like a dream.

In the spirit of a speedy repair, I used replacement wood sections, fiberglass, and CA glue to reconstruct and resurface each blade. I've made one additional repair to the leading edge after my first repair. These things are much tougher now, but do crumple on-impact vs breaking other parts... I've also removed my flybar weights.

Also, make note of the nylon retainers on the fiberglass rod instead of those rubber hose pieces. Instead of losing those, the whole ping-pong and rod go flying and nothing is lost. I glued the outer retainer.


(in reply to -Rich87T)
       Post #: 9

RE: Blade CP - how much damage is too much? - 8/17/2005 2:32:38 AM   
Human_Enigma


 

Posts: 261
Joined: 7/25/2005
From: Seattle, WA, USA
Status: offline 		hmm interesting, Ive heard alot about all these blade strikes to the tail boom. not once have I ever had it even remotely close, though if your blades are too loose I can see how it would have the potential to do so if the blade had swung from perpendicular to the grip on the back side of the head during flight. Also if they were too tight and an abrupt landing did kick it out of plane but was too tight for the centrifugal force to swing it out true in time before hitting the tail. I have replaced my broken tail once( only because it was the first thing to hit the dirt practicing tail first passes and a tail turn at the top of the climb but thats all that broke after I lost it. ) and have even added a few degrees of uptilt on it to keep the tail from kicking up pebbles and glass all the time.
"Skip tracking the blades" , umm that is a joke.Track them. Balance them, The more fluid the rotor head functions, The better it will respond how it was intended Sure as with anything you upgrade, the hurt is just going to go farther down the line or the weaker link.. If you wreck, stuff is gonna break or bend reguardless. and your right as far as a 15 dollar pair of blades.. vs.. 6 bucks for a main shaft, or flybar, etc etc..
Flaxen seems to have a solution for his blade misfortunes, My hats off to his efforts, If your comfortable enough with having your blades look like that. Go for it.. As a new heli pilot, you wont notice the difference between " if it flies" and " how it flies" until you start getting into any agressive forward flying.
Tailboom stick : drill it out.. CA a new one in.. easy as pie.. need a chunk of carbon fiber to replace it? check out the kite shop.. if ya know the guy he just might give it to ya '_;

(in reply to flaXen)
       Post #: 10

RE: Blade CP - how much damage is too much? - 8/17/2005 2:37:37 AM   
Human_Enigma


 

Posts: 261
Joined: 7/25/2005
From: Seattle, WA, USA
Status: offline 		I believe all the reccomendations instruct you to upgrade the pinion with lipo's..And sym blades. but when I first got this thing.. I didnt upgrade the motor or blades and flew it with the lipo pack and had to set it down a few times to rest cause it flew so long.. I'm new this whole lipo battery thing but its good stuff.

(in reply to Human_Enigma)
       Post #: 11

RE: Blade CP - how much damage is too much? - 8/17/2005 3:14:07 AM   
Human_Enigma


 

Posts: 261
Joined: 7/25/2005
From: Seattle, WA, USA
Status: offline 		hmm for the life of me i cant seem to figure out how to post a pic in the message.. help?
I wanted to show a photo of how far out of whack the blade has to be to strike the tail boom.. its in my gallery for now..

(in reply to Human_Enigma)
       Post #: 12

RE: Blade CP - how much damage is too much? - 8/17/2005 7:29:54 AM   
flaXen


 

Posts: 49
Joined: 8/16/2005
From: Riverton, UT, USA
Status: offline 		Hehe ya... so the blade repairs aren't artistic, but function super super well.. Of the crashes I've had since adding the fiberglass, I shear more head/shaft retaining pins, but the damage done to the blade tips hasn't yet caused me to end a flight before my battery died.

I've had plenty of tail boom strikes. They leave a tell-tale digonal dent in my leading edge, but a little glue and sanding fixes it right up. On my last flight tho, a less-than-graceful landing snapped the tail fan's carbon shaft, but didn't damage the gear, blade, or motor. I was able to replace it with another piece of carbon and kept flying. I have more problems with faulty hardware in the tail than any other part of the Blade CP.

I'm thinking.... before I fly on my symmetric blades, I might tear off the plastic skin and replace it with carbon or fiberglass and epoxy (instead of CA) so I don't have to deal with such severe edge/tip damage like I had prior to making the above repairs. It does add weight, but lowers the overall "cost-per-flight", I'd say.

(in reply to Human_Enigma)
       Post #: 13

RE: Blade CP - how much damage is too much? - 8/17/2005 1:49:55 PM   
-Rich87T


 

Posts: 4
Joined: 8/10/2005
From: Rockton, IL, USA
Status: offline