BCP upgrades = no lift  
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All Forums >> RC Helicopters >> Electric RC Helis >> E-Flite Helicopters >> BCP upgrades = no lift
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BCP upgrades = no lift - 5/19/2006 5:54:34 AM   
Kerberos32


 

Posts: 103
Joined: 1/17/2006
From: Vancouver, BC, CANADA
Status: offline 		Yesterday I had my BCP out, ran it for three packs, and managed to keep the spinning side up and out of harms way the whole time. I felt confident enough to get the aerobatic upgrade today. I installed the motor and heat sinks etc, however I left my plasi-blades on. Now I get no lift - at full throttle it will barely climb out of ground effect, and wont go any higher than about 2 feet. I thought the motor upgrade produced a higher head speed.

My BCP is modified with the Super Skids, e-flight aluminum swash, and the flat-bottomed plasti-blades. Its a little heavier than stock, however flew beautifuly with the stock motor yesterday. The blades are tracking perfectly, and there is just a very slight head induced vibration from a slight bend in the shaft. I gave the blades a couple of turns on the pitch control links to maybe increase pitch, but that seemed to lower the head speed.

What am I missing? Should I be using the symetrical blades? I thought the flat bottomed ones produced more lift. Do I need to upgrade to a lipo?

Peter

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There are old pilots, and there are bold pilots. There are no old bold pilots.
       Post #: 1

RE: BCP upgrades = no lift - 5/19/2006 6:03:35 AM   
Loswave


 

Posts: 504
Joined: 10/18/2005
From: Liverpool, NY, USA
Status: offline 		Keep in mind that a higher head speed will be because you sacrifice some torque, if anything you may need to decrease pitch, and a lipo is never a bad idea!

(in reply to Kerberos32)
       Post #: 2

RE: BCP upgrades = no lift - 5/19/2006 6:24:13 AM   
john68


 

Posts: 252
Joined: 1/20/2006
From: Burgettstown, PA, USA
Status: offline 		hmm...

stock is a 10 tooth pinion. I think the upgrade is a 9 tooth pinion. That would mean a lower head speed.

Think of it this way...

On a bicycle, the sprocket attached to the pedals is small, the sprocket attached to the wheel is big. If you make the front sprocket bigger, with more teeth, it will make the back sprocket spin faster. If you make the front sprocket smaller, it will make the back sprocket turn slower. Get out your 10 speed bike and try it.

The reason for the smaller pinion with less teeth is to make the head speed slower, but give the helicopter more torque and compensate for the larger voltage Li-Po battery ability to turn the motor faster. If you are looking for headspeed, get the 11 tooth pinion motor, but I dont' reccomend it with the heavy plasti-blades.

(in reply to Loswave)
       Post #: 3

RE: BCP upgrades = no lift - 5/19/2006 6:47:53 AM   
Kerberos32


 

Posts: 103
Joined: 1/17/2006
From: Vancouver, BC, CANADA
Status: offline
quote:

ORIGINAL: john68

The reason for the smaller pinion with less teeth is to make the head speed slower, but give the helicopter more torque and compensate for the larger voltage Li-Po battery ability to turn the motor faster. If you are looking for headspeed, get the 11 tooth pinion motor, but I dont' reccomend it with the heavy plasti-blades.


I'm just looking for get-off-the-ground-and-fly head speed. Will a lipo pack make 'er fly again? Should I ditch the plasti-blades for the symetrical ones? Or sould I just go back to the stock motor?

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There are old pilots, and there are bold pilots. There are no old bold pilots.

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       Post #: 4

RE: BCP upgrades = no lift - 5/19/2006 7:29:14 AM   
john68


 

Posts: 252
Joined: 1/20/2006
From: Burgettstown, PA, USA
Status: offline 		YEs, yes, and no.

or...

Yes, no, and no

or...

Yes, yes, and no.

or...

keep the stock motor, leave all the rest of the enhancement kit on, but go with plasti-blades.

OR...

keep the upgraded motor, put on the sym blades, and get a li-po, but save the wooden sym blades, and get the CF ones. I had about 4,000,000 crashes on my carbon fiber blades before they bit the dust. They are pretty sturdy, and are lighter than the plasti-blades, yet not as "indestructable." You won't break as much stuff with the CF blades, because they are not as heavy handed, yet they don't splinter like the wood ones will when you crash.

Just to get it back off the ground for now, I'd swap back to stock motor, and save the 9 tooth for when you get a li-po. Of course, when you get the li-po, you might want to downgrade to an 8 tooth pinion. Although, if you are looking for monster flight times of 30+ minutes, you could get the 1200 li-po, use the flat blades, and get an 11 tooth pinion, with increased pitch to about +15. Doing this will give you huge flight times, but don't plan on doing any aerobatics. That is how I have my scale Bell 222 Blade CP set-up. I have my aerobatic set up with the 9 tooth, 1200 li-po, bell-hiller, CF blades, and +10/-10 pitch... and... my stock Blade CP just has everything stock, except the stupid velcro battery attachment... I use small rubber bands.

(in reply to Kerberos32)
       Post #: 5

RE: BCP upgrades = no lift - 5/19/2006 4:27:06 PM   
Pilot352


 

Posts: 223
Joined: 11/1/2005
From: Chicago, IL, USA
Status: offline 		A few things,

I'm confused, the 3D upgrade’s main "advantage" is the symmetrical blades. If you kept the Plasti-Blades on, you basically just changed to a 10t motor only. The heat sink that comes with the kit doesn't add performance. So, what's the point?

Also, if you are not planning to cut the grass, why put the aerobatics upgrade on at all? By your message, it sounds like you are still in the learning stage. The symmetrical blades will perform with less lift than the flat bottom blades. They do, however, allow lift in inverted flight where the FB blades don’t. If you plan on doing 3d flying, yes, put on the symmetrical blades, but I read many who put the kit on thinking that they will get some huge gain in performance, when it's simply not true.

If you want to gain performance, go with the Bell/Hiller head upgrade first. There's a definite benefit there. Additionally, a three-cell battery has a higher voltage which relates to faster head speed. This is another major upgrade in performance. You get longer flights and higher head speeds. If you use the 10t motor with a three-cell lipo the motor might get too hot. I put two heat sinks on my bird with a 10t and a 1300mah 3-cell lipo and I find that it works great but the motor does run hot. I’ve only had to replace a main motor once and the tail motor three times. I get about 20 min. of flight time on a single charge. This is way better than the stock setup.

Pilot

(in reply to john68)
       Post #: 6

RE: BCP upgrades = no lift - 5/19/2006 10:14:37 PM   
Kerberos32


 

Posts: 103
Joined: 1/17/2006
From: Vancouver, BC, CANADA
Status: offline 		My goal in putting the aerobatic kit on was my understanding that there was an increase in head speed, hence greater lift. My BCP is a little hefty with the mods, so I thought this would help. I would also like to start trying some aerobatic maneuvers, loops, rolls etc. I realize the symetrical blades are for aerobatic routines, inverted flight etc, however I left the plasti blades on in the meantime until I was ready for the symetrical ones. Obviously I was wrong in these assumptions.

My point is that with the aerobatic motor, it should still fly - so what's preventing it from flying? I'm assuming that the combination of the super skids and plasti-blades is too heavy. I'm going to put the symetrical blades on tonight and see if it will fly better - (I can see the mass of the plasti-blades slowing the head speed), and if they work, I'll try the carbon fiber blades - as I really dont want to be constantle replacing the wooden ones.

I do have the bell mixer upgrade, and aside from replacing blade grips after every hard landing, its great. This coupled with the aluminum swash has dramatically improved the handeling characteristics. Before I put the aluminum swash on, the thing was increadibly jerky, and would constantly yaw left and right, no matter how much gain or trip I applied. That stopped as soon as I put the bell mixer and swash on.

Its a great little heli, I just wish I had held out for the pro version!

_____________________________

There are old pilots, and there are bold pilots. There are no old bold pilots.

(in reply to Pilot352)
       Post #: 7

RE: BCP upgrades = no lift - 5/20/2006 3:41:35 AM   
Crash Bandicoot



Posts: 138
Joined: 5/20/2006
From: Dayton , OH, USA
Status: offline 		Hey Kerberos32!

Did you go for the E-flite aluminum swash or another manufacturer? Did you upgrade the linkage too? I have seen a couple on the web but local shop has the blue E-Flite in stock.


_____________________________

I know of only one bird-the parrot-that talks; and it can't fly very high. Orville Wright - 1908

(in reply to Kerberos32)
       Post #: 8

RE: BCP upgrades = no lift - 5/20/2006 6:27:21 AM   
Kerberos32


 

Posts: 103
Joined: 1/17/2006
From: Vancouver, BC, CANADA
Status: offline 		Crash - I got the E-Flite aluminum swash, however I really want to get this: http://www.helidirect.com/product_info.php?cPath=30_65&products_id=1188 I just cant justify the cost purely for the coolness factor.

_____________________________

There are old pilots, and there are bold pilots. There are no old bold pilots.

(in reply to Crash Bandicoot)
       Post #: 9

RE: BCP upgrades = no lift - 5/20/2006 10:07:53 PM   
AJ DRAGON


 

Posts: 769
Joined: 9/14/2004
From: LAKEWOOD, WA, USA
Status: offline 		Hi

The aerobatic kit was designed to be used with Li-po batteries. I have the aerobatic kit also and I can tell you that in order to get the Blade CP off the ground with the symmetrical blades you have to use Li-po batteries. The reason the motor comes with a 9 tooth gear is so you do not burn it up when you hook up the li-po.

(in reply to Kerberos32)
       Post #: 10

RE: BCP upgrades = no lift - 5/21/2006 5:31:49 PM   
Kiiski


 

Posts: 51
Joined: 9/26/2004
From: Sammamish, WA, USA
Status: offline 		Exactly what AJDragon said,
The reason for the pinion change is to LOWER the head speed! The Aero kit is specifically designed to use 3s Lipo's, which are 11.1volts, the stock batteries are 9.6volts, higher voltage = motor rpm's increase, smaller pinion to keep head speed in check. The sym blades are great, even if you aren't doing aerobatics, the copter is steadier at hover than the flat bottoms and tend to balloon much less in windy conditions.
Kiiski

(in reply to AJ DRAGON)
       Post #: 11

RE: BCP upgrades = no lift - 5/26/2006 6:47:21 PM   
Skiddz


 

Posts: 89
Joined: 11/6/2005
From: Carlsbad, CA, USA
Status: offline
quote:

ORIGINAL: AJ DRAGON

Hi

The aerobatic kit was designed to be used with Li-po batteries. I have the aerobatic kit also and I can tell you that in order to get the Blade CP off the ground with the symmetrical blades you have to use Li-po batteries. The reason the motor comes with a 9 tooth gear is so you do not burn it up when you hook up the li-po.


Naw, I flew with the syms for months on the stock battery and stock motor. Never tried it with the 9T pinion tho. Now I run brushless with an 8T pinion and a headspeed of about 2100 RPM. Flies great.

Lower the pitch at full down. That'll increase head speed. Higher headspeed will allow you to run less pitch and still get the same amount of lift.

Having said that, the 3C LiPo really makes a difference, especially with the brushless main motor.

_____________________________

A helicopter is 10,000 parts spinning rapidly around an oil leak.

(in reply to AJ DRAGON)
       Post #: 12

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