Test Fly Wobble and Balancing 4 blades?

Uglybob · 07-28-2012, 11:41 PM

Hi,

I did a test flight on my EFL Pro with an Align 4 Bladed head and while the heli flew and wasnt bad to fly.. there was a very noticable wobble where the skids would vibrate from left to right about 20-30mm.

The blades are balanced but only with its opposite blade(in pairs).. not the whole set. When I got home I went to balance all 4 but the two pairs are way out of balance. My scales show they weight the same each, 51g, but wont balance on the blade balancer without a huge amount of tape.

Would this cause the wobble... i figured having the pairs balanced should be enough.

Uglybob · 07-29-2012, 12:40 AM

I loosened the blades a little since the lower head speed wont be able to move the blades in the grips as easy and while it was helped... it hasnt eliminated the issue.

treotraveler · 07-29-2012, 08:57 AM

It's my guess that you used the original efl flybarless pair, and bought another pair? If so, is the other pair flybarless blades also? Are all four blades in track? Are the blades loose enough in the grips to stretch out when spooled up?

Cap231ex · 07-29-2012, 10:07 AM

It's your tracking it has nothing to do with the blades themselves or your blade grips being to tight or to loose.

Check is at mid stick with your motor unplugged with a digital pitch gauge , all blades when measured at the same place usually at the front location should be the same pitch.

If done correctly this will stop your wobble issue.

Uglybob · 07-29-2012, 09:38 PM

First set of blades I tried where scale carbon blades from RCA. They tracked fine and were setup properly. Loosing the grip on those seemed to help too but didnt go away.

I then tried 2 sets of the EFL Pro blades from Align... initially the tracking was way out for 1 blade and we went through and res setup the pitch on all the blades and the are all within 0.5deg of each other. In the air the tracking looked fine and once again, loosening the grips seems to help some.

My next option is to test the CoG of all the blades and make sure they are correct and rebalance all blades so they are all equal. Going to take a while to do but may be needed.

Uglybob · 07-29-2012, 09:39 PM

https://www.scaleflying.com/New-Item...s-_p_2439.html

These are the blades I used... they are sold in a set of 4 but are just 2 matched pairs.

Christopher J · 07-29-2012, 10:21 PM

Whats the headspeed? Some scalers with multis are "picky" on headspeed.

Uglybob · 07-29-2012, 11:16 PM

Ive run both 1500 and 1600rpm and the 1600rpm worked better.

With both sets of blades.

jones007 · 08-02-2012, 06:01 PM

I fly the 4-bladed head with two matched sets, making sure they are paired opposite each other, and have had no issues. I first used Align CF 425 blades, and have since switched to Edge FBL 473 blades, and both are fine. I even painted the Edge blades, rebalanced them, and it is still fine, but I still have matched pairs rather than a matched set of 4. I fly with headspeed of 1600, 1700 and 1800, and all are good. Haven't tried going as low as 1500.

JoseReyes · 08-02-2012, 06:23 PM

Quote:

Originally Posted by Uglybob

https://www.scaleflying.com/New-Item...s-_p_2439.html

These are the blades I used... they are sold in a set of 4 but are just 2 matched pairs.

I have a set of those and they don't fly well. Other are experiencing the same issue with them.
I since have put the on a drawer to collect dust

I'm back to the scale blades from RCA. You do have to balance them. I went as far as weight matching them, then pair balance them. After that, they just fly awesome.

if you have a digital gauge, measure one of the blade to swash link, make that the master and make sure the others are the same length. it should take care of it... as others have said don't tight the blade grip too hard, they need to be able to self-center on the head.

Uglybob · 08-03-2012, 05:31 AM

The carbon blades flew just as well as the Align FBL blades.. no issues with them so far.

I was going to buy these http://www.scaleflying.com/Scale-Rot...e-_p_1354.html but they have never been in stock.

JoseReyes · 08-03-2012, 08:58 AM

Quote:

Originally Posted by Uglybob

The carbon blades flew just as well as the Align FBL blades.. no issues with them so far.

I was going to buy these http://www.scaleflying.com/Scale-Rot...e-_p_1354.html but they have never been in stock.

This is the only place I know that has them, I have purchase numerous items from them and they are great people. Just email them to find out how much shipping will be to your address. The K 430's are for 500 size

http://www.microhelis.de/afsshop/art...2mkcknaks5ebd3

mojave · 08-05-2012, 01:23 AM

I'm assuming that you're running an FBL unit on this heli. If you are, turn the head gain down. When you slow the HS down and run a multiblade head, the gain needs to be lowered. Also, if you have 2 different weight pairs of blades on a 4 blade head, run the same weight blades opposite of each other (in line with each other) on the head.

07-28-2012, 11:41 PM	#1
Uglybob Registered Users Join Date: Apr 2012 Location: Brisbane, AUS	Test Fly Wobble and Balancing 4 blades? Hi, I did a test flight on my EFL Pro with an Align 4 Bladed head and while the heli flew and wasnt bad to fly.. there was a very noticable wobble where the skids would vibrate from left to right about 20-30mm. The blades are balanced but only with its opposite blade(in pairs).. not the whole set. When I got home I went to balance all 4 but the two pairs are way out of balance. My scales show they weight the same each, 51g, but wont balance on the blade balancer without a huge amount of tape. Would this cause the wobble... i figured having the pairs balanced should be enough.

07-29-2012, 10:21 PM	#7
Christopher J Registered Users Join Date: Mar 2005 Location: Kansas City	Whats the headspeed? Some scalers with multis are "picky" on headspeed. __________________ Christopher J SMI R & D Pilot RCXcel "Size it up, then scale it down"

08-02-2012, 06:01 PM	#9
jones007 Registered Users Join Date: Feb 2007 Location: Monterey, CA	I fly the 4-bladed head with two matched sets, making sure they are paired opposite each other, and have had no issues. I first used Align CF 425 blades, and have since switched to Edge FBL 473 blades, and both are fine. I even painted the Edge blades, rebalanced them, and it is still fine, but I still have matched pairs rather than a matched set of 4. I fly with headspeed of 1600, 1700 and 1800, and all are good. Haven't tried going as low as 1500. __________________ Trex 500 I2RC swash/Radix/BLS153/Quark/DS520/AR7000/ICE50/Neu1706H/1.5Y Trex 600E-Pro QUK/Radix600/BLS255HV/Quark/BLS251/AR7110/ICE280HV/HKIII4035-530 Trex 700LE Align 91H/SB20/Radix710/BLS451(8V)/DS760/BLS251/AR7100R/QUK clutch/tail

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07-29-2012, 12:40 AM	#2
Uglybob Registered Users Thread Starter Join Date: Apr 2012 Location: Brisbane, AUS	I loosened the blades a little since the lower head speed wont be able to move the blades in the grips as easy and while it was helped... it hasnt eliminated the issue.

07-29-2012, 08:57 AM	#3
treotraveler Registered Users Join Date: May 2012 Location: san diego, ca	It's my guess that you used the original efl flybarless pair, and bought another pair? If so, is the other pair flybarless blades also? Are all four blades in track? Are the blades loose enough in the grips to stretch out when spooled up?

07-29-2012, 10:07 AM	#4
Cap231ex Registered Users Join Date: Jul 2010 Location: Indiana , Muncie	It's your tracking it has nothing to do with the blades themselves or your blade grips being to tight or to loose. Check is at mid stick with your motor unplugged with a digital pitch gauge , all blades when measured at the same place usually at the front location should be the same pitch. If done correctly this will stop your wobble issue.

07-29-2012, 09:38 PM	#5
Uglybob Registered Users Thread Starter Join Date: Apr 2012 Location: Brisbane, AUS	First set of blades I tried where scale carbon blades from RCA. They tracked fine and were setup properly. Loosing the grip on those seemed to help too but didnt go away. I then tried 2 sets of the EFL Pro blades from Align... initially the tracking was way out for 1 blade and we went through and res setup the pitch on all the blades and the are all within 0.5deg of each other. In the air the tracking looked fine and once again, loosening the grips seems to help some. My next option is to test the CoG of all the blades and make sure they are correct and rebalance all blades so they are all equal. Going to take a while to do but may be needed.

07-29-2012, 09:39 PM	#6
Uglybob Registered Users Thread Starter Join Date: Apr 2012 Location: Brisbane, AUS	https://www.scaleflying.com/New-Item...s-_p_2439.html These are the blades I used... they are sold in a set of 4 but are just 2 matched pairs.

07-29-2012, 11:16 PM	#8
Uglybob Registered Users Thread Starter Join Date: Apr 2012 Location: Brisbane, AUS	Ive run both 1500 and 1600rpm and the 1600rpm worked better. With both sets of blades.

08-03-2012, 05:31 AM	#11
Uglybob Registered Users Thread Starter Join Date: Apr 2012 Location: Brisbane, AUS	The carbon blades flew just as well as the Align FBL blades.. no issues with them so far. I was going to buy these http://www.scaleflying.com/Scale-Rot...e-_p_1354.html but they have never been in stock.

08-05-2012, 01:23 AM	#13
mojave Registered Users Join Date: Aug 2009 Location: SoCal	I'm assuming that you're running an FBL unit on this heli. If you are, turn the head gain down. When you slow the HS down and run a multiblade head, the gain needs to be lowered. Also, if you have 2 different weight pairs of blades on a 4 blade head, run the same weight blades opposite of each other (in line with each other) on the head.