SMALL - espritmodel.com SMALL - Telemetry SMALL - Radio
Reply
Thread Tools
Old Mar 07, 2011, 11:39 AM
3D and Scale RC Heli Pilot
BlackTitanium's Avatar
Monroe, WA
Joined Jan 2007
836 Posts
Question
HeliArtist 325 Carbon Scale Rotor Blades on a Penta Head?

Has anyone tried these blades, on a 5 blade rotor head, using high head speed (~2200-2350 rpm).

Did you have success or failure with stock belt tail gearing?

Did you have success or failure with 450 Pro Torque Tube gearing?

I am currently testing the TFModel unweighted symmetrical scale blades (29g), on a 450 Pro frame.
Running at 2350 rpm, the tail is just barely holding, it feels like rate mode during forward flight maneuvers.
During hover, it will wind vane when there is wind present.

The HeliArtist scale blades weigh 15g, vs. 29g of the TFModel scale blades.
So, I am thinking that the tail authority will improve with the lighter weight blades?

I have a set of 4, but will have to order a the minimum set of 3 just to have a 5th blade.

The bottom line is, I want stick with using a Torque Tube drive and stock 2 blade tail, so a gear mod is not an option.
BlackTitanium is offline Find More Posts by BlackTitanium
Last edited by BlackTitanium; Mar 07, 2011 at 11:44 AM.
Reply With Quote
Sign up now
to remove ads between posts
Old Mar 07, 2011, 11:46 AM
Redjestird Youser
SidewaysLS4's Avatar
Joined Jan 2009
3,878 Posts
Tail authority wont improve due to the weight, but it may due to airfoil efficiency. IIRC I logged the HA blades at about 1-1.5 amp less current in flight compared to the SM blades at the same headspeed using 4 blades, which should translate to less tail torque needed to keep the heli in place.

I'd hate to say it though, drag vs. tail ratio might still kill the project, probably will need a tail ratio regearing or a quad tail
SidewaysLS4 is offline Find More Posts by SidewaysLS4
Reply With Quote
Old Mar 07, 2011, 12:23 PM
Registered User
Lake Zurich, IL
Joined Jan 2008
5,654 Posts
I'd better stay away from this discussion.
My 5-bladed head using 23*325mm 23g FRP weighted blades (no e-stab) and quad tail cascade. Tail holds at about 2200 rpm.

The interesting point is the tail holds well in pod/boom at lower rpm but not when mounted to MD500.

I don't have a lot of flight time since I last new belt installed. IIRC the tail belt lasted only 40-50 flights but I use cheap belt. May be higher quality belt will last longer.

I have had no problem whatever with quad head on three helis heavy and light blades .... but two of them using 5:1 ratio; and the 3rd on T450 clone with 12t pinion mod and two tail blade.

In fact, I have a quad head with BeastX in pod/boom right next to me ... without tail gear mod and SM no weight blades, not a single issue. The 5th blade changes everything for me.
sidneyw is offline Find More Posts by sidneyw
Site Sponsor
Reply With Quote
Old Mar 07, 2011, 09:37 PM
3D and Scale RC Heli Pilot
BlackTitanium's Avatar
Monroe, WA
Joined Jan 2007
836 Posts
@ SidewaysLS4 - I'm pretty sure that if I put the weighted TFModel scale blades on, that the added weight will induce more counter torque and more current draw.

Anyway, I did a few test flights today, and have achieved better tail authority today, than yesterday.

I did find that my tail rotor blades leading edge, at center stick, were pointing CCW. It was originally set about 8* CW, before I put it into the fuselage.
After correcting the tail rotor, mid stick pitch, the heli no longer drifted CCW or wind vaned while hovering.

Tail authority is now much better, but the tail will still let loose when flying sideways left or backwards. Giving full collective, the tail holds, but does move a little.

If I could find some tail blades that are longer than the Pro blades, I think it would give me more solid tail authority.

I think that I'm going to switch to the Carbon Fiber scale blades, because the
flexible scale blades are causing some control lag and ill affects.

The coning of the flexible scale blades, induces control lag as the blade coning transitions during maneuvers. This appears to causes the e-stab system to sometimes over correct. For example, during a descending forward flight, when I transition to a climbing forward flight, the heli will suddenly jump up a little.
BlackTitanium is offline Find More Posts by BlackTitanium
Reply With Quote
Old Mar 07, 2011, 10:14 PM
Registered User
Singapore
Joined Jan 2004
1,830 Posts
For your tail blades, u can try using Mini-Titan's tail blades instead. It has more surface area than the pro version. U might need to cut off some excess material at the edge of the mounting portion.

SH
Super_Hornet is offline Find More Posts by Super_Hornet
Reply With Quote
Old Mar 07, 2011, 10:18 PM
Registered User
Singapore
Joined Jan 2004
1,830 Posts
BTW... for this:
"The coning of the flexible scale blades, induces control lag as the blade coning transitions during maneuvers. This appears to causes the e-stab system to sometimes over correct. For example, during a descending forward flight, when I transition to a climbing forward flight, the heli will suddenly jump up a little."

Just asking...is your blade to swash plate linkages a straight line or slanted?

SH
Super_Hornet is offline Find More Posts by Super_Hornet
Reply With Quote
Old Mar 07, 2011, 10:20 PM
Redjestird Youser
SidewaysLS4's Avatar
Joined Jan 2009
3,878 Posts
Quote:
Originally Posted by BlackTitanium View Post
@ SidewaysLS4 - I'm pretty sure that if I put the weighted TFModel scale blades on, that the added weight will induce more counter torque and more current draw.
Sidney touched on this a little with a "I'm not opening this can of worms"

But...

Newton's First Law disagrees with this.

I present an Eagletree log of my 450 UH1 running some 49gr cut down T500 blades, some 50gr Smartmodel UH1 Scale blades, and some 25gr 335mm Fiberglass blades.

All logging was done at the same 1650 headspeed. One would think that nearly doubling the rotating weight when comparing the 50gr/ea blades to the 25gr/ea blades would result in an increase in amperage. But the log shows roughly identical amperage draw among the blades tested. Deriving a wattage number from these logs would show a similar pattern reported in the amperage logs, showing that the work done by the drive system would be require the same tail countertorque strength of the tail while running the 25gr blades or the 50gr blades.

Thus, any counter torque requirements needed from the tail will be due to drag of the rotating assembly (increasing at a square of speed), and blade pitch requirements to lift the heli adding to the drag of the main rotor.

The only added power needed related to the heavier rotating assembly would be in starting it in motion. Once up to speed, drag is the variable which affects it.

I hope this clears up some of the often repeated message board confusion regarding this subject
SidewaysLS4 is offline Find More Posts by SidewaysLS4
Reply With Quote
Old Mar 07, 2011, 10:36 PM
3D and Scale RC Heli Pilot
BlackTitanium's Avatar
Monroe, WA
Joined Jan 2007
836 Posts
Quote:
Originally Posted by Super_Hornet View Post
BTW... for this:
"The coning of the flexible scale blades, induces control lag as the blade coning transitions during maneuvers. This appears to causes the e-stab system to sometimes over correct. For example, during a descending forward flight, when I transition to a climbing forward flight, the heli will suddenly jump up a little."

Just asking...is your blade to swash plate linkages a straight line or slanted?

SH
They are straight.
BlackTitanium is offline Find More Posts by BlackTitanium
Reply With Quote
Old Mar 08, 2011, 11:33 PM
3D and Scale RC Heli Pilot
BlackTitanium's Avatar
Monroe, WA
Joined Jan 2007
836 Posts
Quote:
Originally Posted by Super_Hornet View Post
For your tail blades, u can try using Mini-Titan's tail blades instead. It has more surface area than the pro version. U might need to cut off some excess material at the edge of the mounting portion.

SH
I happen to have a set of those, and will give them a try.
No trimming was needed, but I did need to use a shim, in the blade grips.
I had some .015 shims, from my Radix main rotor blades, and trimmed the shims to fit the tail rotor blade grips.
BlackTitanium is offline Find More Posts by BlackTitanium
Reply With Quote
Old Mar 09, 2011, 10:32 PM
3D and Scale RC Heli Pilot
BlackTitanium's Avatar
Monroe, WA
Joined Jan 2007
836 Posts
Tried the Thunder Tiger Mini Titan E325 tail rotor blades today.
They did not improve tail authority. These blades increased the frequency of tail blow outs.

With the swash pitch so low, to minimize tail blow outs, I did not have enough power to counter the wind pushing the heli to the ground.
So.... dirt nap today!

Doesn't look like the 5 blade head and torque tube driven tail is going to work out. So, I guess my little bird will be 500C style, with a quad rotor head and "V" tail.

BlackTitanium is offline Find More Posts by BlackTitanium
Reply With Quote
Old Mar 10, 2011, 12:04 AM
Registered User
Lake Zurich, IL
Joined Jan 2008
5,654 Posts
Sorry to hear the crash.
I still don't know this guy's secret ......

http://www.rcgroups.com/forums/showp...&postcount=120
sidneyw is offline Find More Posts by sidneyw
Site Sponsor
Reply With Quote
Old Mar 10, 2011, 06:48 AM
Registered User
Bad Creation's Avatar
United States, FL, Orlando
Joined Dec 2009
1,067 Posts
Wow and he,s even got a DEAO head that was some nice flying thanks for sharing
Bad Creation is offline Find More Posts by Bad Creation
Reply With Quote
Old Mar 10, 2011, 11:35 AM
3D and Scale RC Heli Pilot
BlackTitanium's Avatar
Monroe, WA
Joined Jan 2007
836 Posts
Quote:
Originally Posted by sidneyw View Post
Sorry to hear the crash.
I still don't know this guy's secret ......
I asked him a few questions:


Did you modify the Tail gear ratio?
No !!
What is your head speed?
1800 (with a slower head speed, your tail rotor is not pleasant
What is you maximum pitch?
I don't know... 9?? I don't like 3D pitch curves
What tail rotor blades do you use?
Std align... (you need a big tail rotor blades)

Heli scale

http://www.dailymotion.com/video/xd9...asse-450_sport
BlackTitanium is offline Find More Posts by BlackTitanium
Reply With Quote
Old Mar 10, 2011, 11:57 AM
Registered User
Lake Zurich, IL
Joined Jan 2008
5,654 Posts
Quote:
Originally Posted by BlackTitanium View Post
I asked him a few questions:


Did you modify the Tail gear ratio?
No !!
What is your head speed?
1800 (with a slower head speed, your tail rotor is not pleasant
What is you maximum pitch?
I don't know... 9?? I don't like 3D pitch curves
What tail rotor blades do you use?
Std align... (you need a big tail rotor blades)

Heli scale

http://www.dailymotion.com/video/xd9...asse-450_sport
When all others fail, he succeeds.
sidneyw is offline Find More Posts by sidneyw
Site Sponsor
Reply With Quote
Old Mar 10, 2011, 06:31 PM
Registered User
Singapore
Joined Jan 2004
1,830 Posts
You should be asking what heli he is using because the tail portion at the frame... do not look like from Align 450 (i maybe wrong but it looks different)

EDIT: Also, ask him to count the tail ratio... that is, spin one revolution on the main rotor by hand and how many turn do the tail rotor turn.

SH
Super_Hornet is offline Find More Posts by Super_Hornet
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Sold Trex 450 4 Blade Main Rotor Head w/ Scale Blades FL62 Aircraft - Electric - Helis (FS/W) 5 Feb 07, 2011 07:19 PM
Mini-Review Heliartist Scale 4 Blade Head review SidewaysLS4 Scale Helicopters 22 Sep 12, 2010 06:49 PM
Discussion New 5 Blades Rotor head from Heliartist ecat Scale Helicopters 6 Jul 27, 2010 03:39 AM
Discussion HeliArtist 325mm Carbon Fiber Scale Rotor Blades fung Scale Helicopters 135 Apr 06, 2010 10:18 AM
Discussion Apache 600 scale rotor head and tail rotor head and main blades kin Scale Helicopters 4 Jan 10, 2010 03:07 PM