HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Feb 13, 2013, 04:51 PM
Registered User
United States, CA, Modesto
Joined Aug 2012
828 Posts
Quote:
Originally Posted by War Horse View Post
If you guys go with this route, here are the blades you'll want....

http://www.hobbyking.com/hobbyking/s...dProduct=10822
Just got some of the glass blades the other day but they don't seem that flexible.
arrowshooter is offline Find More Posts by arrowshooter
Reply With Quote
Sign up now
to remove ads between posts
Old Feb 13, 2013, 04:59 PM
Registered User
War Horse's Avatar
United States, FL, Hernando
Joined Sep 2012
1,460 Posts
Quote:
Originally Posted by arrowshooter View Post
Just got some of the glass blades the other day but they don't seem that flexible.
OK, these I liked a lot, tho they look funny, they work great

http://www.hobbyking.com/hobbyking/s...e_1_pair_.html

They do need a bit of filing at the root to fit some heads.
War Horse is offline Find More Posts by War Horse
Reply With Quote
Old Feb 14, 2013, 05:26 AM
Brent 黑雁
BThirsk's Avatar
Canada, AB, Ponoka
Joined Jan 2012
1,767 Posts
Quote:
Originally Posted by arrowshooter View Post
Might I ask what difference it would make without a feathering shaft that it would need a plastic blade?
You could goggle that. The blades need to flap a certain amount or the rotor disc can become completely unstable. The bigger the disc, the more the effect happens.
BThirsk is offline Find More Posts by BThirsk
Reply With Quote
Old Feb 14, 2013, 07:22 AM
Goooo!!!! Get to da choppa!!!!
United States, NC, Albemarle
Joined Jan 2013
500 Posts
Quote:
You could goggle that. The blades need to flap a certain amount or the rotor disc can become completely unstable. The bigger the disc, the more the effect happens.
Also on a traditional 2-bladed main rotor, the "see-saw/ teetering" effect of the blades acts like flap hinges from a physics standpoint. On a 4-bladed system, you have to actually place something on it to allow for blade flapping.

Same reason for loose, single pivot blade grips on RC helis. That provides lead/lag movement in the rotor disc. It's not absolutely required on a two-blade system, because leading on one blade is cancelled out by the other. But on a multi-blade system, you have to allow for lead and lag.
kpinnc is offline Find More Posts by kpinnc
Reply With Quote
Old Feb 14, 2013, 08:52 AM
Registered User
United States, CA, Modesto
Joined Aug 2012
828 Posts
Quote:
Originally Posted by BThirsk View Post
You could goggle that. The blades need to flap a certain amount or the rotor disc can become completely unstable. The bigger the disc, the more the effect happens.
Quote:
Originally Posted by kpinnc View Post
Also on a traditional 2-bladed main rotor, the "see-saw/ teetering" effect of the blades acts like flap hinges from a physics standpoint. On a 4-bladed system, you have to actually place something on it to allow for blade flapping.

Same reason for loose, single pivot blade grips on RC helis. That provides lead/lag movement in the rotor disc. It's not absolutely required on a two-blade system, because leading on one blade is cancelled out by the other. But on a multi-blade system, you have to allow for lead and lag.
OK. Looks like I got some research to do before I start this one.
arrowshooter is offline Find More Posts by arrowshooter
Reply With Quote
Old Feb 14, 2013, 09:09 AM
Goooo!!!! Get to da choppa!!!!
United States, NC, Albemarle
Joined Jan 2013
500 Posts
Quote:
OK. Looks like I got some research to do before I start this one.
Not trying to spook you on the project. Most of these things are already engineered into these parts. Just use ALL of them with no "spares" when you build it and you should be fine. Especially true if you just "freeze" the collective actions on the swash to make it FP.
kpinnc is offline Find More Posts by kpinnc
Reply With Quote
Old Feb 14, 2013, 09:12 AM
Cranky old fart
Balr14's Avatar
Germantown, WI.
Joined Oct 2007
21,486 Posts
You may want to think twice before trying a multi-blade head. Cheap ones have rigid head designs that are very unruly. Balancing and tracking blades is a royal pain in the ass. They develop tremendous torque and are not nearly as efficient as two blades. So they require motor and ESC upgrades and very good, metal gear, digital servos. A rigid multi-blade head eats cheap servos like candy. Phasing may be an issue for the receiver, as well. On the plus side, they are extremely stable if you get a good head and flybarless control system.
Balr14 is offline Find More Posts by Balr14
Reply With Quote
Old Feb 14, 2013, 09:50 AM
Registered User
United States, CA, Modesto
Joined Aug 2012
828 Posts
Quote:
Originally Posted by Balr14 View Post
You may want to think twice before trying a multi-blade head. Cheap ones have rigid head designs that are very unruly. Balancing and tracking blades is a royal pain in the ass. They develop tremendous torque and are not nearly as efficient as two blades. So they require motor and ESC upgrades and very good, metal gear, digital servos. A rigid multi-blade head eats cheap servos like candy. Phasing may be an issue for the receiver, as well. On the plus side, they are extremely stable if you get a good head and flybarless control system.
Good to know. My plan was to not spend a bunch of money and just get a 4-bladed rotor and 90 degree swash. I would incorporate it on the 450 with the F45 head and use the Rx/3 axis gyro already there. I figured that I would start with a 4 degree pitch and use a 11 tooth pinion on the 3800kv motor. I am also considering using turnbuckle linkages to make sure that I can get the exact pitch in each blade. I would also have a 4 bladed tail rotor in my back pocket in case I couldn't develop enough speed back there for the 2 bladed tail to work correctly.
arrowshooter is offline Find More Posts by arrowshooter
Reply With Quote
Old Feb 14, 2013, 10:23 AM
Cranky old fart
Balr14's Avatar
Germantown, WI.
Joined Oct 2007
21,486 Posts
I bought at cheap 4 blade head for a 450 clone a few years ago. It looked great and was well machined, but there was no give in the blade holders at all. I never got it to handle right. Pitch changes were very exciting. I had some luck using blades with thin bases and faucet O rings to shim them. But, that caused other problems. I also bought an ESky HBCT heli with a 3 blade head. For a cheap RTF heli, it had a very nice flapping hinge head. A good pilot could fly it without a 3 axis gyro. It still ate cheap servos like candy, though.
Balr14 is offline Find More Posts by Balr14
Reply With Quote
Old Feb 14, 2013, 03:50 PM
Registered User
United States, CA, Modesto
Joined Aug 2012
828 Posts
After further review, and reading on the internet, I will not tackle the 4 blade rotor at this time. Not that it cannot be done, but there are too many variables involved. Think I'll fly what I got for a while and leave that for the way future. Sounded good though.
arrowshooter is offline Find More Posts by arrowshooter
Reply With Quote
Old Feb 14, 2013, 04:08 PM
Goooo!!!! Get to da choppa!!!!
United States, NC, Albemarle
Joined Jan 2013
500 Posts
Quote:
After further review, and reading on the internet, I will not tackle the 4 blade rotor at this time. Not that it cannot be done, but there are too many variables involved. Think I'll fly what I got for a while and leave that for the way future. Sounded good though.
If and when you decide to look into this further, check out the Walkera 4F180. They aren't in production anymore, but the CNC heads are still available. It's smaller than the F45 (I think about a 250-size), but the head design might be worth checking out before trying to convert a 450 head to FP.

I know nothing about these helis, aside from a few Youtube videos I've seen. They seem very stable and VERY fast.
kpinnc is offline Find More Posts by kpinnc
Reply With Quote
Old Feb 14, 2013, 05:49 PM
Registered User
United States, CA, Modesto
Joined Aug 2012
828 Posts
Quote:
Originally Posted by kpinnc View Post
If and when you decide to look into this further, check out the Walkera 4F180. They aren't in production anymore, but the CNC heads are still available. It's smaller than the F45 (I think about a 250-size), but the head design might be worth checking out before trying to convert a 450 head to FP.

I know nothing about these helis, aside from a few Youtube videos I've seen. They seem very stable and VERY fast.
Maybe before I tackle the more-than-two-blades thing, I will consider a fixed pitch 500 project.
arrowshooter is offline Find More Posts by arrowshooter
Reply With Quote
Old Feb 14, 2013, 06:34 PM
Goooo!!!! Get to da choppa!!!!
United States, NC, Albemarle
Joined Jan 2013
500 Posts
Quote:
I will consider a fixed pitch 500 project.
Stepping on my toes! LOL

Blaze away!
kpinnc is offline Find More Posts by kpinnc
Reply With Quote
Old Feb 15, 2013, 04:18 AM
Brent 黑雁
BThirsk's Avatar
Canada, AB, Ponoka
Joined Jan 2012
1,767 Posts
Quote:
Originally Posted by kpinnc View Post
If and when you decide to look into this further, check out the Walkera 4F180. They aren't in production anymore, but the CNC heads are still available. It's smaller than the F45 (I think about a 250-size), but the head design might be worth checking out before trying to convert a 450 head to FP.

I know nothing about these helis, aside from a few Youtube videos I've seen. They seem very stable and VERY fast.
That's the one my buddy has. The only issues are with the tail drive gears and the main gear. They always break if you crash. Since he has stopped that, he has no problems. And it does fly better with 250 plastic blades.
BThirsk is offline Find More Posts by BThirsk
Reply With Quote
Old Feb 15, 2013, 10:41 AM
Registered User
United States, CA, Modesto
Joined Aug 2012
828 Posts
The 4F180 is what got me thinking about the 450 idea, but my stumblers are adapting a 90* swash along with the whole flex head / flex blade thing. I have more reading to do about different style of blades and how they effect flight. I don't want to get involved with having a pile of blades (read $$) that will just sit. It does seem though that the plastic blade that has a long root is what some folks have been using on the CP450's. But there are also ones that use a conventional blade.
arrowshooter is offline Find More Posts by arrowshooter
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Mini-Review WLtoys V912 4-Channel Fixed Pitch Helicopter Mini-Review FyreSG Micro Helis 7667 Yesterday 10:44 PM
Help! MSR Fixed Pitch Question Dubbin1 Micro Helis 3 Jan 11, 2013 08:46 AM
Discussion outdoor four channel fixed pitch heli hereathome Electric Heli Talk 24 Jan 05, 2013 11:15 PM
Discussion BlitzRCWorks Ghost FP RC Fixed Pitch thintz Micro Helis 1 Jan 05, 2013 02:32 PM
Sold 450 Heli tool Lot Align pitch, Swash level, link pliers, more -S- Aircraft - Electric - Helis (FS/W) 1 May 16, 2010 08:07 PM