soarrich

My Feedback: (98)

I've started making my rotor plates for my delta hubs. I was going to use 1/4" aircraft ply, even bought some (Midwest), but it doesn't seem to be of the quality I remember, this made me nervous. I decided to go with 1/8" 6061 T6 aluminum to put my fear of eating a rotor to rest.

I had decided that I was going to use 3 blades per rotor, just because I'm lazy, that's 6 blades rather than 8 so I still get to make a lot of blades. I thought the triangle plate would be harder to cut that the square one of a four blader, but using my miter saw the triangle plates where easy to make.

http://www.netlabs.net/hp/soarrich/rotorplates.JPG

Now I have to make the blade holders....

To be continued.

billf

Hey Rick, great idea! I'm sure that 6061 aluminum will be great.
You probably can drill some lightening holes as well.
A good retired machinist friend of mine has said that a regular band saw can be used to cut aluminum just fine and it does work.

When you are finished, how about posting a photo of your handiwork?

Bill

soarrich

My Feedback: (98)

Yes, I've cut up to 2 1/8" logs of the T6 tree using my miter saw. I've found it's best to use carbide blades. You have to be careful though using wood tools on metal, most wood tools have you handling the stock with your hands, while when you work with metal it's usually held mechanically. I count digitally, so I'm real careful about how I hold the piece.

OK, I plan on showing something new every couple of days. I made the 12 pieces for the blade holders today. I've got to do some clean up on them, then assemble them on to the rotor hub with the "living hinge."

billf

Rick...
I'll be interested to see how you provide for a "downward stop" to keep the blades from hitting the fuse....as well as an "upward stop" to keep the blades from flapping up too high during spin-up.

Bill

floridagyro

Hi,

This sounds like you are building a dual rotor. If it is, you don't need to allow the blades to flex at the rotor hubs. Mount them solid. Only a single rotor autogyro needs to allow the blades to flex or flap.


Phil


Phil

soarrich

My Feedback: (98)

I know that's the normal thing, but the delta hinged rotors seem to spin up quicker. I've also made some solid rotor hubs to see IF there is a differance.

For the downward stop I thought the two lower pieces of the rotor and the blade holder would interfer with each other stopping the downward movement. The upward movement is controlled in the same way, but I have beveled the blade holders inside edge about 15*. I'm hoping that this won't put to much tension on the living hinge, what do you think?

floridagyro

I agree, the delta hub does seem to have the advantage in spinning up quicker. I have not tried them on a dual rotor but I did fix the blades with about 15 degrees of tilt up for a cone shape. I was hoping this would help prevent blade strikes which it did. However, the gyro now wanted to constantly rock from side to side like an old timer airplane with only rudder control on a very windy day. It will be interesting to see if you find the same.

The advantage of a dual rotor gyro, the blades can be built very light and don't require the weighted blades that give stability to a single rotor and being light also allows them to spin up and slow down much faster. With a dual rotor I can do a loop 30 ft above ground and have the rotors almost stop and still have time for the rotors to spin back up. My rotor blades have approximately 15 to 20 degrees negative in 40 % of the blade near the hub and 0 negative in the other 60 %. It comes up to speed real fast and gives a lot of lift.

Good luck,
Phil

billf

Rich...That sounds pretty good. It is pretty much the way I have been doing it. Recently on a small gyro, I used some short pieces of carbon fiber tube attached to the bottom of the hub and extending beyond the hinge so that the flapping part was restricted from flapping down. I also control the upward flap with a beveled edge on the flapping part of the hinge. I think 15 degrees upward is plenty. Some of the other fellows may comment on this too.

Bill

Capt. Crackup

My Feedback: (1)

When running dual rotors, what direction do rhe rotors rotate?

soarrich

My Feedback: (98)

It's my understanding that it'll work either way, but I've only seen them with the advancing blade on the outside.

The guy to ask is Phil in Florida, he's really knowledgeable on twin rotors.

floridagyro

Hi Skip,

With a dual rotor, they can turn either way but for some reason the gyros have more stability with the advancing blade on the inside.

Good luck,

Phil

Capt. Crackup

My Feedback: (1)

Rich, & Phil, Thanks for the response...........I currently fly giant scale aircraft with US Engines. In the recent past I watched a dual rotor gyro fly (demo) at a warbird flyin...It was facinating to see it loop and both rotors actually stopped!!!!!!!!! I am now suffering the ITCH to build a new aircraft...the thought of a gyro has sure got me thinking.....Does any one know of a plan that would be suitable to blow up for a 25 - 35 cc gas engine?? Any help would be appreciated.

soarrich

My Feedback: (98)

Skip

The one I'm building is going to be for a Ryobi 31cc engine. The biggest I've heard of is A of A's Kellett, but I think that's for .90 to 1.20 alcohol engines.

MID-AIR

My Feedback: (10)

HI i am just starting to get into gyros ,going to build a dc gyro from rcm plans or a gyrace , but build bigger after i learn to fly them , i am hooked on ryobi engines,have 3 of them in different aircraft including a flying disk. i would be intrested in geting plans or what ever for a gasser gyro. great site just have to learn to navigate through it AL

soarrich

My Feedback: (98)

Good choices, I've started with my own stuff, not the best way for most guys.


Yea, $50 for a 1/4 scale engine is hard to beat. I've got 3 of them also, only one flying so far.

If you want a Ryobi powered gyro it may be a wait, I don't know of plans yet, and mine is coming along very slowly, these are not just a different type of plane.

boberos

Hi All,
On all my single rotor gyros, I have never used a stop to limit upward blade hinging. The blades will seek their own upper limit based on a combination of lift & centrifigal force. I have had good success & no problems. Of course I build substantial down limits as it is no fun when a blade whacks the fuselage. What am I missing here?

Bob Gardner

billf

Hi Skip...

Rick Anderson has just finished his "Whistler's Grandmother" This is a 200% scale up of John Kelland's Whistler, published in 1991 (or 1992). Judging from the photos on his website it appears he has a pretty good sized gas engine up front. Take a look at:
www.tecwrite.com/anderson.

In all probabability Rick will be flying "Grandma" at the fly-in in September.

Regards,
Bill

Hal deBolt

Hi Skip,
You wish to have a "giant scale" size autogiro, nothing wrong
with that but these things are different from airplanes and proper
arrangements are a real necessity.
Secondly. in a real large size rotor component strength will get
very important, the force that the airstream places on the rotor
is almost unbelieveable.
So it is important that the rotor blades, blade hanger and rotor
head have ample strength, also the attachmrnt to the pylon.
If you would skimp you would surely loose.
You need to scale up a really proven Giro, one that has had all
the mysteries solved.
An excellent subject would be "Giro V" details in the 2/2000 RCM
This one is now flying with a 5 ft. rotor so it is not a toy.
There also is a simplistic rotor head in the 10/2000 RCM that
probably would be sturdy enough
For some time Giros tended to be smallish, recently we have seen examples of "bigger flys better". thus encouragement to go
even larger, tempted to do that
If you get serious and have questions, just ask, should be able
to help.
Good luck,

Hal deBolt [email protected]