Rotor blade MFGs

[scottessex]

Just to stir up some conversation here since Ron said it is getting boring...
I would like to know the pros and cons of the different rotor blades out there.

I am familiar with Dragon wings and Sportcopter blades, both very fine products.

I had a set of older rotorhawks I used them while I was learning, they were very smooth and almost impossible to flap, they were the old style riveted blades. They flew very well, but no where near the performance of the dragon wings.

I know that the skywheels were good, but no longer produced.

Are the current RotorHawks extruded? or still riveted?

I know that some people like the rotordynes.

Do the rotordynes and rotorhawks come with hub bar and straps?

Any other blades out there worthy of note?

I have seen a set of the Chay-air blades that were most outstanding, but have never flown any.

So how about it, some rotor blade info....what do people like, have tried, some brands better for heavy 2 place, easier to hand start etc.

[All_In]

I could learn a lot here, Great post Scott.
Is there much difference in the price between dragon wings and Sportcopter's blades?

[Fl90]

I got hold of some short chord extrusions and put them on a DW hub.

A lot of prep work just to get the extrusions into shape. Never did get the chord balance down all the way to 25%. Real close on the material thickness where they're bolted (1.75g's will get the rrpm up enough that I'd worry about hole elongation).

On the bright side:
it's something I don't need to try again.
the blades tracked and balanced beautifully.
they spin up EASILY.
they're light.
I wouldn't be too heart broken if these are the first set I prang (asuming my heart still beats afterward)


All my experience is metalwork.......but, I'd like to try to build and fly a set of wood blades, to feel the difference in ride.

Phil

[Racer]

I have heard Jerry Barnett builds a nice set of rotorblades but I have never actually seen them.

[gyromike]

Scott,

I started with Bensen blades on my Bensen. Big surprise huh?
They were smooth but inefficient*. Between the rivets and the air gaps in the upper skins, they ate up power and lost a bunch of speed in hard turns.

I then went to 23' 8" Rotordynes. They were much better than the Bensens. Maybe not as smooth but heavier and lots of inertia.

Nesxt I tried a set of 23' DW's at B-days. I ended up taking them home. :)
More efficient than the Rotordynes, and lighter too @ 42lbs.

I flew with McCutchens once. Not quite as efficient as the DW's (but close)and ~ 15lbs. heavier.

I now have a set of 22' DW's on it. The 23's are for the Dominator I'm working on.

I also machined out some taller Bensen towers so that I can use the top hole in the DW teeter block to get the undersling correct. I'm still making adjustments to get the blades setup to these towers.

*Regarding efficiency, I'm referring to engine RPM vs. cruise speed. Lower RPM = more efficient.

[Friendly]

I flew a set of 24 foot Rotodynes with a 503 on a kb4 (http://www.youtube.com/watch?v=EcBtpeDN_wI&feature=user) I could not believe how easy they start with a little wind. The blades were very smooth but very heavy to be lifting on a tall gyro. The gyro had very good speed and plenty of float on landing. I did not like the feeling of a lot of weight over my head in a tall seated gyro.

I am going to fly that same gyro with 22 foot Dragon Wings and 23 foot rotordynes Saturday. So far I like my DW better. They are light on the stick, they let me fly low and slow and hold their altitude in tight banks without excessive climb when you roll out of a bank as you can see in this video (http://www.youtube.com/watch?v=3N6KKDGnfaY).

I think Mike has a set of towers to help my cone angle as well. I get a lot of shake at 70 but have not fine tune the blades on this gyro.

Bensens would not lift me in real hot weather without taxiing 40 mph.