Rotor Head Cheek Plates - anyone have the specifications?

[KDOG]

The plans don't give the exact specifications for the reasons that Ralph listed, which is understandable. But I will be using the Black Beauty rotor head with the 23 foot DragonWings with (hopefully) the recoil hand pre rotator. Anyone have the specifics for the plates if they are using the same rotor setup? Thanks in advance...

[gyropilot]

You're getting ahead of yourself.

On custom made gyroplanes like ours, no two cheek plates will be exactly the same. The rotorhead has to be positioned at a specific location fore and aft so the gyro will have the proper static hang angle with you sitting in it and half tank of fuel.

The rotor blades will have no effect on the hang angle, so they're irrelevant.

If you can tell me how much you weigh and the configuration of your Bee, I can take a shot at guessing where the rotorhead will need to be in relation to the centerline of the mast. This will help you make a set of dummy cheek plates out of plywood (or any other reasonably strong material) for an initial hang test. Once you do the initial hang test, for each degree of hang angle you are off from your desired hang angle, move the rotor head fore or aft (as appropriate) by 1". Make dummy cheek plates until you nail the correct location, then build them out of the 1/8" thick 6061-T6XX aluminum.

Information needed for me to guess rotor head location:

Will you be going with the stock Rotax 447 engine?
Wunderlich prerotator?
What type of tail?
Stock tail length?
Stock fuel tank / location?
Instruments?

Regards,

John L.

[KDOG]

:eek: Yikes. My bee will be a bare plans built bee...

I weigh about 145
I will be using the 447
I won't be using the wunderlich prerotator I'm waiting for that recoil prerotator to become available
Will be using StarBee tail, don't know the length
Stock fuel tank location
Starbee instrument pod, all ports with gauges..

[gyropilot]

Because you're so light, I'd start with the *center* of the rotor head mount an inch or so behind (and directly above) the rear wall of the mast and then go from there. It doesn't matter exactly how high you mount the rotor head above the mast either... just give yourself enough room. The length of your cyclic control tubes will be custom made.

My rotor head wound up being considerably aft of the mast because I used the heavier Rotax 503, which has to be mounted farther aft than the 447, and I have a heavy Wunderlich prerotator.

Also, I found it helpful to draw the outline of the cheek plates in a simple CAD program to get the relationship between the mast and the rotor head mount oriented correctly. Then I transferred the paper layout to the aluminum plate and cut out the cheek plates on a foot shear at work. Of course something like a jigsaw would also work to cut the cheek plates along with a file or sander to smooth the edges... but a lot slower.

Good luck,

John L.

[KDOG]

What should the hang angle be? And I guess I do have a long way to go. I'm actually kind of scared about these plates. Thanks for the pic....

[gyropilot]

I believe the correct hang angle is explained in Ralph's GyroBee documentation.

Regards,

John L.

[scottessex]

If you get all the dimensions, I can hack out a set on a hydraulic shear in about 1 minute. What I did was make a set of plates with holes drilled every half inch, fore and aft. You can hang the gyro, use the holes that make it hang correctly, and then mark the holes and make the cheek plates. The cheek plates will be the LAST part you make, so don't even worry about them now.

[Dean_Dolph]

I don't know if this is of interest to anyone or not but GyroTech, the HoneyBee folks, had dummy cheek plates available for their kits. The Mentone PRA Chapter 81? had some for sale at the Convention in '03 but don't know if they still have them or even if the dimensions will work with the GyroBee.

When GyroTech shutdown they placed the HoneyBee plans on the Internet for awhile and they ended up on this web site. http://users2.ev1.net/~gyroman/downloads.htm If you check it out look for the 'Readable Honeybee Plans'.

The attachment is from those plans and shows the dummy cheek plate and an explanation of its use.

[gyropilot]

Attached below are what one of my dummy cheek plates looked like... made from 1/8" aluminum plate.

KDOG, when you get close to the point of needing to mount the rotor head for a hang test, let me know and I'll let you borrow my dummy cheek plates. I have several sets I think that allow the rotor head to be positioned anywhere from directly over the mast to several inches behind.

Regards,

John L.

[KDOG]

SWEET!! Thanks alot guys!!! I'll be in touch when its time!!!