3" x 2" mast

[Mike Hook]

Just curious has anyone used a redunant 3" x 2" mast on a gyro? Is there any advantage to using a heavier mast?? (1" x 3" doubled )

Thanks

Mike Hook

[CLS447]

My SxS AC has a 2x2 redundant mast with an extra 1x2 sideways across the back.

This now measures 3x2.

[gyrojake]

Originally Posted by Mike Hook

Just curious has anyone used a redunant 3" x 2" mast on a gyro? Is there any advantage to using a heavier mast?? (1" x 3" doubled )

Thanks

Mike Hook

Mike, it depends on the type of gyro your building. In most cases a stiffer mast makes for more stick shake and frame vibrations.

I built a two seat with 2x3 mast and ended up useing a sliding head to absorb
the shake developed at the head.

I built a heavey single seat with 2x2 mast and was smooth as silk.

Also depends on the type of rotors you are useing.
Dragon wings seem to like a more flxable mast then most rotors.

Also speed has an effect. A slow 45 to 60 mph machine will have less reflex transfer(two rev shake) than a 70 to 90 mph. machine.

R.A.F. used a 2x4 mast but was also built to pivot for and aft to absorb the reflex.

~~JAKE~~

[GyroCFI]

The Snobird tandem uses a 2x3 mast but with a .25 inch thick wall. Super heavy duty.

[GyroDoug]

The Butterfly Super Sky Cycle also uses 3 (1"x2") tubes to create a finished mast that is 2"x3". While that is a very heavy duty mast for a single place the Super Sky Cycle is a heavy single place and because it is also designed to be driven on the road needs to be built heavier than a machine that won't get as much ground pounding. It also uses a Super Slider head and unique control rod end connections to alleviate any shake from the rotor.

[Mike Hook]

Thanks for the replys. I have a project in mind and am sorting out a few things now.

Mike

[Doug Riley]

A really stiff mast defeats one of the mast's necessary functions. The mast MUST be able to flex fore-and aft to accommodate the vibes put out by a 2-bladed rotor. If the mast is rigid, the rotor itself tries to flex in-plane. This can result, and has resulted, in cracking of blades and hubs.

Slider heads and the pivoting RAF mast address this problem in a different way, as does the more elaborate mast suspension used in Bell and Robinson helicopters.

[CLS447]

I've flown Sport Rotors & Dragon wings on my triple mast. Both were as smooth as you could want. Yet the Tandem machines seem to have alot more trouble with that.

(in my experience ).

Also in responce to another subject.........My Sport Rotors needed very little trim spring tension. Maybe even less than the McCutchens on my single place.

[CLS447]

What do you think of THAT ??

[Brent_Brown]

I try not to think much

[CLS447]

Smartass !