Stick shake

[bones]

Ok after looking at and reading many articals and threads about the do's and dont's to stop stick shake, by this i mean many times i have read that the twin masted gyros ie the tandams with 2 masts and plated together just under the rotor head, from what i have read these type of machines are proned to getting stick shake as the mast is not able to flex and give to allow the movements from the blades to be absorbed, and thus always having a stick shake.
Ok now my question, do the tractor type gyro's suffer from the same problem???? cause after looking at some of the pictures and the fusalage weight thread, these machines have a worse design than them from my way of thinking, as they appear to be trianglulated, so there couldnt be any flexing in the mast, however i do not remember anyone talknig about bad stick shake in one of these machines.
Anyone care to comment ??

[ultracruiser41]

Stick shake has alot of other componants than just mast stiffness.

[Fl90]

Hi Bones, I'll take a shot at it. The triangulation on the tractors I've seen is from the side. The mast stifness that gives the shake is front to rear (fore/aft). That's why the slider that some use reduces shake, it is spring centered fore/aft. Sorry I can't be more specific, but it has to do with the teeter hinge.

Also, how's it working out?

[gyromike]

Mark,

On the Little Wing, there are a couple of braces that run up from behind the mast at an angle. The braces are attached to a rubber isolation damper. The mast cant pivot back and forth at it's attachment point near the top of the windshield, and the rubber damper allows enough movement to absorb the 2/rev shakes.

[chuter]

I've got a rubber bushing in each end of my mast support.

I still have a little shake and haven't been able to determine what's causing it. I don't think it's really bad enough to worry too much about.

[bones]

Thanks fellas, i was just trying to get my head around this abit more. I wasnt aware of the rubber mounting how ever i figured something needed to be there help, the best way of finding out is to ask the question,, thanks again.
Barry mast stiffness from what i have read is the main cause of stick shake.