Stick shake

Insert shim along either side of the joint between the teeter block and hub bar, fore and aft on either side along the side of the teeter tower. Pick a side, it will either get better or wrose, move to the other side if you make it worse. I would go in increments of .002 at a time.

Bobby
View attachment 1152799
Thank you, Bobby. I could not think of any other place else, but I like to ask to be sure.
The other thing, which intrigues me (hope he can see this) how Dennis from GyroTechnic achieved, according to Ron A., so smooth gyro flight without a slider (I believe) and round mast. Where 2-revs go? I contribute amazingly smooth Wolfi's gyro to his round mast ( Chuck B. talked about the advantages of the round mast for years) and wonder why so many gyro pilots ( especially in the US ) suffering from stick shakes, but never use round masts?
 
Bensen began with round tube airframes but switched over to square tube airframes to ease things for homebulders whose only tools were an eggbeater drill, a hacksaw and a file. By locating bolt holes tangent to sidewalls, the worst place structurally, internal spacers or nutplates could be eliminated and a very simple drill jig could be fabricated from a short piece of angle iron.
The manufacture of hobbycopters is still a limited scale business with limited design resources.
 
Thank you, Bobby. I could not think of any other place else, but I like to ask to be sure.
The other thing, which intrigues me (hope he can see this) how Dennis from GyroTechnic achieved, according to Ron A., so smooth gyro flight without a slider (I believe) and round mast. Where 2-revs go? I contribute amazingly smooth Wolfi's gyro to his round mast ( Chuck B. talked about the advantages of the round mast for years) and wonder why so many gyro pilots ( especially in the US ) suffering from stick shakes, but never use round masts?
One mans "smooth" is another mans "rough" and vice versa.
Some people have different levels of acceptability.
My gyro with it's round mast is the smoothest gyro I have been in by a long long way.

wolfy
 
Here's a photo to add to Bobby's drawing.

1624959637093.png

I agree with Wolfy, subjective opinions about vibration are very subjective.
 
The shim in the picture above results in tracking adjustment.
...Dennis from GyroTechnic achieved, according to Ron A., so smooth gyro flight without a slider...
Denis has tacking adjustment built into his hub bar and teeter block. No shims required.

You can see a picture of it on the Razor Blade section of his website.

razor-blades

Each manufacturer does it slightly differently but there are the basics of balancing, stringing, and tracking to follow to get the blades as smooth as possible. Sport Copter blades are a good example.

 
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One mans "smooth" is another mans "rough" and vice versa.
Some people have different levels of acceptability.
My gyro with it's round mast is the smoothest gyro I have been in by a long long way.

wolfy
Agree, but having flown in the Gyro before we replaced the rotor blades I had a baseline feel for the abnormal vibration.
 
Two videos of hands off flight I remember as being notable by their absence of stick movement. One was by Scandtours/Girogos on the Aviomania, the other was Denis on a Razor Blade test flight.

There have been a number of other hands off demonstrations I have seen but these were from videos from the ground and so stick movement much harder to see.

This was an earlier thread on the subject and contains good information on the subject. This also contains the video I referred to with Giorgos in the Aviomania.

 
(hope he can see this) how Dennis from GyroTechnic achieved, according to Ron A., so smooth gyro flight without a slider (I believe) and round mast. Where 2-revs go?
My schedule does not allow me to be on the forum too often, but I do try log on every couple days to see if anything needs my attention.

"Glass smooth" is certainly a relative term. (But it can be considered fitting when compared to some machines out there)

VIbration in a gyro is the nature of the beast.

Through development of Razor Blades, we have spent EXTENSIVE time and money on the precision of every component within.
Our assembly and curing process assures maximum repeatability in every blade produced.
Precision balancing, and then tracking on our test stand before the baldes ever get mounted on an aircraft removes almost all variables.
Dynamic balancing as per Mike G's systems....Even better.

So, "Absolutely no stick shake"?? No, not a fair statement. "Absolute minimal stick shake" You bet!

Denis
 
Bensen began with round tube airframes but switched over to square tube airframes to ease things for homebulders whose only tools were an eggbeater drill, a hacksaw and a file. By locating bolt holes tangent to sidewalls, the worst place structurally, internal spacers or nutplates could be eliminated and a very simple drill jig could be fabricated from a short piece of angle iron.
The manufacture of hobbycopters is still a limited scale business with limited design resources.
"only tools were an eggbeater drill". Chuck, so, we can (loosely and in general) call those shaking gyros "eggbeaters" too:)
 
Georgi, I can still picture my grandmother using a hand cranked eggbeater to beat eggwhites to make meringue for pie topping.
I doubt if hand cranked eggbeaters are still being made. (just those with rotor blades)
 
I knew I'd posted something about stick shake before, I finally found it.
https://www.rotaryforum.com/threads/stick-shake-and-control-friction.1122020/

Resasi, I'm nit picking but sometimes it's important to be precise.
You say:
Georgi said:
...Dennis from GyroTechnic achieved, according to Ron A., so smooth gyro flight without a slider...
Denis has tacking adjustment built into his hub bar and teeter block. No shims required.

The slider is there primarily to reduce 2/rev vibration transmission, tracking causes a 1/rev vibration so there is little or no relationship between the slider and tracking. A slider might do something to reduce a 1/rev vibration in the cockpit, due to a tracking error, I don't know, but the real solution for a tracking error is to change the pitch of one or both of the blades (as done by shimming or Dennis's and Jim's "half moon" or Magni's eccentric). The slider (when it works) only reduces the transmission of vibration from the rotor to the cockpit/frame/chassis it doesn't reduce the vibration at its source. Properly done, tracking reduces the vibration at its source.
Sorry to be so pedantic but vibration is a subject that is talked about by many but understood by so few.

Mike G
 
Mike I am a complete neophyte and quite happy to bow to your superior knowledge in this field, and it is certainly not nit picking by any means.

We all endeavour to help...as best we can. In my case not much in certain fields, better in others.

I am pretty sure you are in a field you are undoubtedly way more advanced than I.
 
Just chiming in to say I've learned a lot about this topic from this discussion thread. There are some adjustment features of my GyroTech teeter block that I didn't fully understand until this conversation. The diagrams and explanations here have been educational.
 
Brian, do you have the old teeter block that rides on a (part) cylinder?
I wanted it, but was told, they now do it the same way as Auto-Gyro
(it's more precise to use thin shims - but probably also cheaper to make)

Cheers
Erik
 
Brian, do you have the old teeter block that rides on a (part) cylinder?
I wanted it, but was told, they now do it the same way as Auto-Gyro
(it's more precise to use thin shims - but probably also cheaper to make)

Cheers
Erik
Good question and I will have to check. I bought a new teeter block from them (with bearings instead of bushings) when I purchased the rotor head but I have not test-fit or replaced it yet. Now that I recall a mental picture of it I don't believe it has the cylindrical faces like the old one does. I'm glad you asked this question because it didn't dawn on me until now.
 
Georgi, I can still picture my grandmother using a hand cranked eggbeater to beat eggwhites to make meringue for pie topping.
I doubt if hand cranked eggbeaters are still being made. (just those with rotor blades)
$17 at Amazon.



The drills can still be had, too.

 
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