Test flew it today and it's shake city. Serious vibration's will rotor balance do this or tail rotor balance?. Also the gyro works for a while and then it spins wildly, Could the tail fin cause the spinning i notice i was twisting, probly cause of the vibrating. I really ain't
to familiar with heli's but it hovered good for about 3 minute's even with the shaking.

It sounds like you've got something loose, (start with the main gear and work your way up), or out of balance.

Have you balanced the main blades? Have you checked the blade tracking?

I'd think the tail rotor being out of balance would give the tail a bounce - which wouldn't fit what you describe.

And the tail fin won't cause the problem either. I've got to wonder about the "twisting", though. The tail fin was twisting? Along the tail boom's axis? Sounds like it needs to be checked and tightened.

I'll have to defer on the gyro question, but it sounds like a part I'd be replacing. Since it works for a while, then stops, it sounds to me like it's goin' bad.

Good luck.

Things to cherck immediately:

1. Ensure that the four 3mm grub screws in the mast stopper are secure and holding the main shaft centered. There is a "witness hole" on the top edge of the upper right main frame section to access these screws; one at a time as you rotate the head.

2. Flybar is secure and centered. Paddles are equi-distant from the flybar yoke.

3. Head/blades are balanced.

Things to look at if all the above is okay:

1. Bent feathering spindles (an endemic Concept problem). These are designed to bend at the slightest distess, in order to preserve the plastic head in the event of a blade strike. They MUST be replaced after even the slightest blade bump while flying/landing

2. Loose gear mesh between main and pinion gears.

There are many other potential problem areas, but the information you provided is limited. There are many different kinds of vibrations, and each one is an indicator of a separate problem/problems.

You have a malfunctioning gyro or tail rotor servo. The tail fins, both horizontal and vertical, have no effect on ANYTHING in the hover, except for this: the Concept has a pusher tail rotor, so while the vertical fin may partially damp the effect of a nose-left command in hover, that is the only effect you will see.

What is feathering Spindle? And also how do you balance the head? I checked the blades and there OK. Changed to carbon fiber prebalanced and it does same thing. Is there suppose to be washers under between the rotor blade and the head? When i changed the baldes theres is 2 washers on both sides of the blade.

Okey-dokey. This must be your first ship, eh?

The Concept has a DDF head which features individual flapping/feathering spindles, as opposed the more common solid through axle. These spindles are what support the blade grip bearings. If you were to remove the eight screws which secure the two halves of the rotor head, you would find that these spindles are held in there by a solid pin with a bushing on each side.

Removing the four additional screws that hold the halves of the blade grips together would reveal the bearing/spacer stack inside, all of which is secured onto the feathering spindle by a 3mm bolt in the outside end.

There a numerous ways to balance a head. Some are better than others, but the ones that work all require some sort of balancer, commonly called a "high-point". DuBro makes the only current one available, as far as I know.

I always check the head with everything except blades. That way I kinow that the flybar and paddles are right. If the head is right, and the blades are right (equal weights and CGs) then the blades will bolt right on without causing any shakes.

Concepts have two different types of blade grips. The early DX/SE/SX grips had 8mm spacing, requiring 8mm roots on the blades. These are now very difficult to come by.

The later SR series of machine had 12mm spacing, which is quite common. The Concept's problem is that it takes rather short blades; 530mm max for the latest iteration.

You said the blades had two washers. That leads me to think you have SR grips that somebody installed the old foamies or after market woodies (8mm root) on. Again, I can't be sure without seeing what you've got.

Steve

These are foam blades, Will the washers cause a balance problem? Would i be better off useing the carbon fiber?

Unless they weigh radically different, the washers won't be a problem.

If you are just starting out, fly the foamies. They do just fine for "normal" flying, and won't tear things up as bad when you dork the ship, since they weigh next to nothing.

In fact, I believe The Empire still carries the foamies. I ordered some last year for a spare set. I fly mine with the foamies in SR grips, with a pair of 2mm spacers on each side.

Oops, meant to get closer. Here ya go...