Sceadu 50 OS 50 Hatori pipe
Using a 401/9253 combo for the tail

Linkages are completely smooth with no catching and no resistance. I am using the stock tail boom mounted servo system and the stock plastic guides with the stock push/pull rod and linkages.

Problem: Tail has a very Notchy feel in hover.

Started with 60% / 60% in AVCS and Normal mode respectively, AVCS mode is now down to 45%. Doesn't waggle like hunting per say but it is hard to describe, the tail does not feel nice like the same combo gives me on my Rappy. I am even using the same NHP Carbon blades on my Rap50 setup but that one feels so much nicer.

I do need to replace the clutch shoe and liner, it is totally hosed but the system does engage well enough to hover. Could this be the culprit? If not, what might be? The whole T/R hub/grips/bearings are brand new and smooth. All shafts are straight, rotors turn very nicely/smoothly. Main and tail rotors tracking nearly perfect. No visible vibrations that are notable.


Any ideas???

Wonder how could you make work that monster pipe with that machine?? I was using the same hatori sb-50 tuned pipe and could never make it work. I had to go back to the one that came with the kit. What do you mean by notchy??? I can tell you that I also have some tail problems on my Sceadu. I´m also using a GY401 gyro with 9253 servo. It is working fine, however the gyro and transmitter sensitivity are working at the max limit possible. Is that the same problem you have??

Sorry the Hatori pipe is a 540 pipe made for the 50

OK got the clutch sorted out

Tail still feels notch and does a the periodic, (not constant) waggle. (waggle waggle, pause, pause, pause, waggle waggle)

No binding anywhere, gain is around 37% AVCS and 55% Normal.

No delay set, limit at 100%

T/R servo seems to be OK, no oddness when tested independantly, the linkage moves smoothly when on the ground and motionless.

Any ideas? I just replaced the entire tail hub/grips/bearings assembly.

Totally at a loss here...

The waggle waggle was from the engine/pipe combo. Pipe was way to close to the header, moved it out to about a 10 mm space, way better. Now I just have to get the gyro sorted.

Well, I had the worst time with this tail ever but I think I finally figured out the issue.

The tail control was still way sloppy and felt like crap. I tried another 401 gyro mounted in several positions, no change. I tried a new 9253 servo, no change

Linkage was smooth and silky I rechecked it, put on the 93mm carbon blades and rebalanced everything, no change.

Checked the belt and pulleys and the belt tension, reset everything. No change

Put a longer and then a shorter servo arm on the servo, no change.

I thought back to a problem I had with my Eco 8 wagging with ANY gyro and setting, nothing changed it and the tail felt like **** in the air but smooth on the ground, similar problem just a long while back.

AHA!!!! I need to check the Sceadu UNDER LOAD to see how smooth the linkage is, my Eco 8 had a prob with bearings binding against a washer but only under load, it was never detectable on the ground.

I pulled the Sceadu tail assembly off the shaft and pulled on both grips (apart and away from the hub center) and turned them to see if they were smooth in movement under "load". I felt a strange grinding on one of the grips. CRAP! I pulled that grip apart and both of the radial bearings (was using two radial bearings instead of one thrust and one radial) fell apart in my hands, balls were flying and metal parts just crumbled out.

Do ya think that was the issue???

Moral: When in doubt check your parts under load as well, sometimes problems only show up when a 'normal' amount of stress is placed on them.

Flew it, last night, that was definetly it. Tail is dead nuts solid.

Now I just have to get the engine running right.

Hi b0gh0s,
Could you actually tune your sceadu engine (O.S.50) with the hatori tuned pipe??

Carlos

I am having a bear of a time with it. I actually took the pipe off and am trying to tune it with a regular 50 muffler. It is still running rough, I think I have prob with the engine itself....

Not sure the engine is the problem. I just put the sb-50 tuned pipe back to my sceadu and will try tu tune it tomorrow. I will come with the relults later at night.
Wish me good luck.

Carlos

good luck and let me know how it goes, I just tried a different engine in mine with a MP1, it has to run a bit hot for my comfort and the headspeed is just astronomical but man does it boogy!

Yesterday I tried to adjust the tuned pipe. First the engine stop running, then it suddenly start to run the opposite way. Could not get the stupid pipe tuned. So I decide to go back to the stock muffler, tune the engine and in the second flight while turning the heli back to me the engine quits and couldn't recover so I end up in a crash. it was a mess.

Very sorry to hear that,
I am going to try the pipe combo one more time and then I am goint to sell/trade it. I don't understand, I have heard several people having very good luck with it, and MHW even had a review of it saying it worked well.

What is MHW? Is this a web site? I would like to read their review.
This night I will look for info. regarding tuned pipes and tuned pipes adjustment. Maybe we are doing something wrong or we are missing something else. Please let me know if you find info regarding tuned pipes.

Good luck to you too,

Carlos

MHW= Model Helicopter World, (its a magazine based out of the UK and widely available in the US. Good rag..

Yeah I have been fussing with these pipes lately and am just about sick of it. I think I am going to go back to mufflers and be done with it.

Well after finding some bad bearings in the tail, and then moving the gyro to the BACK OF THE HELI WHERE THE INSTRUCTIONS RECOMMEND, this machine finally flies like a helicopter!!!

I cheesed the gyro plate since I didn't have the original bolt on plastic one, I used a CF plate that I trimmed to size, and strapped to the heli with zip ties through the bolt holes, and then CA'ed the edges. The plate doesn't move and I can pick up the heli by holding onto it. I just gyro taped the 401 to it.


Reasons:

Even when the machine is balanced and flies well and hovers nicely with no noticeable vibes, there are still vibrations from the engine/start shaft. If I put my finger on different spots on the heli while it is idling, I can tell where vibration is the greatest and least. The lowest vibration point on the whole heli seems to be that spot right above the tail boom mount point on the crutch. Strangely enough, that is where I have the exact same gyro mounted on my R50, and it holds the tail DEAD NUTS in any kind of wind at 40% gain in HH mode. The highest vibration point on the Sceadu seemed to be that very front most mounting plate (the piece that bolts to the heli and holds the battery underneath it). That part shakes like a leaf.

I am pulling the engine this week to check runout with my digital caliper at the fan, the hub, and then the start shaft. I suspect I will find something that is not quite right but I intend to leave the gyro where it is.

Flame away.