I'm still real new to the heli world , But I have flown Planks and drivin RC cars.
These helis are just plain tough to get tuned.
I have just had to forget what I know about engines on this thing.

I got it to Idle good.
If I lean it out anymore to get the transition better. It sounds bad at idle.
I have it set up now where is fires up well. the transition is ok as long as I don't just try to punch it from Idle. You know try to get them blades up to speed real fast. It really falls on it's face when you do that. The leaner I get the bottom end the better the transition seems to get.
As far as mid range. It seems good
I have to keep the throttle curve down to lower the head speed, but at the same time I need it up Higher for performance.
Now at the top end it seems to bog or it just has no lift.
Too many things to adjust. And I'm blowing Glow plugs about every 5 or 6 tanks

How do you know when your engine is right and it's time to focus on Pitch and throttle curves?

Sceadu with an OS 32 and stock woodies
Tom

The OS manuals have a good section on engine adjustment. Eg on the os website or on my website www.cg.its.tudelft.nl/~wouter. The only thing that lacks it that you have to adjust pitch and throttle such that hover is at the right rpm (1600 or so, depending on your heli).

Yea I have the manual
Actually I downloaded it from the site.

Something else interesting I found on there
the Hp at RPM for the 32 and the 50

They both peak at 17000 RPMs
The Sceadu 30 has a 9.66 to 1 ratio gearing and
the Sceadu 50 has an 8.7 to 1 ratio

From what I understand the head speed should be around 1700 to 1800?

If this is the case the 30 would be workin right in its range , with a head speed of 1759 at peak hp

The 50 size would be smokin the rotors at 1954 rpms at peak Hp

Now you wind them up to there max 20000 rpms , I see things startin sling off.

I just wish I could figure out when to leave the motor alone and start workin on the pitch curves

Tom

Tom,

The .50 uses the torque of the motor for power instead of the hp. I tried running the higher gears with a .50 to get the hp and I would over speed the head all the time because there was not a big enough load.

Sounds like the top end is too lean.

Open the main needle, reset idle and try again. I say lean because you are blowing plugs.

Does it acutally hover? You say mid-range is OK, but also say it has no lift at the top end. Mid-range is usually defined as hovering power in helicopters, top end is for max. pitch climbouts.

Yea
I wind it up to half stick.
Purrs like a kitten.
Slap it up to 3/4 stick and it leaps off the ground.
that part is ok
then If I go full stick , its like theres nothing left.
it just start to rise slowly and the engine sounds like its really loading down.
I think this is one of those things you just have to see and hear to answer.
Right?
too Lean huh
This aint the first time I blew a plug in flight either.
I know I have done it now when I land, because the idle will be rather high after flying around a bit.
then I try to lower it on the transmitter and it will die.
And sure enough , each time the glow plug was shot.
If I richen up the top end it doesn't want to lift off from 1/2 stick
Should I richin up the top and lean out the bottom?

Sounds like it might be worth while for you to start over from the beginning...if you fiddle with different things long enough, it's possible that one or more are off to the point that it's just not going to work. I have the same heli and engine as you and it runs great, so here's my step by step.

1. My hovering pitch curve is set up so that I'm hovering at about 5.5 degrees of pitch at half throttle and just below 3/4 stick. Confirm that this is what you've got too. (My head speed ends up just below 1800 in the hover, which is high for hovering, but I like it and we can deal with fine tuning your headspeed later.) Set high stick for 9 degrees. Make both your pitch and your throttle curves linear from hovering to max.

2. Reset the low end needle to the factory setting per the manual. Open the main needle 2 turns.

3. New OS #8 glowplug.

4. Fire it up with the throttle trim at full, let it run for a while and slowly advance the stick to get a hover (if it's too rich to get a hover, then lean it 1/4 turn). Note the stick position. If you are not getting a hover at the stick position that produces 5 to 5.5 degrees of pitch, then increase your throttle curve at that stick position until you are getting a hover. If it's lifting off before 5 to 5.5 degrees, then reduce your throttle curve at that point.

5. AFTER hovering for a few minutes, note how much smoke you are getting and set her down.

6. Bring the throttle trim down to 3/4. It should be idling without the clutch engaged. There is simply no reason to try to get it to idle at a lower trim setting than that. You may be trying to tune the carb for a really low idle (say 1/2 or 1/4 trim) and that could be your problem right there. Now rev the throttle a bit from low stick to 1/2 stick. If the response is okay and you have a solid smoke trail (which will vary based on brand of fuel, nitro content, etc.--I'm running CoolPower 30%, so I'm looking for a really solid smoke trail. If you're running Wildcat 15%, then just make sure you're seeing smoke). If the response is lacking, but you've got plenty of smoke in the hover, try leaning the main needle 1/8 turn at a time, and bring it into a hover after each adjustment to make sure you are still getting a nice rich run. If you reach the point where you think further leaning of the main needle is not advisable, but your throttle response is still lacking, then lean the low needle 1/8 turn at a time and retest response (you might want to open the main needle a touch if you find it necessary to lean the low needle--I've never had to touch the low needle).

7. Once you've got decent throttle response and good mixture in the hover, advance the throttle smoothly (but with authority) to max and watch it climb out. Your head speed should stay about the same and the smoke trail should be consistent. If it's going lean on you, open up the main needle just a touch and try again until you have it right. Vice versa. If the rotor bogs, land it and reduce the high point of your pitch curve a bit at a time until you find that your headspeed stays constant. When doing this MAKE SURE TO KEEP THE PITCH CURVE LINEAR ABOVE THE HOVER POSITION. Ideally, you should inhibit the points in between hover and max, but if this doesn't work out, then just adjust the intermediate points to keep it looking linear.

Hope this helps and that I'm not just telling you stuff you already know.

Hey Adam
It is Adam Right?

Thanks a bunch
I'm printing this out as I type.
I will take it with me the next time I get to fire her up.
Its suppose to storm tomorrow
At least I hope it does
we really need the rain

Anyhow
I might have found one little problem to add to the mix while I was flying yesterday.
I have been havin trouble getting the muffler to stay on.
This muffler (brand unknown, but not stock) has a hole in the top and the bottom. I'm guessing this is so you can put the pressure line on either side depending on which side of the heli the muffler is mounted on.
When I got this heli (used) it was not plugged so I plugged it.
Well the screw fell out. So i'm guessing thats when it started going lean on me.
When I first started I had the throttle Linear from 0 to 100
It ran real good there , but the head speed seemed quite high.
But it didn't flutter the blades.
I started lowering the throttle curve and things just weren't the same after that.

I haven't been using the OS #8 plugs
I have been using some Thunderbolt R/C Long Glow Plugs with the idle bar. it's what I use in my 1/8 scale RC buggy
I will do like you wrote and start over again.
Who woulda thunk these helis would be so much work.
But they are fun.
Thanks again
Tom

Yes, it's Adam. And you are most welcome.

I wouldn't worry about the throttle curve being linear below the hover point. Just make sure the throttle comes in so the rotor speed gets progressively faster until you reach liftoff. Avoid a throttle curve that causes the rotor to overspeed before lift off, and then slow down again as you approach hover pitch--that means you're bringing the throttle up too fast below the hover point.

I use idle bar plugs sometimes in my planks too, but the OS #8 is really great for this engine. Enya #3 works well also.

Don't forget to spend some time on the bench with your pitch guage to make sure you know where the stick is at 5-5.5 degrees of pitch. Also, you need to take the engine out to reset the low end needle...it's the only way to do it properly because you need to sight down the barrel of the carb to find the correct position of the needle.

Best of luck

Hey Adam
I did like you said.
In the yard it all seems good now.
I will take it to the field tomorrow.
Rather than removin the engine to set the low end . I just yanked the carb off of it.
Alot easier.
Thanks for your help
The 5.5 degrees of pitch you mention at 1/2 stick?
juts below 3/4 stick
THats a little confusing. Do I want the 5.5 to come in between half and 3/4 stick? That what I ended up doing.
My engine doesn't smoke as much as some I seen.
I'm runnin Powermaster 15% heli.
Tom

15% will smoke less than 30% and cool power smokes more than powermaster...so I wouldn't worry about it. 5.5 degrees somewhere between 1/2 and 3/4 stick sounds about right. It's arbitrary really, and comes donw to how linear you like your curve and how much high and low pitch you have. If it ain't broke--don't fix it.