RunRyder - Throttle curves and mixing

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Century Hawk - Falcon - Raven - Predator > Throttle curves and mixing

rotormonkey
Senior Heliman
Location: Ottawa, ON - Canada

Further to what BladeMaster1 was saying in the other thread...

I'm running my throttle curve at 90-70-90 in idle up. I don't go to 100% because I have 12% throttle mixed in for collective. 90 is as high as I can go without binding the throttle servo when I give full cyclic.
I only have one linkage from servo to motor, and at full throttle it would be pulling further than the arm on the carb would allow. My only concern would be that if it pulls maybe I get lucky and end up popping that linkage off, and my heli is stuck at 100% throttle now.

So, in the interest of higher headspeed, better cyclic, and a cooler heli, should I bump up the throttle curve to 100%? Without the cyclic mixing I find it bogs very easily when rolling, etc.

I dunno.. What kind of mixing do you other folks use? Any? How about throttle curves?

06-17-2008 05:15 AM

Blade_Master1
Key Veteran
Location: Canada

Edited from previous post

even though you use cyclic to throtle mix, Run it at 100% max for your T curves not 90, In real world you won't bind the throtle servo
because you will never do 100% cyclic @ 100% throtle if you could your heli would probably lose control before those #'s match or your probably trying to save your bacon at that point and even then it would only be for a couple of seconds.

If someone else would like to chime in on cyclic to throtle mixes

Maybe old fart would chime in

He also told me to read this
http://www.leisuretech.ca/hints_faster_cyclic.html

JM2C's :)

06-17-2008 05:35 AM

Raffy
Key Veteran
Location: Chicago, Illinois

No stick banging!

06-17-2008 05:41 AM

rotormonkey
Senior Heliman
Location: Ottawa, ON - Canada

I must be missing something here. This is more or less the procedure that I followed. Set the ATVs so there's no binding in either direction with a linear throttle curve (0 - 100). So I get full deflection both ways. Now if I go to high stick, the throttle barrel opens fully, and there's no binding.

Now I add in some cyclic -> throttle mixing, and the servo will bind at full throttle with any cyclic inputs. The ATV isn't a hard cutoff from what I can tell. Once the cyclic mix is added, the servo horn will go further than the ATV is set for without.

Does this make sense? Based on your post, it seems to me that this isn't the behavior you were expect. Maybe the difference is due to radios? I'm on a DX7, maybe Futaba does things differently? Or am I missing something completely?

06-17-2008 01:49 PM

Raffy
Key Veteran
Location: Chicago, Illinois

I use JR radio

06-17-2008 02:40 PM

Blade_Master1
Key Veteran
Location: Canada

Have you read the link from leisure tech ?

On my heli my setup for idle up ( mind you I am using an OS37 on a 30 size Raven)
100 65 45 65 100
cyclic mixes to throttle are 20%

I'm not a pro

but from what I have learned so far you would have to do some serious stick banging to get 100% throttle and 100% cyclic at the same time, besides if your using cyclic mixing you won't need to go to 100% throttle.

Just my 2 cents

Here's a thought bug Ravenhyper50 (the now reformed electric guy)

Here's another thought get a governor for 3D
http://pivotalhobbies.com/sc/produc...35&cat=0&page=2

Best price I found to date

JM2C's :)

06-18-2008 12:14 AM

rotormonkey
Senior Heliman
Location: Ottawa, ON - Canada

Quote
Have you read the link from leisure tech ?

Yep. And here's part of what it says "Be sure that these mixes do not overdrive your throttle servo under any of these conditions.". This seems to contradict your initial advice.

While I agree, full throttle and full cyclic are rare, if I have the curve set to 100% at the high points, and cyclic mixing at all then the throttle servo would be overdriven with *any* cyclic input at all when the throttle is open all the way.

And even if it did only overdrive it when both were on full blast, I still wouldn't be comfortable with it I don't think. Just in case I dork a maneuver, and jam the sticks in a panic.

Quote
Here's a thought bug Ravenhyper50 (the now reformed electric guy)

Actually Ravenhyper50 has mentioned before to me that he never used any cyclic to throttle mixes with his nitro birds. Guess he didn't fly them as hard back then...

Quote
Here's another thought get a governor for 3D

Governers are for the rich and lazy. If it CAN be done without, then I want to learn how. Then if I get rich or lazy, maybe I'll buy the governer. Besides, using a governer will use up the extra channel I need for my water balloon servo.

06-18-2008 02:48 AM

Cambo
Senior Heliman
Location: Phoenix, Arizona

I can't remember how to set it up exactly. If i can find the article i will post a link. I think this might be how to do it.

1. Disconect the servo horn from the servo.

2. Move your throttle stick to the full open position

3. Go into the subtrim for the throttle. Turn this all the way up untill the servo stops. At this point your servo can't physically go any farther.

4. Now with your hand, open the carb to WOT. With the throttle servo still set for full throtle reconect the control horn to the servo. This is now your max point.

If this works the way it should your max throttle point is as far as the servo can go so no matter how much farther your radio tells it to go it will not go any farther.

06-18-2008 03:11 AM

rotormonkey
Senior Heliman
Location: Ottawa, ON - Canada

Okay, that's two people now that have told me that the ATV should be a hard cutoff. I didn't think it was behaving that way, but now I'll go back and double check. Maybe I'm just being an asshat, and this whole dicussion us moot.

I'll have a look tomorrow and keep you posted.

06-18-2008 03:18 AM

Blade_Master1
Key Veteran
Location: Canada

Water Balloon

JM2C's :)

06-18-2008 03:30 AM

oldfart
Elite Veteran
Location: Vancouver, Canada

Some radios have an ATV and an AFR end point setting. The AFR may be the hard end point settings.

06-18-2008 07:24 AM

Blade_Master1
Key Veteran
Location: Canada

THANKS Old Fart

For helping me setup my Raven
I was close in my setup but Thanks to Old Fart it is now perfect

I wasn't comfortable setting up the throttle mixes not knowing what to listen for or look for
Phil took his time and explained how it all works together
showed me a few other neat tricks too.

Having a perfectly set up heli really helps with learning to fly
I finally started doing nose in flying and hovering this was a very very big barrier for me to overcome. Thanks to Phil " fly the canopy"

Thanks to all the people at the fun-fly who made this event happen
it was a very enjoyable and fruitful event.

Wish we had more of these around here .

.

JM2C's :)

08-16-2008 03:05 PM

Furious Predator
Elite Veteran
Location: Kitchener, Ontario, Canada

You can get yourself a governor/limiter dirt cheap here on RR used. the Revmax's seem to go for about $50.

The revmax is what i use on all my heli's. while they can be a bugger to setup, they work great. The revmax is just VERY picky on how you calibrate it. there is a very specific procedure for it.

When i was at the funfly, i had my predator running on a 100% throttle curve. it was the revmax that kept the rpm down. But as you guys saw, the predator/freestyle was running really nice

Shawn
Team Leisure-Tech
Cratering the earth one heli at a time

08-16-2008 04:09 PM

HOMEPAGE

Blade_Master1
Key Veteran
Location: Canada

Not knocking down governors
but since Old Fart got his hands on my heli I don't think I'll need a governor

next summer when I move up to the 50 size I may consider a Governor

What I could realy use is one of those fancy blade tachs like you have. looked pretty cool

.

JM2C's :)

08-16-2008 06:07 PM

rotormonkey
Senior Heliman
Location: Ottawa, ON - Canada

Actually, I got this all squared away. I heard somewhere about the "5 second rule". If you can hold your finger to the engine for 5 seconds it's tuned about right. What they didn't tell me was that you're supposed to gauge it based on the backplate... Not the head

So when I posted this, turns out I was running stinkin' rich. I've since leaned it out. I can leave my finger on the backplate all day and it'd never burn, and it's making TONS of power for my purposes, so I'll even leave it a little rich.

It's all part of the learning process I suppose, but when helihell said... "Uhh.. You're measuring from the backplate right?" - I felt pretty dumb

08-16-2008 07:32 PM

Blade_Master1
Key Veteran
Location: Canada

Could have been worse you could have been checking the pipe

.

JM2C's :)

08-17-2008 03:55 AM

Furious Predator
Elite Veteran
Location: Kitchener, Ontario, Canada

personally, i have always tuned my engines by sound. i have never once checked the back plate temp, by finger or meter. you can't always rely on the amount of smoke, but it can help sometimes.

i know exactly what my YS91 should sound like when its happy, and thats all i ever tune it by...the sound.

im still learning what my YS50 should sound like though.

Yeah, i really like the tach i have. its unfortunate that only 2 of these were made. someone in Hamilton with a lot of brains and too much time made them.

Shawn
Team Leisure-Tech
Cratering the earth one heli at a time

08-17-2008 07:01 AM

HOMEPAGE

the Wasp
rrProfessor
Location: Vt

Shawn,, (although I have tuned many times by touching the back plate) I agree with you, touching the back plate is not the best way to tune,, 15 degrees could make a diff IF you are already tuned for peak power and you don't know it

,, besides that~ my skin could be tougher than the next guy , or not

..

Jim
Buzz Buzz Buzz

08-17-2008 07:37 AM

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Century Hawk - Falcon - Raven - Predator > Throttle curves and mixing

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