collective set up

collective set up

Post by robert h. swietarsk » Sat, 04 Jul 1998 04:00:00



i'm building my first heli(ergo 30), and am ready to set up the
collective. I'm using a jr 622 tx.
with all the linkages in place, is it a matter of just adjusting to
pitch curve on the tx, or do i need to go through all the servo wheel
and spline adjustments as mentioned in ray's book?
bob

 
 
 

collective set up

Post by Beavi » Sat, 04 Jul 1998 04:00:00




Quote:
>i'm building my first heli(ergo 30), and am ready to set up the
>collective. I'm using a jr 622 tx.
>with all the linkages in place, is it a matter of just adjusting to
>pitch curve on the tx, or do i need to go through all the servo wheel
>and spline adjustments as mentioned in ray's book?
>bob

Bob, set your travel adjust (ATV) to 100% both sides of centre and then
use Ray's set-up technique. That way you're using the computer functions
to "fine-tune" your set-up and not to DO the setup which does two
things.

1... It gives you the knowledge of HOW to properly set up a heli and

2... It allows the radio to do what it was designed for, which is
getting the BEST out of the heli with the minimum fuss and work.

If you try to do it all with the Tx buttons, you'll reach the point
where there's no more beeps left, but more beeps needed.

Beep (I mean Beav)

--
Email me (if you want to) at the usual place:

Beavis at nachos dot demon dot co dot uk

You can even visit my web-page at http://www.nachos.demon.co.uk

 
 
 

collective set up

Post by Timothy Morri » Sun, 05 Jul 1998 04:00:00


I have an example of exazctly what Beavis was talking about here. When I
moved from a muffler to a tuned pipe, I needed to reset my throttle/pitch
curves to take advantage of the power. I'm using an FF6 which just has a
simple 3 point pitch curve, plus idle-up. I tried to use a combination of
sub-trim and hover throttle, so that it would hover at around 1500 (which it
had been doing on the muffler), which is in the middle of the range for the
pipe in its stock configuration. I ran out of beeps! I had to turn the servo
arm on the throttle servo 2 splines towards the closed position, *and* use
some sub-trim, to fine tune it, so that it would work properly. The throttle
opening has been slowed so much now, that when the stick and trim are fully
back, the servo arm points to the 3 o'clock position. Seem to use a lot less
fuel now, as well.

--
Tim.
Change .us to .uk if replying by email.

Quote:

>Bob, set your travel adjust (ATV) to 100% both sides of centre and then
>use Ray's set-up technique. That way you're using the computer functions
>to "fine-tune" your set-up and not to DO the setup which does two
>things.

>1... It gives you the knowledge of HOW to properly set up a heli and

>2... It allows the radio to do what it was designed for, which is
>getting the BEST out of the heli with the minimum fuss and work.

>If you try to do it all with the Tx buttons, you'll reach the point
>where there's no more beeps left, but more beeps needed.

>Beep (I mean Beav)

>--
>Email me (if you want to) at the usual place:

>Beavis at nachos dot demon dot co dot uk

>You can even visit my web-page at http://www.nachos.demon.co.uk

 
 
 

collective set up

Post by Pinckne » Sun, 05 Jul 1998 04:00:00


Timothy Morris related:

Quote:
> I had to turn the servo arm on the throttle
> servo 2 splines towards the closed position,
> *and* use some sub-trim, to fine tune it...

Hi Tim.  You may want to redo you throttle setup to eliminate the differential
you've created.  Ideally, the normal throttle curve should be linear from fully
closed to fully open, with hover throttle at about 45% open.  This is
regardless of the engine, fuel, muffler, etc. being used.   Additionally, the
linkage should be at 90 degrees to the throttle arm AND servo arm at hover.
Adjust only the pitch curve to achieve the desired RPM's.  That way, the engine
can "keep up" with the load.  The way I've interpretted your current setup, the
throttle is lagging too far behind the pitch curve, and your engine will bog
under the increasing load as you open it up.

Gp

 
 
 

collective set up

Post by Timothy Morri » Sun, 05 Jul 1998 04:00:00


Greg,

Foirgive me for being stupid, but how do I set the throttle to 45% on a six
channel Futaba, without changing the mechanical set-up?

--
Tim.
Change .us to .uk if replying by email.


Quote:
>Timothy Morris related:
>> I had to turn the servo arm on the throttle
>> servo 2 splines towards the closed position,
>> *and* use some sub-trim, to fine tune it...

>Hi Tim.  You may want to redo you throttle setup to eliminate the
differential
>you've created.  Ideally, the normal throttle curve should be linear from
fully
>closed to fully open, with hover throttle at about 45% open.  This is
>regardless of the engine, fuel, muffler, etc. being used.   Additionally,
the
>linkage should be at 90 degrees to the throttle arm AND servo arm at hover.
>Adjust only the pitch curve to achieve the desired RPM's.  That way, the
engine
>can "keep up" with the load.  The way I've interpretted your current setup,
the
>throttle is lagging too far behind the pitch curve, and your engine will
bog
>under the increasing load as you open it up.

>Gp

 
 
 

collective set up

Post by Timothy Morri » Sun, 05 Jul 1998 04:00:00


Greg,

I have just thought this through again, and what you are doing, by using the
computer (setting the throttle to 45% at half stick) is the same as I am
doing mechanically. I've just re-read Nick Papillon's book, and he says to
do exactly what I've done. I'll paraphrase. Get the RPM right, by adjusting
the hover pitch (mechanically), then if the hover is below mid stick then
the throttle is opening too fast. Correct this by introducing differential.
Move the servo arm one spline in the closed direction, and adjust the length
of the throttle rod. then you have to go back and alter the hover pitch
mechanically, chasing the two back and forth until it is spot on. Small
adjustments can be made using sub-trim. The Futaba FF6/6XH does not have a
facility for setting either the pitch at hover, or the throttle opening at
hover, it HAS to be done mechanically.

--
Tim.
Change .us to .uk if replying by email.


Quote:
>Timothy Morris related:
>> I had to turn the servo arm on the throttle
>> servo 2 splines towards the closed position,
>> *and* use some sub-trim, to fine tune it...

>Hi Tim.  You may want to redo you throttle setup to eliminate the
differential
>you've created.  Ideally, the normal throttle curve should be linear from
fully
>closed to fully open, with hover throttle at about 45% open.  This is
>regardless of the engine, fuel, muffler, etc. being used.   Additionally,
the
>linkage should be at 90 degrees to the throttle arm AND servo arm at hover.
>Adjust only the pitch curve to achieve the desired RPM's.  That way, the
engine
>can "keep up" with the load.  The way I've interpretted your current setup,
the
>throttle is lagging too far behind the pitch curve, and your engine will
bog
>under the increasing load as you open it up.

>Gp