Linkage setup
 

I need a little advice on linkage setup.

When I setup my 35% radiocraft I used 1-1/4" SWB arms
on all the surfaces and set up triple rates or conditions with
everything on one 3 position switch.

I had low rates for precision flying, mid rates for testing, and
high rates for 3D... it looked more like a fish out of water
flopping around then 3D! ;)

After working hard on my basic routine for my first contest
(then not being able to attend, long story) I find myself
a lot less interested in 3D and really want to focus one precision
flying.

I feel like I have given up some resolution in my radio at low
rate in order to gain the 3D throws at high rate. I want to go back
and setup the linkage again for precision flying.

I am thinking about setting up the linkage so I can get my present
low rates, but make sure the radio dual rates are at least at 100%
for the low rate, and just use the rest 140% for high rates. Does that
sound right?

A few questions:

1) What would you recommend for a high rate setting on each surface
if I am not concerned about 3D flying?

2) What about low rate settings?

3) I don't like flipping switches during a routine so is it best to set up the
plane so it will snap and spin well and use that as the lowest rate, or
do you use a higher rate for snaps and spins and flip switches?

4) Should I have more down elevator then up ? if yes why?

The plane is a 35% radiocraft Extra with a DA 100. Radio is a Futaba
9C Super.

Thank you for the help.

BTW everything is set up with a Hitec programmer.

RE: Linkage setup
 

Kelly,

Great question.
You are absolutely correct in your thinking. 140 ATV / 100% DR's for precision.

My throws are basically this. (Carden 40% 260)
Aileron: 23.5 degrees up and down
Elevator: 12 up and 13.5 down.
Rudder: 30 low (Snaps) 45 high (Hammerheads and rollers)

If you have set up a rudder to elev and aileron mix, your probably are using up elevator for each side of rudder throw.
Once you have that set, leave those mixes on all the time. Its not a Knife Edge mix like people call it. Its a Rudder mix. Meaning, you need it anytime you use the rudder.
The reason you need more down elev throw than up is becuase when you do a negative snap, your getting up elevator (From the mix) and you need down. The extra degree and half makes up the difference for the mix.

I fly JR and use flight modes. Heres how I have them set up because I dont like flipping switches either.
With this set up, I only have to flip into FM-3 once or twice during a sequence.

FM-0
IMAC rates and low idle for landing

FM-1
IMAC rates and high idle for flying. (ever lose the motor in a spin during a contest??)
I also have a throttle to elev mix in this mode.
A touch of down elevator with idle for straight downlines.

FM-2
3D throws and low idle. (I like flipping to high rates on landing rollout but dont want the idle coming back up)

FM-3
IMAC rates with a higher rudder throw for Hammerheads and Rollers

FM-4
Not used but, same as FM-3 in case the switch gets into that position by mistake.


Hope that helps.

RE: Linkage setup
 

Hey Kelly- Wayne gives good advice. He's a friend of mine and has flown at our field. I just have to get him back out there. Great flyer.

Wayne- Kelly is one of my flying buds- we just about got him out to the last contest but I am sure we'll get him out there at a contest before too long.


Since the beginning of the season I have taken the 3D rates out of all of my 40% planes- they are now set up only for IMAC. You're right on with the 140% and reducing the throws mechanically. Increases torque and resolution too.

Personally, I don't like flipping the switches around. I have conditions set up so I only have to worry about a single switch. I fly most all of my sequence on the first condition. I have another condition set up for hammers and rollers that is the same as the first cndition except for high rate rudder. That's it for me.

I have been burned a couple of times when I didn't have the right condition set up. Here's a couple of examples:

- I used to set up a condition for rollers that had very low aileron throws. After a roller, I didn't switch back and the snap in the next manuever barreled and I got a zero. So- I don't mess with the aileron throws anymore.
- At the first contest this year I still had 3D rates. Not liking lots of conditions, I had a "sequence" condition and a "3D" condition. I used the 3D condition for hammers. I went into a hammer- 1 1/2 negative snaps up, flip to condion 2 (3D) hammer with belly in, snap and half roll out. Only thing is I hammered right through the sun- lost some composure on the way down and didn't switch out of 3D rate. Spent the rest of the sequence wondering why my snaps sucked.


Dave

RE: Linkage setup
 

Very true.
We have all been there.

The key to consistent flying for me, is keeping stuff simple.
Find what works for you and stick with it.

I travel to most of the contests with one friend of mine. He has his radio set up just like mine.
We can switch planes and its not an issue.

RE: Linkage setup
 

Thanks for the help guys...

Trying to keep it simple works for me! I do have one switch for idle
up and idle down. The only other switch I have set up is the rate
switch.

I will work on the linkage to try and increase my low rate Duel rate
numbers. I looked agin after I posted and as an example my low
rate elevator is at 50%. I do 96% of my flying on low rate so I
guess I am wasting half of my 1024 resolution?

I wonder how I will feel the difference in the controls?
Will be able to lower my Expo with higher resolution?

Thanks again.

RE: Linkage setup
 

You'll just have to go out and fly and experiment. Only you can determine what is most comfortable and what setup performs best for you.

I recently switched out my transmitter springs to very stiff springs. As a result, I have reduced the expo on my ailerons down to 22%. I think I may go down a bit more. I'll be experimenting with the elevator and rudder too. Fly, fly, fly, change expo, fly, fly, fly....


Dave

RE: Linkage setup
 

Just talked with Kurt about this on the phone. His planes
are set up pretty much like mine, with 3d and percision rates.

I am charging up the programmer now and will work on
the plane tonight.

RE: Linkage setup
 

I think the Hitec programmer is confusing the situation
on my end...

Elevator setup...

I have moved the linkage on my SWB 1-1/4" arm to the
closest hole to the center - .8" out. My pivot point on the
elevator horn is 1.75" out from the hing line.

ATV at 140
Max servo rotaion around 75 to 80 degree's when programmed.
High rate at 140% = 25 degree of throw.
Low rate at around 60% = 15 degree of throw with about 40
degree's of servo rotation.

The low rate % is only 10% hight then I started, while the
high rate throw has bee reduced by 20 degrees?

It seems like since the Hitec programer is alowing the servo to
rotate more then 60 degree's I am having to reduce the D/R
more to lower the throw since the servo arm is moving the
surface less at or near the end points.

How do I work this out? Is the programmer actually increasing
resolution since the servo is able to rotate more?

RE: Linkage setup
 

Are the rates below for aileron and elevator your
maximum available rate? or do you get a little more
if you crank your DR's up to 140?

Do you know how many degrees your servo's are rotating
at those throws?

RE: Linkage setup
 

JR DR's do not go above 100%.
The travel adjustemt (ATV) for all servos though is 140.
MY IMAC rates are the lowest my surfaces move. I dont need the surfaces any slower than that.

I have never used a Programer so I cant help you there.

RE: Linkage setup
 

Wayne,

Do you use the same amount of aileron on vertical snaps ? I've gone to two flight modes for snaps because I like more aileron on vertical snaps but find the same amount of aileron to be too much for horizontal and 45's.

Thanks
Albert

RE: Linkage setup
 

Albert.

Same rate on all snaps for me.

RE: Linkage setup
 

Hurt my back the other day, but I got a little more time
to play with the linkage....

I have gone all the way out on the controll horn, 2" from
the hinge line to pivot point and all the way in on the servo arm
.8". On low rate I am still below 100%, 75% is the best I can do,
and now my pushrod arm is not 90 degrees to the controll
horn.

I drilled the hole for the controll horn screw with the idea that I
would use 1.25" servo arms. In hind site I should have mounted
the servos in the stabs like the aileron servo's ar mounted on the
Composit arf planes.

Looks like I will have to reduce the servo arm to 1/2" or 5/8"
to get ATV at 140 and Dual rate to 100% on my low rates.

Does that sound right to you guys? What length servo arms and
controll horns are you guys using?