Crazyrcer

How should these be set up to work together? I currently adjust the servos to center using sub trims, then adjust dual rates to give me the right surface movement. It seems like this isn't the correct way to set up a plane though. Is there an online guide or something that can walk me through setting up my planes?

Thanks

TLH101

My Feedback: (90)

I set up my center point first. Then set up end points to match 100% hi rate on my D/R. Then set low rates as a pecentage of hi rates.

Josey Wales

My Feedback: (61)

Thats pretty much how I do it also..I set my ATV's at about 120%..set the neutral by adjusting the linkage, then adjust the dual rates from there..biggest thing is to try not to use a lot of subtrim..

aeajr

My Feedback: (2)

Basic Set-up
by Ed Anderson
aeajr on the forums

Here is my basic set-up procedure, regardless of plane or radio brand. This
assumes a six channel computer radio controlling a full house plane that
has flaps . I will touch on what you can do if
you don't have flaps or landing gear later in the post. If you have more or
less channels the steps will be the same, but the options will be a little
different.

Hitec/Futaba Channel Assignments
JR, Airtronics and others may use different sequence. Doesn't matter

Aileron in 1 - If you have two servos, you use a Y cable
Elevator in 2
Throttle in 3
Rudder in 4
Landing gear in 5
Flaps in 6 - If you have two servos, you use a Y cable

I usually power up the radio and select a new memory position. If I am
replacing an existing profile that I am no longer using, I reset all values
to stock settings of 0 or 100% as called for in each case.

This procedure assumes you have your servos mounted and the control
rods/cables attached to the surfaces and the servo arms off the servos.

Power up the plane. If this is an electric plane, I use a 4 cell receiver
pack battery rather than the motor battery attached to the BEC in the ESC as
I
don't want the motor in play right now.

Check for servo direction. When you work the servo, will the servo move the
surfaces in the proper direction? If not, you use the servo reverse feature
to change their direction. If you are using a standard radio that doesn't
have servo reverse, then you need to remount the servo so the arms move in
the right direction.

To center the surfaces, I hold the surfaces centered with one hand and put
on the servo arms, connected to the rods or cables, so that I have the
surfaces centered as close as possible when I set the arms on. If I have a
screw on/off clevis at the servo end, I will make adjustments so that I can
put the servo arm on and be sitting right at the point where the surface is
centered.

When happy the position, I set the servo arm and put in the servo arm screw.
If necessary I might add some adjustment at the surface end If it has an
adjustable clevis to further center the surfaces. This is especially
important if you don't have the ailerons or the flaps each on its own
channel. I want them 99% right from the mechanicals.

Only when this is done do I do any final centering using the radio. On my
radios, the menu is subtrim that is used to center the servos AFTER you have
done as much mechanical centering as you can. If each aileron or flap is on
their own channel, then I can do more from the radio for the
final fine tuning.

You can adjust max throws using control horn position but I normally do this
from the radio. I use the radio's ATV/EPA to set the max throws on each
channel.

Then I would decide on what I want for dual rates and exponential on each
channel. Typically I use 100% high with 30% expo and 70% low with 30% expo
as my starting points.

Now, if you don't have flaps, and you have your ailerons on separate
channels, 1 & 6 in this example, then you may want to set the flapperon mix
so you can adjust them individually from the radio and set aileron
differential if you like. This also allows you to retask the ailerons as
flapperons for landing.

If you don't have retractable landing gear, some radios will let you put the
second aileron on channel 5, or the second flap servo on channel 5.

Throttle set-up

If this is a glow plane, then you use the same procedure to adjust the servo
that will control the throttle. If this is an electric plane, you should
follow the procedure recommended by the ESC maker.

That would be basic set-up.

Once you get to the field, be sure to a range check before you even think
about flying.
Make sure you have the right model selected on your computer radio.
Confirm all surfaces are moving in the right direction
Confirm there is no binding of any of the control rods, cables or the
surfaces.
Confirm everything is centered.

When you do your first flight ASSUME THERE IS A MISTAKE or that the plane is
out of trim because you are going to have to be prepared to deal with a
problem very quickly.

Once you get it into the air and flying at a good height, then you start to
check the trim and make whatever changes are needed. Remember that a
handling problem may be do to an incorrectly set CG. This might be masked by
adjustments you can make in trim,but that will make the plane fly
inefficiently and may even make it dangerous. So be sure your CG is right as
well.

I hope this has been helpful.

If you are helping a new flyer and plane to teach them to fly, here is the
method I use to teach flying:
http://www.rcgroups.com/forums/showthread.php?t=499281
http://www.wattflyer.com/forums/showthread.php?t=5767

Crazyrcer

In the past I've used just dual rates to adjust the maximum travel. Let me make sure I got this right. I should set my lower dual rate to 70%, then adjust the end point untill the surface is at the recommended maximum surface movement, correct?

RC-Captain

This might not include dual rate settings. My TX does not allow dual rate settings for the throttle.

mstroh3961

My Feedback: (4)

you dont want dual rates on a throttle.....

Ed_Moorman

My Feedback: (1)

Good heavens! Where do you guys get this stuff?

You should not use electronics to set the maximum travel. To do so cuts down on the resolution of your radio on that channel. You should use mechanical adjustments to set the maximum travel by changing the pushrod holes on the servo arm and the control horn. Then set your low rate to whatever percentage you like. I normally guess at 50% for a start, but don't set it at any arbitrary figure and leave it. Fly it and adjust.

If you are setting a lot of travel, use exponential. Remember, the bigger the expo percentage, the wider the soft center will be. If you are trying 3D controls for the first time on ailerons, set 75% expo for a start.

The only time you use subtrim is to center the servo arm when you first start. I think this was in the book length post above. Remove the arm. Turn on radio. Set the arm as close to centered as you can. Now use subtrim the get it exact. Don't mess with subtrim again.

Dual rate throttle?? On some radios you can set different throttle curves which might be construed to be "dual rate throttle" by stretching it a bit. I have been accused at times of having dual rate throttle: on and off.

Most of the radio manuals cover stuff like this. At least my JR ones did, as I recall.

Crazyrcer

Here is what I personally have been doing with my two computer radio flown planes. I center everything and put the control horns on as close to center as possible. Then I adjust them to perfectly center using sub trims, as you suggest. I set everything mechanically to what seems about right (control rods in the center holes etc.) and set all of the dual rates and end points to 100%. Then I check to see if the surfaces will move to the correct maximum deflection suggested for the model. If they are off I adjust the dual rates to set them correctly (un less they are way off, then I adjust them mechanically). What I'm wondering is should I be using the end point adjustment to do this? And how does the EPA effect this sort of thing.

RC-Captain

I would follow the planes recommended settings for low rates before attempting to fly any plane period, rather than winging it at 50% unless you don't have the manual for the plane.

I think you are getting hung up on the precedure rather than what to do first. I can only suggest , that you only use the dual rate percentge when dealing with the low rates. for ailerons, elvator and rudder, and EPA for your high rate settings.

aeajr

My Feedback: (2)

Read my post again:

You have a spec with your model as to what the max throws should be. Using the holes in ther servo arms and the control horn arm you should try to get as close as possible to that setting or to whatever you want to have as the max.

Servo end - innermost hole = least surface movement
Servo end - outermost hole = largest survace movement
Control horn end is opposite
Outermost hole - furtherst from the surface, gives you smallest movement
Innermost hole - closes to the surface, gives you largest movement.

By adjusting servo and surface ends you can come up with the combo that gets you closest to the max throw you want. Sometimes you can get close and sometimes you can't. Get as close as possible.

Get the servo arm on the servo so that hte throw travel is centered. The only exception I have seen is Flaps where the normal rest position is at one end of the travel. So turn on the radio and the plane. With the servo arm off, center all your trims. Now put the servo arm on so that the surface is as close to centered as possible.

These are all your mechanical settings.

Now, and only now, should you start using you radio to adjust things. If you did it right, your adjustments should be small

Then I set subtrim to get them centered

Then I use ATV/EPA to do the final end point adjustments

Now I should have my max throws set.

Now I use DR to set some lower setting I use 70% to start. This will be my mild setting. Wild will be at 100% which would be my maximum throws.

There may be other ways to get the same effect but that would be incorrect use of the controls. On a simple plane it might not matter. On a complex plane it will, so get in the right habbits now. Doing it his way you will have the best use of your servos, their strength and their travel. If you do it all from the radio, it will work but you will not be getting the best service from your servos and you might actually overstress or damage them.

Do what you like. This is what I do.

Of course, RTFM is always the best place to start.

Ernie Misner

Two things.... first >>> If they are off I adjust the dual rates to set them correctly (un less they are way off, then I adjust them mechanically). What I'm wondering is should I be using the end point adjustment to do this? And how does the EPA effect this sort of thing. >>>

I think what is confusing you is that Dual Rates AND EPA (or ATV, auto travel volume, same thing) can inhibit or affect one another. So first, you can simply set the EPA for 120% and be done with it. Then go to the DR and cut back on the percentages to give you what you need. If you are cutting them back a lot though, you will be better off to adjust the holes in the control horns so that your servos are moving through nearly their full range. Otherwise max servo power and precision will not be available.

Second, always the outermost holes in the servo arm AND the control horn arm possible. This will minimize the amount of slop and fee play in the system. For example if using inner holes in both arms, flutter will come on sooner at high speeds because the play in the system is maximized.... not good.

Ernie

laryboy

My Feedback: (2)

the end point adjustment is made after all of the mechanical stuff is done. the end point is set so that the surface goes up the same amount that it goes down (or left and right ) both up and down should be equal and more than what your manual calls high. then set high and low rates as recomended. hard to believe that not one person seems to know what the end point adjustment is used for

Ernie Misner

We know, we know!.... we just forgot to say! Thanks!

Ernie

majortom-RCU

My Feedback: (40)

I know that very few people like my advice on this topic, which is why I keep sticking it in everyone's nose.

The secret to stout, slop-free linkage is to make your own control horns. I have never had a moment of flutter, and I say so boldly, without fear of being knocked down next time I fly.

I design the horns for a length that will give me the maximum throws I want with the servo run out to maximum ATV, which is 60Ëš either side. That is as far as the surface will ever deflect, because the servo will go no further. If I do it right, this setting becomes my high rate, and any lesser deflection is achieved with mid- or low-rate settings. I have on occasion over-estimated, and reduced my high rate using rate settings on the TX.

Another part of the secret is to use ball links on both ends of linkage to all control surfaces. Ball links do not wiggle or jiggle. The only part of the system that has any slop is servo gearlash, which is unavoidable, but kept to a minimum if you set up your high rate throws at maximum ATV, shortest moment arm on your servo connection and longest moment arm on your control horn.

Another possible source of slop is flexing pushrods, if you use 2-56 linkage. I don't mind this size on easy flying 40-60 size sport planes, but anything that is going to be subjected to 3D or aerobatic modes gets 4-40 linkages if its 90 size and up. An exception is pull/pull configurations, where the cables are always in tension to some degree, never in compression from blowback.

My horns are cut from phenolic sheet, two sheets spaced so the ball link goes between them. They are epoxied into the control surface rather than mechanically attached. They are cut and drilled in stacks of four pieces, so left & right are identical twins--crucial for dual elevators.

laryboy

My Feedback: (2)

stop trying to hijack this post

Ernie Misner

Excellent work! What is phenolic sheet and where can we get it?

thanks,

Ernie

majortom-RCU

My Feedback: (40)

I get mine from Aircraft Spruce http://www.aircraftspruce.com/catalo...phenosheet.php
The 1/16" size works fine up to quarter scale, you might go 1/8" thick for 1/3 and up. It's a high pressure baked composite, sorta like fiberglass except the fiber is thin layers of closely woven linen instead of glass, and the resin is phenolic instead of epoxy. Strong, lightweight, saws & drills readily, reasonably priced. Same stuff circuit boards are made of.

Minnreefer

Hello, let me know if I should post this in beginners area, I just got a computer JR radio to switch out my old Futaba on my trainer, should I set up dual rates, there is no mention of setting up dual rates in the manual. Sorry to hijack this thread.

Thanks

Jonathan H