Rudder - Nose Wheel Mix
04-28-2019, 05:07 AM
#1
Thread Starter
Rudder - Nose Wheel Mix
I have a DX8 (Gen 1) and am making my first foray into programming a mix. I am completing a Top Flite Cessna 182 ARF and changed the wire nose gear to a Sierra gear for realism. In addition, I moved the rudder servo to the tail so that the control rod is much shorter to reduce any rudder flutter with a long (30+ inch) control rod. I have two Hitec 645 mg servos installed, so that I can program the nose gear to turn more than the rudder.
So far, I have been successful in mechanically increasing the nose wheel throw to have more movement in the nose as compared to the rudder, but I don't know how to increase the servo throw on the nose gear without doing the same with the rudder. And then there are dual rates that I want to work on the rudder, but ignore the nose wheel.
Here is my current set up:
In Switch Select: MIX is assigned to AUX 1
For MIXING: RUD>AUX1
Rate: 100%
125%
Offset: 100%
Trim: INH
SW: On
Both the rudder and nose wheel move the correct direction, but the adjustments are what are giving me the problem.
1. The nose wheel needs to move more when the Dual Rate is set on the 0 position for the land portion. I am not sure how to get more servo throw without affecting the rudder travel.
2. When I switch to 1 in dual rates, the rudder operates with a little more throw, but the nose wheel servo moves to a maximum end point and will not travel.
3. Same when I go to dual rates for 2.
There is plenty of throw in the nose wheel servo, I just can't figure how to change the programming to make it move more left and right. The rest is still need of total programming for Dual Rates. I don't have to worry too much about the nose wheel moving on Rates 1 and 2 since the gear does not retract, but would like to know how to keep it from moving. Since I land and take off with Dual Rates at 0 the movement for nose wheel is needed, but for Rates 1 and 2, only the rudder needs the increased throw.
I have searched the internet up and down and find plenty of mixing threads, but just not one for the DX8 and for this particular issue. It may be there, just haven't found it.
So far, I have been successful in mechanically increasing the nose wheel throw to have more movement in the nose as compared to the rudder, but I don't know how to increase the servo throw on the nose gear without doing the same with the rudder. And then there are dual rates that I want to work on the rudder, but ignore the nose wheel.
Here is my current set up:
In Switch Select: MIX is assigned to AUX 1
For MIXING: RUD>AUX1
Rate: 100%
125%
Offset: 100%
Trim: INH
SW: On
Both the rudder and nose wheel move the correct direction, but the adjustments are what are giving me the problem.
1. The nose wheel needs to move more when the Dual Rate is set on the 0 position for the land portion. I am not sure how to get more servo throw without affecting the rudder travel.
2. When I switch to 1 in dual rates, the rudder operates with a little more throw, but the nose wheel servo moves to a maximum end point and will not travel.
3. Same when I go to dual rates for 2.
There is plenty of throw in the nose wheel servo, I just can't figure how to change the programming to make it move more left and right. The rest is still need of total programming for Dual Rates. I don't have to worry too much about the nose wheel moving on Rates 1 and 2 since the gear does not retract, but would like to know how to keep it from moving. Since I land and take off with Dual Rates at 0 the movement for nose wheel is needed, but for Rates 1 and 2, only the rudder needs the increased throw.
I have searched the internet up and down and find plenty of mixing threads, but just not one for the DX8 and for this particular issue. It may be there, just haven't found it.
04-28-2019, 06:20 AM
#2
Start with taking the mix out. Go back to the primary screen to “match” up dual ailerons and dual elevators. There should be a rudder to make dual rudders. One rudder is #1 and Nose wheel is #2. Now you have complete control of both servos as independent channels.
04-28-2019, 06:56 AM
#5
Thread Starter
So far I was able to change the rudder type to dual rudders providing a two servo set up. This after removing the mix programming. Now to check it with the plane. Luckily, I am at the beginning of the set up process. Now to check other channels to see if my other set ups remain. The only other programming was the throttle, which is an easy setup.
04-28-2019, 10:25 AM
#7
Thread Starter
Got it working, but had to use a "Y" harness. I think that is what you meant. Now I just need to work in the dual rates to keep the nose wheel from increasing throw when I move rudder to higher rates. Although.being a Cessna 182, how many aerobatic moves will I be doing anyway? I am building it for scale competition. 
04-28-2019, 10:40 AM
#8
No “Y”! If you are using a Y and one channel for the rudder, then the servo matchup with dual rudders was pointless. Because with the Y, you didn’t set up independent servo channels. Did you turn the switches off to the extra rudder channel off? Otherwise it can’t be used. You should have 1-throttle, 2-elevator, 2-ailerons, and 2-rudders for 7 channels total. Are you using Y for independent ailerons and elevator? Typing this out, I forgot about flaps on two channels. So, you need, or would be nice to have 9 channels. Something or all need to be a Y. Put the elevators and/ or the ailerons on a Y. They don’t need adjusted once set up. This way you have independent adjustments for the nose gear steering, which might need adjustments more often.
PS- You could buy a smart-fly for a distribution bus, or match boxes.
PS- You could buy a smart-fly for a distribution bus, or match boxes.
Last edited by RCFlyerDan; 04-28-2019 at 10:43 AM.
04-28-2019, 01:29 PM
#10
Thread Starter
Funny, I was just getting back on to say the Y was not the thing to do. I do have a Y on either the one of the wing functions. Just going from memory, I am pretty sure it's the aelerons because of the recessed flaps on the 182. I may have to reprogram from the beginning. When I shut off the mix, I put a INH on the switch. Which shut down my Aux1..... Not a big deal if I was using the Spektum 8 channel receiver. My bad, I am using a Spektrum 6 channel for bench set up and preliminary testing. If you inhibit Aux1 like I did, there is no Aux2 or 3.....big DUH. 
Once I readjust the Aux1 and make it active, I can assign the rudder to it. Reason for the 6 channel receiver is just so I don't handle or accidentally damage the 8 channel before putting in the plane.
Once I readjust the Aux1 and make it active, I can assign the rudder to it. Reason for the 6 channel receiver is just so I don't handle or accidentally damage the 8 channel before putting in the plane.
Last edited by hookedonrc; 04-29-2019 at 05:22 AM.
04-29-2019, 06:07 AM
#11
I'm going to respectfully disagree with Dan
I use a P-mix for nose steering and use the switch that controls the gear to control the mix, that way nose wheel steering is only enabled with the gear down and centered with it up and not banging around the wheel well when retracted. It also gives you independent expo on the nose wheel.
Just my .02, there's always multiple ways to do things.
I use a P-mix for nose steering and use the switch that controls the gear to control the mix, that way nose wheel steering is only enabled with the gear down and centered with it up and not banging around the wheel well when retracted. It also gives you independent expo on the nose wheel.
Just my .02, there's always multiple ways to do things.
Last edited by BarracudaHockey; 04-29-2019 at 06:10 AM.
04-29-2019, 06:20 AM
#12
I respect that! Thank you! We figured out yesterday that he doesn’t have enough channels for independent servos. He needs 9 channels to have everything independent. He only has 8. I don’t think that it is a C182RG? Just fixed gear C-182, but still could be turned off in the air.
So, yes, if you have a way to accomplish it, I can learn too.
So, yes, if you have a way to accomplish it, I can learn too.
04-29-2019, 07:24 AM
#14
You have to read(skim) a lot everyday. And, as an extra way for extra channels, matching the servos up in the initial set up where elevators and ailerons are matched up, to me is easier than a mix. It sets up an independent channel for the servo. Otherwise, there may not be channels available. On my Lightning, I’ve activated a speed brake channel and used that channel for a gear door.
Always more than one way...........most of the time.
Always more than one way...........most of the time.
Last edited by RCFlyerDan; 04-29-2019 at 07:32 AM.
04-29-2019, 09:12 AM
#15
Thread Starter
I respect that! Thank you! We figured out yesterday that he doesn’t have enough channels for independent servos. He needs 9 channels to have everything independent. He only has 8. I don’t think that it is a C182RG? Just fixed gear C-182, but still could be turned off in the air.
So, yes, if you have a way to accomplish it, I can learn too.
So, yes, if you have a way to accomplish it, I can learn too.
