bikerbc

I am installing a 8 channel reciever in a Hanger 9 PA18 . I am using a DX8 transmitter . The problem I have run into is I don't have enough room for everything . I have 4 servos in the wings . 2 for flaps and 2 for ailerons . I also have two elevator servos , one for the throttle and one for the rudder . That makes eight . I still have my ignition to hook up and it would be nice too hook up my lights . I was wondering if I could Y my elevator servos to free up one channle for my ignition and then possibly Y my ignition and hook my lights up there . That way my lights should come on and off with my ignition . Does this sound possible ? I am not too swift with electrics .

52larry52

My Feedback: (1)

Yes to using a Y harness for both items. Depending on the mechanical set up of the dual elevator servos, you might need a reversing type Y harness for the elevators. Some don't like a reversing Y harness but I have used them without problems. Did this plane come from Hanger 9 designed for dual elevators? If so, then they should say something in the instructions about the hook up required. Remember, "when all else fails...read the instructions" ! Have a good one biker.

Steve Percifield

My Feedback: (14)

you could actually Wye, the elevators servos, the aileron servos, and the flap servos, if you wanted. Just be sure you have enough battery capacity for all the servos. You could also one of the power box thing which provides multiple outlets for each function. Like Larry said, some folks don't like wye's and reversers, but I have used both for years and had no problems'

JohnBuckner

My Feedback: (1)

Good morning Ken and Larry. Yes Y cording of the elevator halves can work and have done if on some rare occasions. There is an alternative if this airplane has normal forward servo location instead of back near the stabilizer and you are willing to use a single elevator servo. In addition its not all that difficult to do.

It involves using full length pushrods as normal with either one set up 4-40 or 2-56 rod ends whichever you choose and one attached to the servo output arm using whatever methed you choose. This rod is left a little longer than normal before it slides into the carbon fibre rod. (I use almost exclusively CF rod 2-56 or 4-40 from Derrol Cady).

The second rod is sligjhtly bent as is the first rod near the servo and the two rods run parallel for several inchs and its here that appropriately sized wheel collors are placed and the two serve to lock the two rods together as well as to allow easy adjustment. That's it.

I have used this on quite a few airplanes now including my Stearman glider tug and some warbirds as well as some of my Quirky airplanes. Will get a couple of pictuires up in a few minutes of my current project which is a Senior Cadet that has actually two sets of pushrods to the ruddavators of the V tail to allow control line operation as well as RC flight as well. Anyway its just easier since this one is on the table. Note the the carbon rods to the rear that come together just before the bell crank and are clamped with a pair of wheel collors.

John



Aw crawdads the picture of the tranny is a mistake, just ignore

bikerbc

Thanks for your time and Ideas fellas . I think I am getting worse instead of better somtimes . If it wasent for you guys and the guys in my club helping me I would be in real trouble .. I do really appreciate it . I think I will try too Y the elevator . I have a servo reverser that has never been used..Here is another question .If you reverse a servo with your transmitter does it stay reversed if you move it . My idea being reverse the servo instead of using the servo reverser . I am almost positive I must be out to lunch.. That would be way too easy .

golf4two

A few simple "Y" cables will suffice for ailerons, elevator and flaps. For elevators (assuming the usual install method where each servo is inserted into the fuse, one on each side) hook one control rod the top and the other to the bottom of servo wheel. This geometry effectively "reverses" the direction of travel of the control rod. There will probably be a small difference in control rod length tho resulting in differing amounts of travel so a Y cable may be a better choice. For ailerons, (verticle servo orientation) install both servos with servo wheel output toward front (or back) then attach both control rods to either outside (or inside). for horizontal servo orientation, install servo wheel both toward wingtip (or fuse). For flaps attach both control rods to either outside or inside servo arms. Frees up three channels and eliminates servo reversers. Downside is that if individual surface trim is required after maiden it will have to be compensated for by manually adjusting the mechanical linkage. Hope this helps.
G42

52larry52

My Feedback: (1)

golf4two, Now I'am confused ! I think in a dual elevator servo set up, just facing one servo forward and the other one backwards won't reverse the motion. You would need to attach one linkage at the top of the servo arm and the other at the bottom of the servo arm in order to get both servos (one on each side of the fuselage) to move each elevator half in the same direction. The rotation direction of the servo is the same with the servo mounted arm forward or arm rearward. That's what a reversing Y harness will fix. Bikerbc, If you change the direction of the elevator in your TX it will reverse both servos plugged into that channel not just one. Buy a reversing Y harness and be done with it. The reversing Y harness that I have used have a little adjustment pot you set with a screwdriver to get both servos to move the same amount. During set up, after adjusting the pot so both elevators move the same amount and the same direction, a small dab of clear silicone should be put on the adjustment pot to keep it where you put it. If in use, the adjustment needed to be changed, pop off the silicone drop, readjust, and resilicone. They are easy to use and adjust.

golf4two

52Larry52: Mea Culpa, Went back and actually looked at what I did to my Edge. You are indeed correct about elevator. Corrected my post above in case someone new reads it. Flap and airleron solutions are good though.

BarracudaHockey

My Feedback: (11)

Reversing Y's are a no-no for Spektrum.

52larry52

My Feedback: (1)

golf4two, No apology necessary. That's the purpose of this site: We all chime in with our information we believe it to be correct, then others help us get it right . It's a learning forum for all of us. Hay BarracudaHockey....speaking of learning...I would like to know more about "Reversing Y's are a no-no for Spectrum". I am an old school 72 mhz flyer who just purchased his first 2.4 equipment (DX7s) and will be installing it in a plane for the first time soon. This plane doesn't have dual elevator servo but others down the road might. What's the deal?

52larry52

My Feedback: (1)

bikerbc, You may want to hold off on the reversing y until we hear what BarracudaHockey has to say about them being a No-no with Spektrum. I think the jury is still out on this one. Stand by.

BarracudaHockey

My Feedback: (11)

Hmm...it was on a page called BEST PRACTICES that's gone from the Spektrum site but here's the warning from the manual, reversing Y's and leads were in the text of the original warning

BarracudaHockey

My Feedback: (11)

Here it is, click on the DON'Ts

http://www.spektrumrc.com/experience...practices.aspx

52larry52

My Feedback: (1)

Thanks, I clicked on your links and there it is in print. I took a quick look in my DX7s instruction manual and found nothing. I will try to read it in full tonight. Not sure what to advise bikerbc to do as his is also a Spektrum system. The link I clicked on said to use a "reversed servo", don't know how easy that will be to buy. See why I'am still flying 72mhz !!! KISS

JohnBuckner

My Feedback: (1)

Ken-----Can you let us know where the servos are located in this airplane. I checked the web site but you cannot tell from that? Are they to the rear on the sides of the fuselage just ahead of the stabilizer or are they forward in the normal wing compartment area?????

John

jw0847

Sounds like a good application for one of those sbus receivers and servos. Of course if money is no issue... Would be fun putting it together though.

http://www.hobbyking.com/hobbyking/s...inPort_Rx.html

oliveDrab

I'm faced with having to use a Y connector for my flaps. Will use a non-reversing Y connector which means I have to somehow reverse one of the servos. I bought a "HFP-25 Hitec Digital Servo Programmer and Servo Tester". It's still in the box, haven't used it yet.......but I'm hoping to use this gizmo to reverse one of my flap servo's.

BarracudaHockey

My Feedback: (11)

If you have Hitec digital programmable servos, that works fine. Some models offset the flap servos correctly so that one doesn't need to be reversed.

bikerbc

They are mid fuse one on each side John ,with the rudder servo seperating them .

bikerbc

Yes you are right I am going to rethink my plan to go with a servo reverser . That sounds like it could lead to disaster . I have already lost one PA18 . If I bent the push rod I migh be able to go off the other side of one of the servos ..I don't like doing that but it might work

BarracudaHockey

My Feedback: (11)

Get a Matchbox (smart fly has them in a two pack now)

That is the safest method and will let you adjust the direction and end point of each servo.

bikerbc

What the heck is a matchbox ?

bikerbc

Oh Okay I googled it .. I will need to change my servos to digital I guess but I think thats the answer .. Do I need to be trained to operate it ? Thanks Barracuda

BarracudaHockey

My Feedback: (11)

Nah they are pretty intuitive, and you don't need digital servos with them.

bikerbc

I ordered a twin pack from my local hobby shop .