I have the composite Kangaroo and this is the first plane that I have had with Elevons. The problem I am having concerns travel throws for the elevons. I have set the travel adjustment end points for the recommended distance per the instructions for both elevator and ailerons.
The problem occurs when I input both elevator and aileron to their extremes, such as full right aileron and full down elevator. The total travel distance then becomes much greater than the 25mm recommended for either the ailerons or elevator and they are binding very badly.
How do I resolve this problem? I am not sure if I am setting them up corectly with initial travel throws but they do operate properly with the stick controls as far as up/down and left/right. The travel throw just becomes excessive when a combination of aileron and elevator is used.
Thanks in advance for any help, Gary

For a fully stalled, high alpha touchdown, I would not worry about too much elevator throw on the elevons. Just set up the elevator with some expo. You do have to keep the aileron protion of the throws reasonable. Again, I like some expo there.

I had the same concern on my Roo.
I had to reduce the aileron travel somewhat, the ailerons were way too sensitive with the throws suggested.
I use about 30% expo and you'll find you very seldom use full deflection anyway, so I've never had a problem with it.
Try reducing the travel on the ailerons to about 60% of what the manual recommends.
My manual recommends 3/4 inch up and down on the ailerons.
It will roll very fast at that setting. It's flyable, but I don/t like it that sensitive.
The elevator settings are about right 1.25" up and 3/4" down in my manual. The composite Roo s/b the same I would guess.

Pete Stapleton
Simjet Rep

Pete, the settings for the composite Kangaroo are +/- 25mm (about 1") travel for the elevator and +/- 20mm (about 3/4") travel for the ailerons. This is comparable to what you are suggesting, but my main concern is when you push the right stick all the way to the corner giving both full travel on the aileron and full travel on the elevator. This causes considerable binding because the travel probably doubles and it will cause damage to the wing if I do not resolve this problem.
My transmitter is set on elevons and the travels are set to the recommended travels. Not sure how to resolve this. Thanks again, Gary

Gary,
I know what you mean, on mine just reducing the aileron travel took care of it almost completely, I still get a little binding on full travel, but nothing it can't tolerate for a short time.
What I count on is I almost never have my controls that hard over in normal flight. (never have in fact)
Maybe you need to in crease the allowable travel on the elevon some how? Probably not possible if it's already hinged etc..

Don't know what else to do!

Pete

Pete, I think you are right that decreasing the total elevon travel will help. Maybe I can try moving the links in on the servo arms to decrease the overall available Elevon travel. Thanks for the help, Gary

Oops, I see what you are asking now. When I flew Futaba, I think they had one travel setting (I forget now what it was called) that limits the maximum throw that that servo can possibly go. You could set that to the point of binding, and then even if you command more deflection due to the combined aileron & elevator throw, it will not be an issue. I don't know what you are flying, but perhaps JR has a similar function. Multiplex does, but I do not now remember what it is called.

Gary,
What you want to keep is most of the up elevator, the Roo needs lots of up to rotate with a full tank of fuel.
Otherwise like most planes it doesn't really take much throw to fly normally.
You can fine tune it after a few flights.
Also as mentioned in another post, you can limit your max travel.

How much travel do the skin hinges allow?
I put about 1/16 inch gap in mine to allow lots of throw.

Pete

You guys lost me out in the weeds. Where did elevators come from? Roo's are like big Zagi's. Elevon's do both. Im lost

Ken, they are referring to the elevator and aileron components of elevon throw. They understand that a Roo has only elevons, but it's movements can be broken down into a component that is aileron movement and a component that is elevator movement. When referring here to elevator, they are refferring to the elevon's movement when the elevator stick is moved. Hope that helps.

THANKS. Guess I never saw the over travel thing because of the way I set my elevon's up.

Pete, I have the travel throws set at the recommended throws right now and I am reluctant to decrease them further. I am going to look thru my JR 10X manual today and see if there is something in there that will allow me to decrease the overall travel for the elevon setting itself instead of trying to adjust each individually.
The reason I need to correct this is that the control horns will hit the top skin and actually bend it and damage the top skin when both aileron and elevator inputs are at their maximum travels with the sticks.
If I am unable to correct this it has the potential for not only damaging the wing but possibly binding badly enough to pull the control horn out of the wing. It is only a problem on the top of the wing. I have already increased the gap slightly between the surfaces but it is not near enough. I may need to cut a slot where the control horn moves forward toward the wing skin so it will not hit on the top skin. Hoping for another solution!!
If I do not get it resolved today, I will call Mark at Planes Plus tomorrow and talk to him. I know he has built several of these and can probably help me out. He even uses a 10X radio I think. I am still open for other suggestions if anyone else has any. Thanks for all the replies, Gary

I have resolved this problem by slightly notching the trailing edge of the wing for the control horns and elongating the slots for the linkage in the wing. It did not take as much as I thought and still looks good which was my main concern. Thanks to everyone for all the help, Gary

Way to go, so when is the first flight?
I din't know how your weather is, but it's cold here.
Be a month maybe before we can start to get a few flights in.
I needed a jet fix bad today, so I watched some tapes from last year. It helps.

Let me know how it flies, I know you'll love it.
The Roo's are just a blast to fly.
Be sure you have caster in the nose wheel.

Pete

Pete, I will be finished with all but the retracts and turbine installation by tonight. I am waiting on the engine which is on the way, and will probably order the retracts, wheels , and brakes next week from Great Northern Hobby in Canada.
You should check him out next time you need something. Their prices are great. I met Ed at Florida Jets with his partner in the business I think. They are very nice and after shopping around a little he helped me save about $100.00 on the package deal.
I have one of the Simjet 8000 kits on the way for the Kangaroo which should ship out next week sometime.
We made reservations to go to the Mid-Atlantic Jet Fly in May. Didn't know if that was one you guys would attend or not. It's not quite as far as Florida was for us, around 10 hours I think.
I will send a picture of the Kangaroo as soon as I finish it up. First flight is still a little way off, in a month or so. The weather will be changing by then and I will have both the F-86 and Kangaroo finished and ready to fly. Thanks for all the help, Gary

Let meknow what you think of the 8000 kit.
I'm thinking of building the Sonic 120 kit, thats a 26 lb'r.
Or I may get a 1200, or I may get a 700, kind of undecided at the moment.
Kind of like a kid in a candy store, too many goodies I can't make up my mind.

Pete Stapleton

Pete, your all over the map there with engine choices. You must be undecided on the plane you want yet. I have been running the 1200 in the garage on the bench and it is purring like a kitten. A really loud kitten!!
I will let you know how the 8000 works out. I ordered it with electric start also. I do know someone that has already built one and he said that you can build it in an evening. I would assume that is the probably the case with any of the kit engines since they are all the same design. Gary

Glad to hear the 1200 is running good.
Hows the manual on the 1200?

You're right, I am undecided on a model.
Seiously considering the JHH F9F Panther and a 1200.
I'd also like an Avonds F15, but everyone has one.
That 26 lb'r would go great in the F15.

Oh well, I've got plenty of time long as my Roo runs so good.

Pete

Gary, you made the right choice with the Trim wheels, brakes, and tires. Great equipment at a reasonable price. I am very impressed with them and I got my second set from Ed. He is a great guy and great to deal with.

Pete, the same manual is used for the 1200 as for the other engines. Starting and setup is almost identical I think with a couple of exceptions. Gary

woketman ,do you have a set of the Trim wheels and brakes? I only have experience with the BVM wheels/brakes but there was such a great difference in the price that I thought I would give them a try and Ed said they are very high quality.
I looked on Trim's web site and they do look very nice. If they work well like the BVM units then I will probably continue to use them. The price is definitely right!! Gary