RE: Nitro Models Kangaroo Mods - Sheeting
 

OK... More progress.

Rudders are shaped, smoothed, covered, hinged and installed :p (that was fun to say)

Elevator is covered and hinged. (Wish Id found the metallic blue monokote that I used on the wing stripes before I put the black one on, but it looks nice anyway)

RE: Nitro Models Kangaroo Mods - Sheeting
 

funny how things can end up working out. Earlier I came up with about 5 options for the nose gear door/opening. I ended up going with option 6 :p

I just attached my piece of "fiberstuff" to the bottom of the fuse over the opening with screws, and cut it out just enough for the wheel to come out. It was simple, and Ive seen similar on other fast planes, so I reckon it wont cause too much drag. I plan to paint it to match as close as I can to the bottom after I finish the monokote. (the pattern may cross the cover somewhere, havent crossed that bridge yet :P )

I also sheeted in the Main retract wells with balsa, as I wasnt able to get the plastic ones to fit, and they didnt match the yellow anyway :p

RE: Nitro Models Kangaroo Mods - Sheeting
 

Ok, got the monokote on the bottoms of the wings. I think it will contrast nicely from the top now.

This thing is starting to get really close. I still have a lot of work to do as far as installing the radio gear and engine, but I am starting to see the light at the end of the tunnel. I am even having fantasies of having it ready this weekend. Now if only the weather will cooperate.

RE: Nitro Models Kangaroo Mods - Sheeting
 

Very Nice! Looking forward to hearing the flight report.

RE: Nitro Models Kangaroo Mods - Sheeting
 

Still making some progress... Plane is all covered, Pics soon.

Was stalled however by a radio problem. I need the P-Mixes on my transmitter to make the dual elevator servos work, and the mixes are broken :(

Problem solved however, ordered a Futaba 9C to replace my 7C (which I will give to my dad) Now I will have enough channels and mixes to have this thing set up the way I want without aving to y-harness too many things :D

Staying with 72Mhz for now... Never have to worry about Freq conflicts since where I fly there are at most 15 people there on a "fly in" type day, usually just me and my dad, or a friend. And I saw a $6K Plane get destroyed when the RX was interuppted (or something) by a large radio beam that runs nearby our site. The signal was apparently lost, though the engine did not go to idle as in normal fail safe, and the TX/RX could not re-aquire signal before it went in. I could be wrong, but as I understand, he had has the same thing happen on a 72 Mhz PCM reciever a few weeks before, (lock out with no idle) but as the plane obviously survived that one I assume that the TX/RX picked up immediatly after the plane came away from the "Beam"

RE: Nitro Models Kangaroo Mods - Sheeting
 

I have about 8 planes on FM recievers now but just bought the Futaba spread spectrum 6EXA FASST transmiter and reciever for the mustang that I am building. I plan to slowly transition into spread spectrum as the prices come down. The Futaba receivers are going for about $90 but you don't have to buy a crystal. They do have fail safe and eliminate the possibility of having your Tx set to the wrong model. I'm still buy 72Mhz single conversion receivers for my small electrics. Century Helicopters has them for $18.50 for receiver and crystal.

RE: Nitro Models Kangaroo Mods - Sheeting
 

OK! New radio is Awesome! It has a couple options for using 2 servos on 1 surface. There is a dedicated function for it, but you cant use that and the Elevon function at the same time, so I used a P-mix on the elevator. Actually, 2 mixes; one of the elevator servos is slaved to the elevator part of the elevon, and the 2nd elevator servo is slaved to the first. I made some paper protractors to get them lined up properly. I also have the nosewheel steering servo slaved to the rudder channel. that way I can trim it individually using the sub trims, and it turns off when the wheels retract. This not only saves a bit of power, but makes it so the nosewheel cant turn as the wheels come up if I hit the rudder. If the wheel turned much, it would jam going into the body. (I know because it already happened ;) )

RE: Nitro Models Kangaroo Mods - Sheeting
 

All servos, the Retracts, and the engine are fully installed now. Im almost done with the wiring, only have to wire the retract servos together and Im all done. I counted it up, and there are 45 solder joints in the wiring for this plane. My Dad gave me a neat battery powered soldering iron for christmas, which made the job go smoothly :)

I Used a 9 Channel reciever, and set up the channels as follows:

1: Right Aileron (Elevon #1)
2: Left Aileron (Elevon #2)
3: Throttle + Battery#1
4: Right Rudder + Left Rudder
5: Nosewheel Steering
6: Elevator #1
7: Elevator #2
8: Main Retracts + Nose Retract
9: Battery #2

Im going to start with a pair of brand new 4.8v Nicads (600 & 700 mah). The weight of those combined is only about 1/2 oz heavier than the single 1650 mah NiMh that I have in most of my other planes. I wanted to go with the 2 batteries with this plane both for redundancy, (because it will be fast) and to spread out the current draw over the reciever because there are so many servos.

Ive been debating during this whole process what to do about the Muffler. backwards, the stock one points the output tube into the wind. Not only that, but now there are servo openings behind the engine that I would prefer to keep oil out of :eek: I went with a length of gas tubing for a car that I had laying around. it fits right over the end of the muffler, passes through the wing, and sticks out about 2" from the bottom of the wing. I only had to go through sheeting to do it, so it it doesnt work out, Ill just monokote back over the holes :p I am hoping that the oil will mostly just shoot straight down when the plane is upright, and not get onto the rear too much, but even if it does, now its more in the center away from the servos. Sorry I dont have a pic of the bottom, my camera is sort of dying, and it wouldnt take any more pics ;)

RE: Nitro Models Kangaroo Mods - Sheeting
 

Our club had its annual "Freeze fly" yesterday, and I got to take up the new plane for a few rounds. Actually, the weather was quite nice. 50-60* and hardly any wind.

After some tuning (and some exciting aborted takeoffs) we finally got the engine running well. Seems at some point I adjusted the idle mixture way too lean. Its an Evolution 46NT running an 11x7 APC Pusher. The engine seemed to produce plenty of power in the air, and flew the plane much faster, and with a better climb rate, than the OS 46FX on my H9 Raptor. The takeoff runout was almost as long as the Raptor's however... I think an 11x6 would give me better thrust. I also want to try the 10x7 3 Blade MAS I have on the raptor, if I can find a pusher version.

I wish I could say it took 2 clicks of left and 1 click of up and it was perfectly trimmed, but I seem to have not reached that point in my flying career yet :p This is, I believe, my 10th plane, and my experience has been more along the lines of 8 clicks right, 7 clicks up, and some rudder for good measure ;) Not sure yet if it's my balancing, or just that after a while you can anticipate which way the trims will need to lean... but someday I'll get there ;)

Once I had the plane trimmed out, it was Awesome! The ailerons are very sensitive, and I had to dial them down a bit after the first flight, which was a little scary [8D] Im really glad I went with the elevons + the elevator in the middle, instead if just the elevator. Using almost all the throw I had made the elevator feel just about perfect. I will try moving the balance back just a bit and see how that does, but the balance in the manual seems to work out very well. Actually, the balance point is all I used the manual for, after reading it through the first time, and seeing how bad it was. (the plane is great though)

The rudders were a great add on. The plane tracked really straight, and the rudders hardly cause any rolling action. (finally got the rudder/aileron mix dialed on the raptor, takes 24% opposite aileron to make up for the rudders on that plane, can almost do a barrel roll with them....) On landings, they helped make up for the slight crosswind that seems to always be present.

This thing is FAST! I mean, looking at it, no one would mistake it for a slow flyer... but I was amazed at how fast it ate up airspace. I know its not even as fast as a jet, but its definitly the fastest thing Ive ever flown, and it gets the adrenaline going :D It also flys slow fairly well too, though I cant give an accurate account of the stall behavior yet. By the time I finally got around to trying a stall test, I had flown the airplane a few times, and little did I know, parts were starting to come loose. I went up high, dropped to idle, and started feeding in up elevator as the plane slowed down. I got to where I was holding full up, the plane was kind of wallowing along, wandering a bit left and right, then all of a sudden the plane dropped off to one side and fell like a rock. Fortunatly I was high enough, picked up some speed and pulled up, no problem. Flew around for a few more minutes and came in for a landing. As I was taxiing in, I noticed that the left aileron pushrod was trailing along behind the plane, having come disconnected at the servo end. (the screw holding the ball link came loose) The funny thing is, I never noticed a loss of aileron control, even as I was slowing down for my landing approach!

Landings are much easier than I was expecting. the first time, I gave myself lots of room, figuring it would come in hot. I ended up setting down almost 200' earlier than I was expecting, and rolled right up to the pits, rather than driving back from way down the runway, like I do with the Raptor.

All in all I am really happy with this thing :D At some point I would like to put a different canopy on it, but for now I have so many other plane projects waiting I will just fly it as is. Time to decorate it up all the way and put a name on it though. ;)

RE: Nitro Models Kangaroo Mods - Sheeting
 

Congratulations on your maiden flight! Sounds like she really flys nicely. We had 10-20 mph winds and 40* temperatures at our freeze fly here in Pennsylvania but flew anyway. I also lost an aileron servo on a Carl Goldberg Matrix (servo failed) and was able to land without to much problem. I like the orange covering you put on the bottom. Let us know how you make out with the prop change and balance. Just about finished with my Mustang and getting ready to start my Kangaroo.

RE: Nitro Models Kangaroo Mods - Sheeting
 

Well, I have 10 flights on the plane now, so I thought I'd post on how its been going.

I started out with an Evolution .46nt and a 11x7 APC. That combo really had ample power, and I probably would have stuck with it, except I decided I wanted that engine for another plane. I put in the OS .60 SR (ringed) that I had laying around, and was going to use if the evo wasn't enough. I had to shave a bit of the mount to get it in there, but it fit rather nicely in the end. I also enlarged the prop slot in the body a bit, to accomodate a 12" prop. With the gear I'm using, theres plenty of clearance already.

The new (actually old, but came to me NIB) engine runs really well, considering it has the needle valve assembly from an Evolution .46 on it... (the stock one having snapped off in the demise of my rambler...) Amazingly, considering the 20 year difference in production, and the different manufacturers, it screwed right in and worked fine. I also modified the muffler, so that the output tube is at the "back" now, blowing right through the prop, and the stock hole is closed up. I would post pics, but my camera is toast, and I have yet to get a new one. The increase in power isn't huge, but very noticable. Takeoff run is cut in half at least, and theres lots more climbing power. Almost unlimited vertical on 12x6 prop, not the best speed; the 11x8 was better for speed, and a bit less on vertical, but still very respectable.

Im finally getting the hang of landing it. I thought I needed to bring the H9 raptor in fast... I need to be moving pretty good in this plane or I can't keep the nose up. It feels nose heavy there, but seems fairly well balanced in flight, so I not sure what to do yet. I can't practically get any more of the gear moved back for balance, so I will have to add weight to move it back any more. (already have a heavy hub on the engine) But as long as I keep a few clicks of throttle on, it seems to be ok. I wish I could put the Oleo struts from my stang on there though :p but theyre too long by almost an inch. I tend to hit pretty hard sometimes, and the wire gear are bending. I have to check them every flight to make sure they wont bind when I retract them.

If I had it to do over again, I would have completely recovered the plane in yellow, with some good markings. All the black and silver makes it sillouete really easily, and as its fast, it gets out there pretty far. Unfortunatly with all the funny joints around the prop and elevator, it would be a lot harder to cover now that its all stuck together, so Im going to go with it for now.

All in all its a fun plane :) Certainly gets my blood racing....


By the way, if any mods read this, and think it would belong better in another thread, please feel free to move it. I put it here originally looking for tips on the mod to the body, but it's maybe not the best place for the thread...

RE: Nitro Models Kangaroo Mods - Sheeting
 

Nice mods, I have reasonetly built a Kangaroo 46 nitro to electric conversion... I am all electric. Can't wait to fly it at the field. 6s 2250mah, 50/55 500kv, 11x10 prop. I am trying to attach pics but when I try to upload they finish but when I preview they are not there? well I will post this and see what happends. Matto

RE: Nitro Models Kangaroo Mods - Sheeting
 

Looks good! Much more sleek without the engine sticking up over the body. Actually kind of looks turbine like, that outrunner is so big :p

I bet it will scream with that prop, cant wait to hear how it goes :D

RE: Nitro Models Kangaroo Mods - Sheeting
 

Well I finally started building mine after all these months. I'm going stock with fixed gear and OS 46 FX. So far I have the folling to report:

- Covering is very nice
- Wing and stab fits were good except supplied dowel pins are to small
- All servo holes had to be enlarged
- Nose gear blind nuts did not align with holes in supplied nose gear block
- Main gear blocks were to small for openings - had to make larger
- Motor mount holes did not line up with preinstalled blind nuts
- Fuel tank and nose gear block are difficult to install - poor access
- Since this is a pusher - I installed the tank with the stoper facing back but installed a brass tubing "U" bend inside tank so klunk is at stopper end of tank.

Here are some pictures....

RE: Nitro Models Kangaroo Mods - Sheeting
 

Well, I'm about 95% complete. I attached some photos. I built it pretty much stock. I was able to get close to recommended CG by installing battery (1450ma 4.8V NiMh) behind the nose gear and throttle servos. It's still slightly nose heavy. I figure this is a good starting point. Canopy is very brittle and sits high on front leaving a gap. I was affraid to heat it so installed some wing tape under the front flange. Still have to figure out how to route the antenna. I might glue a carbon fiber tube along the leading edge of the wing and thread it through. Any ideas? I'm using 72 Mhz receiver. Also need to seal fuse under the engine (OS 46FX with 11X6 APC pusher). Had to install larger wheels to get adequate ground clearance for prop and grass field flying. I'm planning on using elevons and elevator. Anyone fly one that way? In general, access to fuel tank and nose gear is tight. I had to come up with some innovative ways to avoid cutting hatches in the fuse. Probably won't fly it until the spring.

RE: Nitro Models Kangaroo Mods - Sheeting
 

Nice to see it almost ready to go! I am sad to report mine was destroyed a while back.... I'm not exactly sure what happened, right after I dropped the gear for landing the plane spun out of control and went in. The wreckage was too extensive to be sure of the cause, but I did find that the fuel tank had been leaking for a while, and had even gotten into the wings.

What I did with my antenna was to run a piece of plastic tubing from one wingtip through the wing into the body, following the "d tube" area at the front of the wing, it comes out right behind the radio area. The antenna didn't quite reach to the tip of the wing, so it wasn't viable at all, but worked great, and is far from the prop.

I used elevons and elevator, and it was great. In fact, I wouldn't recommend using just the elevator, as the extra authority was really welcome.

Mine flew great with the 46, though after 10 or so flights I upgraded to a .60 I had around, as I needed more weight in the rear anyway, and then it screamed! Looking forward to a flight report :)

RE: Nitro Models Kangaroo Mods - Sheeting
 

Sorry to hear about your Kangaroo! You did a beautiful job on it and had very nice mods. I can appreciate all the work you put into it after building mine. Especially the access to the fuel tank and nose area. I built a platform under my tank before gluing it together but was not able to get much foam around it. Hope my tank holds up! Thanks for the info on the antenna - sounds like a good plan. Did you use the throws suggested for aileron and elevator? I will go with elevon and elevator per your recommendation. I used cheap mini servos from Hobby City on the elevator and am not sure how they will hold up. Elevons will give me some additional security. I'll let you know when I maiden it. Probably post a U-tube video also. Weather is very cold and windy out here in Pennsylvania so we are doing almost no flying. Are you aware of any flight videos on this model?

Thanks!

Eric

RE: Nitro Models Kangaroo Mods - Sheeting
 

Attached UTube video link from mymaiden flight. Iflew with 10X6 APCpusher prop, OS46FX,elevator and aileron control.Not enough elevator with this setup (elevator throw was one inch). I'm in the process of converting to elevon and elevator control.

http://www.youtube.com/watch?v=7OLQLB6DO_M

RE: Nitro Models Kangaroo Mods - Sheeting
 

Latest Yuo Tube video. I think I have all the bugs out of it now. I have the elevator servos on the flap channel and slaved to channel 2. Ailerons are set up as elevons. You can see operation at end of video.

http://www.youtube.com/watch?v=894vph4ryRg