SIG KOBRA
 

Im busy building my first kit , a sig kobra.
can i get some pics posted of members (of the planes) built them for colour scheme options?
Im thinking blue and yellow detail so far.

Also im still deciding on a motor to use . I have a thunder tiger .25 at the moment planned for it.
Not worried about speed that much.

RE: SIG KOBRA
 

Here is mine.
used blue white and mettalic red.
for stripes monokote red sticker (no metallic avilable).

I'm flying it with an os 25 la, had one laying around.
takes a little time to speed up...
I recomed to use small wheels on it. against drag.

The only problem with this plane, is that it is sensitive to winds (light whight).
I've added a little fin on the bottem to improve it's stablity. (and it works).

A very fun plane to fly.
[8D]

RE: SIG KOBRA
 

its always good to see some more of these being built. i love mine and its going on its third season this year.

check out this link in the "verse" for more info and pics.

http://www.rcuniverse.com/forum/m_44...tm.htm#4520110

RE: SIG KOBRA
 

Another thread on the Kobra, from the Classic Pattern Forum:

http://www.rcuniverse.com/forum/m_50...y_kobra/tm.htm


Mark

RE: SIG KOBRA
 

My Kobra is in the above thread done up in the Blue Angels color scheme. It's a real pretty plane but it can get VERY hard to see depending on distance and angle to the sun. I've got myself into a few tense seconds of disorientation. The plane is small and even with just a 25 in it, once you get it in the air it can really move. Those seconds felt like a lifetime.

The .25 in it is fine for flight, just make sure the grass is short. I had a .25LA in mine at first but replaced it with a S.T. G34. The .25 just didn't have enough to get it reliably in the air without a very long takeoff run. The plane is a ball to fly, you're sure to have fun with it.

Dan

RE: SIG KOBRA
 

Anyone built a SIG Kougar? I have one to build and was going to put a .40 in it. Looks a lot like the Kobra but bigger.

RE: SIG KOBRA
 

Elecfly, here is a pic of my buddies kobra. It was 7 years old and after a 4 year break from RC he went through training and solo again
and then started flying the kobra again. It was lost a few weeks ago during a 5 foot inverted flyby he forgot up is up when inverted.

RE: SIG KOBRA
 

luckily we have a nice tarred runway , im also putting on small wheels for the drag.
Im almost finished with the wing now , just needs final sanding and cover prep .
ive started with the fuse , got the motor from a friend on friday and needed to complete the firewall before proceeding with the fuse.
Will post some pics this week of what ive done so far. Im very excited as this is my first kit . lhs guy says my wing is built spot on , inspires alot of confidence to continue!

RE: SIG KOBRA
 

My wing is almost finished , torque rods installed , just need to align them, ailerons are ready to be covered.
just need final sanding on the wing and then it ready to cover , until the rest of the plane is finished.
Started with the fuse , now busy with the firewall , might need to build a new one . Im going to use a OS 46 LA instead of the TT25 pro.
So the engine mounting might be wider, will see and test fit when I get the motor.

RE: SIG KOBRA
 

YO ELECFLY,
STILL NOT TOO latefo retracts. modified mine after first year of flying and they really increase THE SPEED when cleaned up, especially with the 46 your putting in. going up to a 51 super tiger this year, glassed the center of wing and recovering the wing.
just a thought, should do fine with the 46, should land hot.
peace

RE: SIG KOBRA
 

frinkinstick ,
can you post some photos of youre servo and radiogear install in the fuse please ,
also , did you use the recommended pushrods? im thinking about using laser rods , I just cant use the dowels , makes me nervous

RE: SIG KOBRA
 

elecfly,
give me time and i will get you the pics posted here. got to tracel this week and no time to get the pic and then post.
anyway, i built the first fuse according to the plans and used the push rods as suggested. they were fine for the 25-35 engine range but i a little sluggish when you put it in a dive and really picked up speed the elevator became sluggish. SO, after a high speed landing i had to rebuild the fuse and tried 1 inch longer and a half inch wider, i used the originalformers that remained and enlarged them slightly to give me a half inch overall (formers+new fuse sides=1/2 inch wider than plans) and let the extra in longer come out the back end of the fuse. this allowed for the center line to remain the same and the wing to be mounted exactly like the plans.
low and behold i had plenty of room to get inside the fuse this time. i forgot to mention that it is extremely tight "by the plans" and hairy close when you mount the wing with the aileron servo having to fit between the mounting lugs and the rear part of the saddle. it works but barely. on my second fuse and if i may suggest, i modified the wing for individual ailieron servos. i know from your post above the wing is already done but i modified mine after many flights and it really wast that hard. the trick part is getting the original torque rods out of the trailling edge in the center. luckily i got mine all the way out, drilled holes thru the ribs to run the extension thru the servo bay for the original wing servo and connected them both with a Y harness. the reason i mention this is if you have already completed the fuse and need some extra room this might be an option to think about before covering. it also provides for super response at all speeds. i like your idea of using laser rods. they will work much better than the pushrods the kit comes with.
as soon as i get a chance i will post some detailed pics for you on my mods. last year i clocked at 108 with a 40. you should be in that range with your 46.
let me know where you are in your build, and if you have any other questions.
frik

RE: SIG KOBRA
 

After about two months of working hard and studying and exams and stuff I started building again, Fuse is off the plan and dead straight, im very impressed with myself on the straightness of everything, I took my time and it paid!

I started with the tail feathers last night ,
next step on the fuse is the tank and wing mounting blocks, then front wheel and throttle pushrods and planning the servos inside the plane,

im gonna make the cover under the tank removable for maintenence if neccesary.

Its looking good sofar and im really excited.

The TT.25 is still my planned enjin for now, the 40la sale didnt work out.

See the attached pictures , please feel free to comment on anything

RE: SIG KOBRA
 

Tail feathers finished last night , Planned all the radio gear for the throttle and nose gear and rudder.

Gonna buy some servos today and that will go in this evening.

Will be able to steer it when i push it by tommorrow.
This is also my first model with trike landing gear config.

RE: SIG KOBRA
 

Last night I installed the rudder/nosewheel servo , nosewheel pushrod, throttle servo and pushrod,
and the aileron pushrods.

The Tank is in , no fixed yet but i had to get it in too see where my pushrods can move.

Motor is on temporarily until all hardware is installed

RE: SIG KOBRA
 

Some more progress through exams....

The wing mount is on, with blind nuts on the back.

Laser Rods Guides are glued in and the top of the Fuse is sheeted except for where the laser rods were glued in the middle of the fuse.
Still need to sheet there. I experimented a bit with the sanding of the fuse,see in attached pics where the corners are rounded.

The Rear wing and elevator has been covered, my first ever covering job. Didnt come out to bad i think.

Comments and suggestions and tips please

RE: SIG KOBRA
 

Some slow progress the weekend.Weekend after exams is always slow!

Got the tank fixed in the nose, the top of the fuse is sanded , i bought wheels , nice rubber ones. Idont like the foam, they get flat spots when they stand for a week. But i couldnt find a damn yellow spinner!!! my colour scheme depends on it! why me!

any way that can wait. i have decided that i am not going to close up the cowl. its 2 small in there and i dont have the motor im gonna use yet.The fuel tubing is also in and the whole front of the plane is fuel proofed with epoxy

attached some pics of the progress

RE: SIG KOBRA
 

Last night was spend on some detailing in the cockpit, I printed an instrument panel and added some balsa in the back.

All still needs to be painted black . Next is a headrest/seat type thing for the pilot.

I also finished the top part of the fuse, it came out pretty good, i was scared of starting with it.

The front of the fuse is going to be covered in yellow, maybe yellow and blue checkers. The ideas are just popping into my head now and i dont want to overdo it.

RE: SIG KOBRA
 

Would someone on this thread be kind enough to scan or trace the dihedral gauge for the Kobra and post it here? I'm building another wing for mine and don't have the gauge anymore. The Kobra met an unscheduled inverted landing. The fuse survived almost unscathed but the wing, well let's say I was picking up pieces of blue Monokote out of the field!! This one will be finished F16 Thunderbirds style and the King Kobra kit I just got will be back in Blue Angels scheme.

Thanks much,
Dan

RE: SIG KOBRA
 

Anyone know of someone doing an electric conversion with this kit?

RE: SIG KOBRA
 

See this thread:

http://www.rcuniverse.com/forum/m_37...tm.htm#3800406

RE: SIG KOBRA
 

I'm building one just for racing right now. The wing is finished and I just started the fuse. I have two HT 81 in the wing for aileron control. Ailerons were shortened and I turned it into A tail draging beast. A WEBRA 55 for power with A tuned muffler system. Retracks would be nice but the rules say I can't have them. I'm building very light too.
This little guy should haul mule!!!!!!:D:D

RE: SIG KOBRA
 

Gray Beard, What are you doing to keep it light? Mine came out a bit portly at 3lb, 9oz. What weight are you shooting for?
Sounds fun, MikeB

RE: SIG KOBRA
 

I never shoot for any weight when I build. I just build the kit then grab the hole saws and drill bits then remove anything that isn't in A stress area. The wing is not stiff enough for racing out at the ends so I put in the shear webs all the way out then removed the centers. I have them set up like I-Beams. It worked and the wing is stiff now. There is A lot of area in the fuse that can go too.. I did the same thing to the Kaviler I built for that class. You don't need all that heavy sheeting on the wing and fuse sides.
All these planes are built for is racing, go fast and turn left is all they do so the stress areas are easy to find and stay away from. I also use A lot of my own contest grade wood, much lighter.
Sig makes A great kit but there wood selection leans to the heavy side and the design is made very stout. They can take A heavy hit, mine can't. ;)

RE: SIG KOBRA
 

Here are a couple of pics from my Kobra re-build. Well maybe not the 737....

Dan