trpastor

I'm building a sig four star. I did a balsa cowl, sheeted the deck, and I'm increasing the rudder size. I was thinking seriously aobut sheeting the wings. Have you done this? How would I do this (the wings are already built up)? I'd obviously have a step down from the sheeting unless I notched each rib or something?

Would the weight be an issue? Changing the airfoil an issue?

Thanks
Tim

daveopam

My Feedback: (9)

You could, but what would be the plus side?

david

MinnFlyer

My Feedback: (4)

I have sheeted wings that only call for cap strips, but since the 4* doesn't use cap strips, it would be a major undertaking.

I wouldn't bother - it's more work than it's worth.

Now, what you COULD do is to make a template of one of the ribs and think about cutting a foam wing sometime in the future [8D]

FlyDan

Hi, Why are you changing all these things on the 4 Star?????The only one I can see would be a cowl.They are great flying planes as they are from the kit, why change a great flying airplane. You are looking for trouble as the planes performance will suffer.Dan

Andrewmc

I sheeted the leading edge of my 4* mainly for the experience partly for the aesthetics. The standard 4 star wing while it seems flimsy "in the bones" once it is covered is extremly strong.

At the stage you are with the build now you would have to trim each of the ribs and this would be difficult to get them all done exactly the same, you would also probably break a few, so I would leave the wings as is.

Nice job on the cowl though.

Campgems

I've got 4*60 #3 in the garage ready to build. I looked at the sheeted wing, and what you would have to do is to cut all of the ribs to fit the outline of W1 and W2. You could then sheet the wing without any problems. As stated, the wing is very strong. My last crash turned the fuselage into toothpicks but the damage to the wing wasn't beyond repair, I punched the front at the fuselage back about 1 " and I was unsure how much hidden damage there was, so I finally trashed it.

The only "fix" I would do to the wing is sheet the LE. Those little 3/16 sub spars snap on a regular basis. I crunched three bays worth bring the wing into the house one day. The wind caught the wing and I squeezed down on it by reflex and snapped two on the top and one on the bottom. Even without the "fix" though, and with the damage to the center, breaking the wing up for the trash can was dificult. It is a strong design.

Don

mikegordon10

I had a 4 star 40 that was built as a club racer. It had a Rossi 45 with a pipe on it. Extremely fast. When I was Sport flying it, not racing, I took it way, way up and then streaked down. I'd guess it was going way over one hundred mph. Level it out about 10' off the deck and the wing just kinda exploded. It wasn't like it broke in two pieces it was more like it desenaragated. I always thought that if I had sheeted the leading edge of the wing it may not have done that. Maybe maybe not. In any case it was a clear cut case of exceeding the flight envelope it was meant to fly at.
I guess I'd consider what engine your going to use and how you intend to fly it. As a sport model there is nothing wrong with the origional design. It's tough to beat any of the Sig 4 Star models.

DavidAgar

My Feedback: (108)

I would have to go with the what are you going to gain by doing it. The 4 Star are so sweet as they come out of the box, why mess with what works. Cover what you got, and enjoy one great flying plane. Good Luck, Dave

sensei

I think I would get rid of about half the wood in the entire airplane and make it even more fun to fly...

Bob

Gray Beard

My Feedback: (-1)

I sheet the turtle deck because that is an area that gets broken a lot when you have the plane in a rest assembling it, sticks break. I have also sheeted the LE on the wing, that's a spot that tends to get a lot of cracked ribs and fingers poked through. For what the 4* is designed to do it is a perfect little flying machine but tend to get a lot of hanger rash. I have seen a lot of them with sheeted LE but never spotted one with a fully sheeted wing. I see no reason to fully sheet the wing but building is fun so go for it.

gboulton

My Feedback: (15)

I've seen one, but it had foam wing cores as Minn suggested above. And lord knows, I'm a HUGE foam wing fan. *heh*

Rcpilot

My Feedback: (78)

Don't bash a 4 Star kit? [sm=confused.gif] Thats 1/2 the fun!!

I wouldn't bother to sheet the wings. If you were going to sheet them, should have cut new ribs before it was all framed up.

The only way I'd consider sheeting a 4 Star wing is if I planned to cover with fabric and then paint. You can even use Koverall and paint it anyway.... without the sheeting.

But that balsa cowl does look cool and I like the sheeted turtledeck. Now put some counter balances on the elevators. Then beef up the landing gear block and the back of the wing saddle area. Those are known weak areas in all the 4 star series. Cut the canopy back so it just barely coveres the instrument panel. Makes the nose look longer.

Campgems

One more weak area is the fuselage at the LE of the horziontal stab. I tip stalled on landing with my last 4*60 at about 3ft off the runway, Right wing tip hit the runway, the plane then spun on the wing, smacking the spinner almost straight down into the asphalt. At that point, I watched the whole tail snap off. It never touched the runway until it stopped, but the snapping action of the wing tip, then spinner hit snapped it clean off. A little tri stock and some epoxy and it was flying again the next day, but I still think I didn't get the incidence correct getting it back together. It always require up elevator trim after that.

The problem with the structrual areas isn't so much the design as the lite ply in some of the pieces. Doing some post crash test, I found some of the lite ply was weakest across the surface grain vs along it. I could take a pice, 1" square, and easly snap it in half with my fingers bending it across the surface grain but not along the surface grain. When you looked closely at that ply, the two surface layers only accounted for about 15% of the thickness each. Other lite ply I've looked at has a more even layer thickness and that ply is near even on strength, but slightly stronger acoss the surface grain. The good thing is that some pieces of 1/4 tri stock along the bottom/side joint stiffens things up enough to take some hard landings without adding much weight.

Don

Roby

IMO ,sheeting the wings isn't worth the effort that it would take.

If you want to upgrade a 4* put the effort into beefing up the
landing gear system. It becomes a bit weak over time.


Regards,
Roby

sensei

The most important thing about sheeting your wing on a small airframe is that it is going to add weight, and weight is the enemy. Keep it light and you will be much happier with your airplane.

Bob