Cool! So... You're moving the battery aft, so there won't be a CG shift when the power quits?
Ha ha. Just kidding. Not to mention all the static electricity, when you wipe the plane down after a flight. That's the residual voltage.

Robert,

Is this along the idea as to what you are doing?

Yes thanks for posting this

These hinges make inset hinglines a breeze to make. Russian modelers(those that don't make everything themselves that is) have been using them for years.

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXET57&P=ML

I bought 2 sizes of these and they are not loose enough for what I am doing. So I made my own.

Robert,

Nice framing so far.

What size is your LE stock? Does it taper towards the tip?

All tapers are dictated by the spar. On a beam airplane everything is set to the spar. (bad spar = bad wing) The LE stock is 1/2 X 1 and will be shaped after all the ribs are set. I have devised a new system (at least to me). Its a floating spar. The spar floats in the fuse when jigging and is held in with clips after everything is aligned.

You're right up to speed, and it looks quite nice!

I was asked to show my hinges. I hope this picture explains how its done. I am still detail sanding the wing and getting all the little stuff done like sewing the ribs. Fuse and wing with tips is 9 ounces.


If you notice there is a C in the trailing edge and a rounded LE of the elevator. The pivot is set back 1/2 the thickness of the elevator and will act like a socket never having any hinge gap.

 Flaps are the same set up with three hinges instead of two. I have a dremel router and I used a 1/4 inch half cutter. I made 2 passes one in each side and then sanded the finish for the C.

I will add that they are at least ten times free'er than regular hinges I have used. They flop. This will be a bushed horn set up. I have tried all the modern stuff and still think some of the old ways are better for me.

So you made the hinges then? Can't quite tell, are they plywood?

Yes with brass bushings

I think the way you sew the ribs wit Kevlar thread is really cool!!  Do you CA them at the point of contact with each rib?

Yes and where the X in the center too. Weighs nothing and it 1000 times stronger than balsa

I'm pretty new to this, is that what's referred to as an I-beam wing? Is it always done with the spar installed in the fuselage?

Jim

When I do the flaps I will do a detailed photo spread. This is not a new thing its from the 40tys (there abouts) and works great.

Thanks Robert

Ken Pitts

loving them bones. Almost a shame to cover.

Ken

  Is it possible to put up a picture of this detail, or is it covered by now? I'm having trouble visualizing this.
    Thanks a lot,
   Dan McEntee

Somewhere on the other viper thread I put up a pic of what it would do but my camera is limited and it blurs.

Yes with brass bushings

  Back in the good old days, the lubrication took care of itself. Now, you have to oil them from time to time, even on piped airplanes. The hinge pin will rust if you are not careful. 

    Brett

Here is where E Viper 3 is at now.

 Heck, you oughta have it ready to fly by this weekend!

Dissimilar metal corrosion sets in and I did think of making the bushings from Nylon. But Nylon would not be as free as the bearing surface would be larger. I want floppers. I guess on the next plane I will make them from oil-lite.

I would think that the pressure of the air pushing on the control surfaces would far outweigh the drag of any standard control system. That being said, there is nothing wrong with smooth controls.

Derek

I would think that the pressure of the air pushing on the control surfaces would far outweigh the drag of any standard control system. That being said, there is nothing wrong with smooth controls.

   It's additive. I think you would be very surprised how much effect even a tiny bit of drag makes.

    Brett

Motor offset and light weights.

By all means do what you like but it seems to me that motor offset would cause more trim problems than its worth. I build all my planes strait, no rudder or engine offset and no adjustable rudder. I use leadout, and tipweight to trim the plane.

Just my .02

Derek

Would you agree that the Shark fly's well? It has 3 degrees Motor offset. Would you agree that Billy's T-Bolts fly's just as well. There again about 3 degrees. The only line tension overhead is off set.. Just my thinking

Would you agree that the Shark fly's well? It has 3 degrees Motor offset. Would you agree that Billy's T-Bolts fly's just as well. There again about 3 degrees. The only line tension overhead is off set.. Just my thinking

    It won't hurt anything too much, but the offset, trimmed tangent otherwise, gives you virtually nothing overhead or anywhere else, less than 2 ounces over what you would otherwise have. Almost all of the overhead tension comes from centrifugal force - in this case, tension = centrifugal force - weight when you are dead overhead.
   
    Most of the effect of offset is to create (or null out) the yaw torque by aiming the thrust vector so it passes inboard of the CG. The more offset you have, the more right thrust you need (because the CG will need to be offset to the inboard side of the fuselage). That's the main thing wrong with the All-American, the engine is lined up with the fuselage but the CG is well inboard, so it yaws in at you at takeoff.

    I use around 2 degrees, somewhat indifferently measured, and I have about 3/4" of wing asymmetry. It's very insensitive and of all the unnecessary offsets, thrust line offset is the least objectionable.

     Brett

I think the way you sew the ribs wit Kevlar thread is really cool!!  Do you CA them at the point of contact with each rib?

x2! Excellent Engineering.

Centrifugal force over head? Come on. The Centrifugal force overhead is less than gravity. Guess I never learn simple physics.

Since this is off-topic and further comment on it in this thread is unwelcome, I will post the answer in the Engineering section (it's that dreaded high -now middle - school math).

SK

Please do I would like to know how much centrifugal force is applied if the engine quits. I would be nice to know the amount of line pull there is overhead dead stick.

    When your engine quits directly overhead, does it fall straight down at you from the top of the circle?  Of course not, most of the time, that's perfectly recoverable.

    I call shenanigans, this time you are just pulling our legs.

    Of course, when the engine quits, it slows down pretty quickly, so you start losing it rapidly. Particularly if your airplane is too light, the drag is the same as everybody else's airplane, but the momentum is less, so it the acceleration slowing it down is higher. But you have to get down to less than half speed to get the centrifugal force down to zero.

    By the way, my satellite is dead overhead right now, and the engines aren't running, what keeps it from falling straight down into the ocean?

   Brett

I remember a few over head dead sticks. I dove out, a bit scary for sure.

Ken