hoppy

I'm building kit number two and I have a question for you experienced builders.

On the first kit I made the wings exactly 2 deg dihedral. (at least per the guage SIG supplies). Well this time around, my first wing panel for some reason came out somewhere between 1 deg and 0 deg. Assuming I can make the 2nd wing panel the same, how will the wings go together with the supplied diehdral support brace? How will the flying characteristics change?

Thanks.

TerrellFlyer

might lose some stability,maybe more cross coupling in knife edge and turns,Ollie in aerodynamics can probably give you a better answer,might check with him.

Flyfalcons

You can also glue a shim to the root wing rib and sand to get back to 2 degrees. The shim can be made from 1/16 lite play or similar.

BillHarris

The problem with a dihedral gauge is that a few thousandths at the wing rib can mean a big difference in the angle.

As noted, shim the "root rib[s]" with lite ply or hard balsa. The strength of the center joint comes from the dihedral brace and the 'glas skinned center sheeting.

Dihedral is necessary here. There are two types of dihedral: physical and effective. A high-wing aircraft has a positive effective dihedral due to the high wing position. A mid-wing a/c has zero effective dihedral, and a low-wing plane has a negative effective dihedral (anhedral), all due to the wing position. The physical dihedral of the 4* is necessary to compensate for the anhedral fo the wing position.

Great flying plane. I've got one that I'm gettingback in service, powered with a Thunder Toger 91 four-stroke.

--Bill

hoppy

I assume you mean to cut out a piece of ply or hard balsa the same shape as the W1 rib and then sand it? If that's the case, I really don't know how to sand it so that I keep it uniform for the entire face and still get the angle. If that's not what you guys mean, could you help explain it some more? Also, wouldn't that make that wing longer than the other wing?

Thanks.

TerrellFlyer

Hi hoppy ,no just make a wedge to go in the gap needed to get the wing dihedral

hoppy

TerrellFlyer, If I make a wedge I would have to make a cut out in it for the dihedral brace. I think there might be some gaps between the W1 ribs that the wedge wouldn't take up because of the dihedral brace and the fact that as the gap tapers, the wedge won't taper that much.

I guess what I'm asking is that if I put enough epoxy in the gaps, would this be ok?

Thanks for you help, I really appreciate it, just when I think I might be getting good at building and flying, BANG on both...

TerrellFlyer

If I need strength while filling a gap I'll use milled fiber glass.Mix it with 30 minute or slower epoxy to make a paste,makes a super strong joint. DON'T USE MICROBALLOONS,a small jar of milled glass cost less than 4 bucks.

TerrellFlyer

On a mistake ,remember.Sometimes even Betty Crocker burns a brownie. Landing really bad in the Cayman Islands,that is what the pilot used as an excuse.

Flyfalcons

Hoppy, put the wings together and note where the gaps are. Then take some thin balsa or light ply and sand them to fit and fill the gaps. Use a liberal amount of epoxy like you normally would joining a wing and insert the shims and you will have a full strength wing.