Guillow’s Aeronca Champion 85

[BillParker]

Guillow’s Aeronca Champion 85

http://www.guillow.com/aeroncachampion.aspx

Item Number: 301
Wing Span: 24"
Scale: 1/18









Silkspan and dope next...

More soon..

bp

[PsyberPhlier]

Dang Bill, nice work.

Am I seeing right... that you left all of the dihedral out?

Ted

[BillParker]

On this one, the dihedral is provided by the underwing struts. They serve to push up the wing to the proper position, and by stressing the assembly add strength...

I'll try to remember to photo that part when I get there...


bp

[PsyberPhlier]

Was building up the tail surfaces part of the kit plan or is that something you do for? scale appearance? better free flight?

Learning here...

[BillParker]

I don't like or use tissue. I grew up with silkspan, and silkspan is what I use. I use butyrate dope, (it's fuel proof, and I do u-control) I grew up with butyrate, and it's what I use. I buy it in one gallon cans from Aircraft Spruce Co., then thin it 50/50 with commercial acetone. I buy that stuff by the gallon too.

So, I build these small structures with the interior stringers on the out side of the structure because silkspan and butyrate shrink. Turns tail feathers into pretzels... Then they shrink some more. Then they keep shrinking till the end of the plane's service life.

Example:



In actuality, I generally sheet the tail feathers with 1/32" balsa...

example:

[PsyberPhlier]

LOL I guess you don't have the problem of 'sagging skin'...

Thanks for the info, Bill.

Ted

[David Lewis]

If you have trouble with the tail warping, switching from 3/32" to 1/8" balsa will help, and at the same time increase the stiffness-to-weight ratio. (Rigidity goes up as the square of thickness.) If stiffness-to-weight ratio is not critical, then sheeting with balsa skin is a good choice.

I measured the wing span of the #301 Champ at 23.7", and the scale of the fuselage to be 1:16.8. The wings are a different scale than the fuselage. In general, dividing the span of the full size airplane by the span of the model, even if the model wing span listed on the box is correct, doesn't always give you the correct scale. In my judgment, the scale of the fuselage, especially the cabin or cockpit, governs because that's "the place where the man goes."

[BillParker]

Ha ha! I use 1'4" balsa stock and it warps up comically... I'll stay with the 1/32" cover on the small stuff...

Most of my planes are covered with cotton muslin... (think, bed sheet...)







This P-40 is between 1/5 and 1/6 scale... The little ones are just practice for when I blow up the plans...

[cliffm]

Soooo, what size is the old air knocker gona be?

[BillParker]

I think it would be pretty kewl looking at 72" (that's 300%... Maybe 400%) 96"?

6 foot is considerably easier to handle than 8...

hummmm... You know what? I think we need to do this one....