I don't have the origami scale plan handy, but I just threw a ruler across the bottom of my Hummer BT50. Those are 2-3/16" along the root edge.

Original scale. Darn auto miscorrect.

Here are the BT-60 upscaled parts.

Attached Files

	BT 60 upscale p1.pdf (258.4 KB, 56 views)
	BT 60 upscale p2.pdf (262.3 KB, 45 views)
	BT 60 upscale p3.pdf (280.2 KB, 51 views)

__________________
Greg Poehlein

Member of Launch Crue - http://launchcrue.org/

Hint #1: Do not use magician's flash paper for recovery wadding!

Hint #2: Clean your shoes after flyin' in that cow pasture - that ain't no dirt clod on the sole!

Got to fly my BT60 Upscale today. Short, but nice flight.


http://www.youtube.com/watch?v=O7ccLhaf4PA

Edited to a higher resolution upload.

This upscale is using an ejectable motor pod with two washers epoxied ahead of where a stream wraps about the engine mount tube. The rear centering ring is cut oblong, so I can wedge the engine mount to be axial, or off axis. This flight was on-axis.

The wings are cut from foam core with the top layer of paper soaked off. I sanded an airfoil in, and then glued the printed paper pattern over the foam. The tail is a flat plate, but mounted with a very small angle to give it some 'up' elevator.

The launch site is an orchard just north of Bong in Brighton, WI.

I loose track of it with the camera, but at the end of the flight, the Hummer stalls when it turns into the wind, and pulls out just above the grass.

Charles

Nice flight...

What engine did you use?

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Dreaming of making the rockets I dreamed of as a kid (and then some).

"The Guide says there is an art to flying", said Ford, "or rather a knack."
"The knack lies in learning how to throw yourself at the ground and miss."

Launching is Optional... Landing? That Depends on Trees.

B6-2

The other mods for this scale that I recall right now:
The launch lug is mounted on the top of the body tube. My thought was to 'hang' the model from a slightly angled launch rod.
The side tubes, which are long launch lugs in the original, are McD's straws.

Charles

I kept trying to print the .pdf's (turning off "fit to page", etc), and the parts don't match up. The tail and booms seem to be a lot larger than the wings.

One thing that would help me quite a bit is if each page had a "scale inch" so if my school/Kinko's printer changes the dimensions, I can check against this inch, and rescale it in a photocopy.

__________________
.
.

Dreaming of making the rockets I dreamed of as a kid (and then some).

"The Guide says there is an art to flying", said Ford, "or rather a knack."
"The knack lies in learning how to throw yourself at the ground and miss."

Launching is Optional... Landing? That Depends on Trees.

On my files, or Greg's?

And the tail does seem huge. Or rather, the wings are pretty small on this model - all the versions I've built. Have you tried printing out the pattern, cutting out the parts and just taping (or loosely fitting) them together? With the root edges butted together and the booms fit onto the tail, the booms should line up with the little notches on the wings. Which is also where the bottom cheveron-like piece ends up - just inside those notches.

When I switched from a flat sheet to an airfoil on the wings I ended up tilting the booms inward to match the dihedral. On the smaller scale Hummingbirds with flat lift plates, you can keep the boomns square to the tail.

Charles

Here's how the pieces of Greg's BT60 upscale files fit together for me. I laid the booms flat and traced the notch on the wing so you could see it. There's a quarter sitting in one of the tail stars.

And to answer an earlier question, the root edge of the wings in the pic are 92.4mm.

Attached Thumbnails

 

I don't know, and unfortunately am not at a computer w/a printer to re-print and test. I don't know when I'll be able to try again to find out, as I've got a busy day scheduled... 7am until 9pm, I'll be doing school "stuff" or commuting by bus.

__________________
.
.

Dreaming of making the rockets I dreamed of as a kid (and then some).

"The Guide says there is an art to flying", said Ford, "or rather a knack."
"The knack lies in learning how to throw yourself at the ground and miss."

Launching is Optional... Landing? That Depends on Trees.