Estes Gryplon boost glider build

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Sooner Boomer

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I read the instructions thoroughly before I started. I looked over the parts, too, to get an idea of where they go. Problems, in a bit.
First, unbagging;

bagfront.jpg

bagback.jpg

contents.jpg

balsa.jpg

parts.jpg
 
The glider is a semi-delta with a forward canard wing. It's carried by a 14mm powered booster that attaches via a single "guarded" hook. Except for body and nosecone, all parts are balsa. The wood seemed very hard and heavy. I guess that's a good thing for a beginner glider. If I rebuild or upscale, I might choose a lighter grade of balsa. Most of the laser cut pieces came free of the backer. One piece should have been made from two pieces because of grain direction. A set of pieces that should have been identical are not.

These go on either side of the glider body so the booster has a place to hook on. They should be identical, they're not. The instruction diagram shows them to be the same. I don't know why they're not. Hope it doesn't nake a difference.
part1.jpg

The instructions say to glue everything up on a board covered with wax paper. I used a nylon cutting board. Yellow/white glue don't stick to it. Sorry about focus.

wings.jpg

Gluing the above mentioned pieces to the fuselage.
fuselage.jpg

These are the parts that make up the hook that goes on the rocket booster. Look at the grain direction on the piece sticking out on the bottom piece. It broke in three pieces trying to get it out of the backing. Should have made it from two pieces, but the part that sticks out is a spacer, not structural.

hook1.jpg

The two bottom parts form the hook that carries the glider, the curved tips should match up. Instructions were a bit vague, but I figured it out.
hook2.jpg

This is all three pieces glued together. The part that sticks out is where the launch lug will go.
hook3.jpg

Everything is now glued to the fuselage. The thing under the right-hand side of the canard is a tool to make sure the fins/wings are square and level.

glider.jpg

I glued the nosecone together, tied on the shock cord, and made/installed the other end of the shock cord into the trifold mount inside the tiny, tiny body. (sorry, no pics)

That's it for this evening. Tomorrow, trimming the glider, gluing the hook and launch lug onto the body, and consideration of paint and color.
 
My son and I just built one we put the nose piece with the deeper cut out on the port side of the glider. I don't remember how/why we came to that conclusion though.
 
That asymmetry is odd, but I ignored it. My part with the larger notch is on the right side, but the pod is perfectly secure and separates easily with a tiny backward touch.
 
Tuesday was wasted. I went to wound care, came home, and took a nap. Woke up about 1:00 in the morning. The cat was not happy he had not been fed.

So today, I thought I'd try balancing the glider. There is a through hole laser cut at the balance point for use with an unbent paper clip. Wow! The glider is *extremely* nose heavy! Up there ^ I made the comment about how heavy the balsa is in this kit. This is what happens. I used most of the lump of clay trying to get it to balance. That ain't gonna work. Later today, I'm taking it out to the belt sander in the garage. I'll carefully sand off (and round over) the hook assembly on the nose. It's squared and as aerodynamic as a brick. A lot can be removed (carefully, carefully, checking balance!) without affecting the strength.

Paint: Paint is always an issue with gliders. Paint can add a bunch of weight, and can even affect balance. My thought is to go with two methods. The first is the old method of using magic markers. I'm going to lay down several black stripes this way. Next, I'm going to try some shellac tinted with food coloring (red). The food coloring alone is water-based, and might raise the grain, or warp the balsa. Hopefully neither will be a problem with the alcohol-based shellac. Don't know what the booster will get painted. Red/black sounds like a good combo.
 
Ours doesn't balance at that point and test glided fine. Give it a toss before surgery.
 
Worked on trimming the glider. re-shaped nose quite a bit with belt sander and carving knife. Now more rounded and aerodynamic. Still nose heavy. The supplied clay stayed on just long enough to give it a gentle toss then fell off as I released glider. I made a couple on "U" shaped pieces of solder, and when balanced, superglued them in place. Raining, so I could only test in living room.
 
This thing is giving me fits, trying to get it trimmed! I think I'll see about painting it, then putting it up for a bit until I'm motivated to do tedious, fiddly stuff again. I's going to be at least a month before I can fly it anyway.
 
So today, I thought I'd try balancing the glider. There is a through hole laser cut at the balance point for use with an unbent paper clip. Wow! The glider is *extremely* nose heavy! Up there ^ I made the comment about how heavy the balsa is in this kit. This is what happens. I used most of the lump of clay trying to get it to balance. That ain't gonna work.

That is very discouraging . . . Perhaps you could contact Estes and explain the problem. They might replace the kit.

Dave F.
 
I usually have problems with one wing being heavier. Not really as much of a problem as having a too heavy nose or tail tho. That can be frustrating.
 
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