Card Stock Pterosaur X

Hi there. This is a flying model made out of card stock, chipboard, a piece of balsa wood, and glue. The plans are quite detailed and there are lots of images for reference. Expect to spend three hours or more building it.

Although I had made a design similar to this one, I started digging a little deeper into pterosaurs and was fascinated by some of the more recent (last 10 or 20 years) interpretations, particularly with regard to wing shape. This one doesn't have pointy wingtips like the last one, and the average chord is shorter. The video for the last one (Card Stock Pterosaur) might be a useful reference if you were to get stuck or confused during the building process.

Supplies

1. balsa wood (1/8" thick x 1/4" wide x 8 cm long)

2. two sheets of card stock, 8.5" x 11", preferably 65 lb. and 80 lb.

3. chipboard, preferably 0.8 mm (1/32"); if you don't have anything this heavy, try gluing together layers of thinner material and allowing it to dry before cutting

4. glue

5. scissors

6. access to a printer or photocopier that can handle card stock

Step 1: Download and Print

The document consists of four pages. Page one has instructions and stencils for the chipboard pieces. Two and three are for the card stock. Four is a reference drawing.

Step 2: Cut Out the Shapes and Build the Main Components

The piece of balsa wood you will cut out is the foundation of the whole design. (At left in the photo is a spare piece of balsa, not to be confusing.)

To it you will attach the main wing/body, the wing spars, and the long neck pieces. The body/wing gets some extra bracing (chipboard) and a top layer (darker green). The neck pieces extend forward beyond the balsa so they can hold the head in place.

Here are two mistakes you will want to avoid.

(1) Gluing the balsa wood as far back as the legs. No! Use the reference lines that are on the top of the main wing/body.

(2) Allowing the pieces to drift as the glue dries. No! The neck really needs to be perpendicular to the wingspan, and it needs to be right on the center line.

Step 3: Cut Out the Shapes and Build the Rest

Now the tedious stuff. There are a lot of weirdly shaped pieces that will cover up the body and head. Work from the aft end toward the nose so the coverings will overlap correctly (front ones over the back ones, a few millimeters).

The placement of the canard airfoil is pretty important. Make sure it is not sloping down too much. If it is, the pterosaur will tend to pitch down. You can use a little bit of chipboard under the front of the airfoil to raise it. You can also bed down the elevators of the airfoil to create more lift and, thus, cause the thing to pitch up a bit.

Step 4: Test Fly and Make Adjustments

Hooray! You made an awesome flying model based on an extinct species of a flying reptile.

Now, here are three mistakes you will want to avoid.

(1) Flying the Pterosaur before the glue has cured. No! The glue isn't strong when it's wet. Also, the weight of the glue changes as it dries, and you won't get an accurate idea of the balance of the plane if you fly it too soon.

(2) Getting frustrated because the plane doesn't fly well. No! It can do some cool stuff, as seen in the video. Check the CG. If the plane is tail heavy it will usually veer off to one side and dive into the ground. Add pieces of card stock, or devise some other method of adding weight to the nose, if that is happening. Also, you need to sight down the nose and make sure the wings are symmetrical. You can correct twists and problems by gently and repeatedly shaping the material with your fingers. Lastly, learn a little about basic aerodynamics, if you haven't already. If you want pitch up, curve the legs up and/or bend the canard elevators down.

(3) Flying the pterosaur when it is windy or wet. No! You'll have a lot more fun, and your work will last longer, if you fly when the conditions are right.

Comments

[Miguelv13]

You can make one that simulates the flapping of a bird. I saw a paper plane that does that. Half of the wings were softer at the tips.

[Cohesive Contrivances]

Been wondering about building something like this for a while, so I'm glad to have found your delightfully artful example and plans to go by! After I try making a practice one with plain paper, I've got some shimmery blue Japanese paper that'll make for really nice-looking "skin" on a second one.
Very clever to use a canard. I think it beats alternatives for nose-up lifting surfaces, such as webbed feet angled awkwardly upward at the back, or stretching the trailing edge of the wing further back with an upward twist.
Also been puzzling over how the heck a real pterosaur with a big head on a long neck—and therefore a more forward center of gravity?—managed to balance out in a glide, rather than just nose-diving. There has to be some nose-up lift somewhere. According to this paper, it may be a combination of forward sweep of crescent-shaped wing tips as well as upward tilt of the trailing edge in the middle of the wing. https://europepmc.org/article/PMC/3267140 So maybe pterosaurs really did glide with their ankles hoisted goofily toward the heavens!

[zdedesigns]

Thanks. Glad you like it. I agree that a shimmery paper would look fantastic! ... I also have wondered if a quetzalcoatlus or pterosaur of similar shape was able to fly, and for the same reasons you mention. The brain and beak have to account for a lot of weight. If you look at a flamingo in flight, they stick their long legs straight back for counterbalance. Anyways, I'll leave it to the paleo scientists to figure it out. I think the forward sweep is the best explanation I've heard. And if I ever get ant aft-wing glider to fly reliably without a canard, I'll be sure to post.

[mischock.0306]

Hello, mister! I`m trying to biuld this project and i`ve stuck with a little misunderstanding the drawings. the drawing i see on the picture (jpg) differs to the one i download from the link (pdf). and i dont understand the right place to glue a piece pf balsa to. can you please make a little explanation to this? Thank you.

[zdedesigns]

Good question. If you look at letter B on pg. 2 of the plans, you can see a rectangle at the center of the wing/body. That is the outline of where the piece of balsa should be glued. The balsa is glued on the bottom of the wing, but since the plans aren't for double-sided printing, I had to put the outline on the top of the wing. ... I hope this answers your question.

[Eric Caruyer]

Nice traveling !

[zdedesigns]

Cheers!