Strengthening Paper Model Rockets

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By Clive Davis

I thought I would share how I strengthen paper model rockets. While paper rockets are cool, they are prone to damage due to transport, flights, and landings. The following tips should help you get a little more mileage out of your paper rockets.

I have selected for my paper rocket the Regulus, which is available from Eric Truax's site: (http://www.dpileggispicks.com/highflyingcards/)

The Regulus was apparently the US Navy's first nuclear armed cruise missile, and was actively tested from 1955-1966.((Here is another site with info about the Regulus: (http://www.wa3key.com/regulus.html

Step One:

I cut out all the parts to the rocket. This is the most time consuming and tedious process to paper modeling. (Here's a photo:

Step Two: Forming the Parts

Next, I form the parts of the kit. Generally, this means rolling the nose cones and body tubes as well as fin/wing construction. (Once the rocket is formed, I can piece the parts together to figure out how I am going to fit a motor in the rocket. I measured a BT-20 to fit inside, and made sure this was cut to the correct size. Next, I used some of that foam-board that you can get at Michael's. I traced some centering rings to go between the BT-20 and the inner diameter of the main body tube. In this photo, you can see the cut centering rings. (As a means of strengthening paper rockets, this is a way to strengthen them internally. The foam board is very strong, but very light weight as well.

Next step includes the construction of the motor mount with the centering rings glued into place.

Step 3:

Next up, I put the main body tube, motor mount and lower boat tail together. (At this point, you may have wondering why I inverted the nose cone. Partly, I did this for looks as I like the pointed nose, and second, I also wanted a rocket that was slightly more aerodynamic than something with a ram scoop type of nose in the front. Hey, it's my rocket. I can do what I want.

A side note

When putting together paper rockets, there are always those pesky white lines that appear when you merge or glue parts together. One of the tricks in the trade is to use a black pencil or pen to darken the edges of each part. In this project, I used a black Sharpie and a navy blue felt tip pen. (This step does nothing to strengthen the rocket. It just makes it prettier.

Here is a picture of the completed rocket. Before I add strength externally, I want to seal the rocket with a clear coat of acrylic so that the ink doesn't run. The Regulus here has been airbrushed with Future Floor Polish is now awaiting the final step in the strengthening process. (Here are steps you don't see in photos: (1.) I put yellow glue inside the nose cone to add strength. I had two coats(2.) I wrapped cellophane around clay and placed it in the nose cone. The cellophane will keep the moisture of the clay from leaching through the paper to discolor the nose cone. * I learned this through past experiences with clay and paper nose cones.(3.) I cut out a bulkhead out of foam board and glued this at the bottom of the nose cone, keeping the clay weight inside the nose cone.(4.) There is a part of an 18 mm motor cut and glued to the nose cone that acts as a shoulder for mating the nose cone to the rest of the rocket.

Step 4: the Mod Podge

After the clear coat is dry, I put on three or four coats of Mod Podge. I used to brush on the Mod Podge, but this leaves ugly "paint streaks" and the surface is not smooth but has ridges on it. (I then began experimenting with airbrushing Mod Podge to great success. To prepare for airbrushing, I use a small amount of Mod Podge - usually about a Tablespoon.

As you can see from this photo, Mod Podge is fairly goopy, which is not conducive to airbrushing.

I add a small amount of water, bit by bit, until I can thin the Mod Podge down a bit.

The consistency I am looking for is something like heavy cream. It should be thin enough for the airbrush, but thick enough to stick on the rocket and not run all over the place. (In this photo, I have dipped my finger in the prepared Mod Podge. As you can see, it really isn't running, but it is a thin consistency. (Next up: Airbrushing the Regulus.

Here is the Regulus now after two coats of airbrushed Mod Podge. The fins are now stiffer and the body tube is more dense. (I usually add another 2 coats or so to really toughen up the rocket for durability, shape during flight, and landings.

Here is another paper rocket of mine (a Model Minutes kit) on which I painted Mod Podge using one of those foam brushes. While the Mod Podge works the same way, it does leave behind undesirable streaks.

Summary:

So, here are my tips in a nutshell for strengthening paper models:

• (1.) Use internal centering rings and foam board to add strength
• (2.) Coat the inside of the rocket with glue (as I did my nose cone)
• (3.) Coat the rocket using something like Mod Podge (I prefer airbrushing it). Also, I coat the rocket first with an acrylic clear coat so that the ink does not run when I apply the Mod Podge. I usually try to put on 3 or 4 coats.
• (4.) Last, but not least, you can bulk up your fins by placing additional card stock or balsa in the fins. This only works if the fins have space internally for the added card stock. The Regulus is a good candidate for added additional card stock since the fins (all four) fold over onto themselves.

GUEST's OPINION:
"" (X.X.)