(04/15/03) My second "paper build" from one of the free rockets downloaded from Internet was the Model Minutes Tricarrow (See my "Free" Paper-Rocket Comparison Page). This one has two PDF's to downloaded and print. I printed it on 110lb Card Stock (Georgia Pacific brand purchased from WalMart). The instructions are not downloadable and are only on the web. They also do not appear to be finished as the "Balancing" and "Preparation for Takeoff" do not have any information. But, moving on . . .

The rocket patterns were all contained on two pages, one was the body tube and nose cone and the other was the fins. On the first page there was a colored and non-color pattern for the body tube and nose cone.

You will need to provide a recovery system. The instructions show a parachute, but I went with a streamer. You will also need clay nose weight and a piece of 1/4" foam board. Interestingly, you will also need to provide a launch lug (I think they should have provided a template for one)

Model Minutes recommends using a transparent wood glue for assembly.

CONSTRUCTION:

A few highlights of the building process are below. There are a few unique characteristics about this rocket (when compared to other paper-only rockets) that include the hexagonal shape, the nose cone and the fins.

The nose cone is probably the hardest item to build. It is hexagonal in shape and has a cap that needs to be cut around carefully. The hexagonal shape makes it fairly easy to form a symmetrical cone. Once shaped and before gluing the cap over, the nose cone is filled with modeling clay. The instructions say 'oil based'. I used Plast-i-Clay Modeling Clay that I purchased from Ben-Franklins. This has to be done carefully so that the nose cone does not become deformed.

After the clay is in, the cap is glued in place. Then using a template, you are to cut out a nose cone shoulder from a 1/4" thick piece of foam board. This is then glued onto the cap. Lastly you add a eye-screw that is long enough to screw through the 1/4" foam board and into the clay.

The fins can be finished two ways. The simple way is to cut out the pattern and glue them together. They are simply a doubling over of the paper and then where they attach to the body tube and folded outward. The second way is to cut out the fins and also to cut out the center section. Then a piece of transparent colored film is placed into the fin when it is doubled over. Model Minutes suggest letting the fins dry in a book to help keep them flat.

The body tube is also hexagonal and so a light scribe on the lines helps you achieve a symmetrical shape. The body tube has a glue tab that is used to make the seam. This makes the seam raised a bit.

The instructions tell you to make a thrust ring from paper (did not provide a pattern). They also tell you to make a launch lug from paper (did not provide a pattern) or to use a straw.

For the recovery system, I used 32 inches of 1/32" Kevlar® for my shock cord. It was attached using the 3-fold paper method (a pattern was provided) to the body tube. It was tied to the eye-screw.

I added a 24" x 3/4" Nomex® Streamer. I cut this from a roll of Nomex® that I had purchased from the now defunct Rogue Aerospace many years ago.

Overall, for CONSTRUCTION I would rate this rocket 2 ½ points. Even though it is a "free" rocket, the online instructions suffered from incompleteness and language translation. Now on the other hand, the pictures were great! You can see some of them throughout the review. In addition, I believe the hexagonal shape is a great way to start with "paper building" techniques.

FLIGHT/RECOVERY:

Model Minutes did not indicate an expected weight or recommended motors. My rocket weighed in a about 0.6 ounces.

My first flight was on an A8-3. The motor is friction fit into the motor mount until it hits the thrust ring. I added a couple of balls of wadding and rolled the streamer. Everything was ready.

The flight was impressive as I was surprised at how stable and straight it flew. I actually expected trouble because my doubled-over fins were not a perfectly flat as one would hope. But the large fins certainly makes the rocket stable. Ejection on the A8-3 was early since it was still clearly heading upward.

The second flight was on a B6-4. Again straight off the pad. Just when thrust stopped something happened. A fin tore from the rocket and it flipped and flopped in the tracking smoke until ejection and then fell to the ground. Interestingly the fin did not tear at the joint, rather, it tore from about 1/2" out from the body and down. Not what I would expect.

Thought of repair never entered my head, so I salvaged the recovery system and threw away the rocket.

For FLIGHT/RECOVERY, I would rate this rocket 4 points. I'm struggling with the rating on this because the Tricarrow flies very well. It is super stable and flies straight as an arrow. Of coarse the second flight broke apart. I'm giving it a 4 to recognize that failed flight, but wonder if it was because my fins were not so straight (see picture above - look close) and that put too much stress on them or what?

I give the rocket an OVERALL rating of 3 points. As a "free" rocket it provides a bit of unique fun having to build it from paper. The instructions are marginal, but again with the pictures it can be understood. The flights appear to be great . . . not mine, but I'm sure I'm the exception. The nose cone is excellent, with the foam board shoulder and eye-screw. All-in-all an average. Might try building this one again with the see-through fins.

(Contributed - by Daniel Kirk - 03/28/06)

Brief:
This rocket is a free download in .PDF format. You just have to print on cardstock and build. (Some additional parts required.)

Construction:
This rocket prints on two pages. It has a hexagonal body tube and nose. Its 3 fins are cut from two layers of cardstock and glued together. Fins include attachment tabs that make it easier to glue them to the body tube. The directions recommend 110 lb cardstock. I've built several paper rockets in the last couple of years, and have always found 67 lb Bristol Board entirely adequate. User supplies several other parts. (See list below.)

Instructions were simple and straightforward. I had no trouble understanding or following them. I have built Fliskits' Caution Rocket, Midnight Express, and Nebula, and all of Art Applewhite's free paper rockets, and found the Tricarrow among of the simplest paper rockets to build.

Model Minutes suggests the following supplies:

• Use a transparent glue. Mod Podge Paper with a small brush works well.
• Non-Drying Modeler's Clay
• Small square of 1/4" Foamboard
• Small eye-screw with 1/2" long threads
• Small plastic bag (or left over 8" plastic parachute)
• 60" Thin string
• 12-18" rubber band or 1/8" elastic
• 1" length of a drinking straw, at least 1/8" in diameter

I made a few substitutions:

• Elmer's Washable School Glue No-Run Gel, which I use on all my paper rockets now. It wrinkles the paper less than anything else I've tried.
• 5 minute Epoxy for nose weight.
• I used a Semroc chute I had lying around. It was larger than 8", which was my downfall.
• 5 feet of 3/8" polyester ribbon for a shock cord.

I had to run to the hardware store for a screw eye. Most rockets used them when nose cones were made of balsa, but it's just not something I keep on hand anymore.

I scored the dotted fold lines with the back of the blade in my hobby knife and using a steel ruler as a straightedge. Folding the hexagonal tube and nose was easier than rolling the cylinders and cones of other rockets. I found it worked best to spread the glue with a flat toothpick like butter with a butter knife then wipe off the excess with my finger.

After folding the nose, I filled it with 5-minute epoxy for nose weight. Be sure to coat it thoroughly using two coats of glue if needed or the epoxy may soak through just enough to discolor the outside. I cut the foamboard carefully, but I still had to sand it down to fit the tube--a tradition that continues from the days of balsa.

I elected to skip the clear plastic fin cutouts. Like the earlier reviewer, I could not get my fins perfectly flat. The glue tabs, however, made attaching the fins the easiest of any paper rocket I have built so far, and combined with the hexagonal tube, the fins were self-jigging so they went on perfectly straight.

The PDF now includes an engine block and a launch lug, although you have to provide a drinking straw as a form to roll the lug--why not just CA the straw to the rocket? I used the full length of the lug pattern, but I thought it was a little thick, more than twice the thickness of the body tube.

Instructions for balancing have been added: "Always perform a swing test on your Tricarrow prior to flying for the first time with a B4-4 loaded. " There are no instructions for prepping the rocket. Not that any explanation is needed if you've ever built a rocket before and this is just your first paper rocket.

The problems in the instructions have been fixed and this is a good introduction to paper rockets. The only thing I didn't like about the construction was that it required more user supplied parts than most paper models.

Finishing:
There is no finishing needed, but there is a blank pattern if you want to choose your own colors and the unusual transparent plastic fin insert option for those who want more customization.

Construction Rating: 4 ½ out of 5

Flight:
The recommended motors are A8-3 and B4-4 only. "Larger thrust motors are not recommended." I noticed in the flight logs that the bad flights were on higher thrust motors, so I bought a pack of B4-4s, which is a motor I don't usually keep on hand.

Boost was straight with no weathercocking, but enough spin to leave a clear corkscrew in the smoke trail, possibly from the fins' slight warp.

Recovery:
Ejection was at the top of the arc with the nose horizontal. I had packed the chute too tightly, so the ejection blew a hole in the side of the body tube and the rocket came in ballistic. There was some mud on the nose but no further damage beyond the hole in the side.

I give the rocket 5 flight points. It did what it was supposed to. The damage was my fault for using too large a chute and not checking to see that it would eject freely.

Flight Rating: 5 out of 5

Summary:
Not everything is done the way I would do it, but it is an easy build, a good flyer, and a good introduction to paper rockets.

Overall Rating: 5 out of 5

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

SPECIFIC ROCKET TIP:
06/03 - "I agree with the tip about scribing the fold lines with a pen, butter knife, etc, (I use the fingernail file blade of a miniature Swiss Army Knife). Also, for short fold lines, I just lay the line against one blade of the scissors I am using and press the back side to make a crease along the line. It's quick and I already have the scissors in my hand." (W.H.J. )

SPECIFIC ROCKET TIP:
04/03 - "Great reviews! An old trick from my model railroading days is to 'scribe' fold lines in cardstock from the back with a ballpoint pen and straightedge. This will cause the card to roll a little bit in the right direction to start. You can put the pen in the freezer for a few minutes to keep the ink from flowing while you do the scribing." (R.T.P. )