Cardboard Fin Alignment JigAligns three 1/8” thick fins on a BT-50 Tube

P/N 35529

Achieving perfectly aligned fins has never been so easy thanks to this inexpensive fin alignment jig. It is designed to align three 1/8” (3.1mm) thick fins onto a BT-50 size (24mm diameter) body tube. It is great because it holds all the fins at one time, saving you time and frustration.

Schools will love this device, as it greatly sim-plifies the assembly of rockets like the Apogee Avion, or the Estes Alpha™. Straight fins on a rocket add safety, because it helps assure the rocket flies upwards (instead of sideways) which is predictable.

Students will like this assembly jig, because the fins look more professional. People will ask them how they got the fins evenly spaced and so straight on the tube. And the rocket will fly higher and faster into the sky!

The alignment jig is reusable, so it saves you money if your school builds rockets every year!

Required Assembly Materials:

White or wood glueHobby knifeFine grit sandpaper (Approximately 200 grit)Low-tack masking tape

Assembly and Use

The cardboard fin alignment jig should be as-sembled prior to building your rocket, as it will take some time for the glue to dry.

Step 1: Use a hobby knife to cut the tabs hold-ing the parts in the cardboard sheet. Remove the parts and lay them out on your table.

Step 2: Take the spacer pieces, and slide them together to make three “X” shape assemblies. Do not use glue on them.

Step 3: Insert one of the “X” assemblies into the “X” shape cut-out on one of the large triangu-lar plates. Push it in hard so the the tabs extend through the cardboard and protrude out the oppo-site surface.

Step 4: Repeat the process for the other two “X” assemblies. When all three “X” assemblies are in one plate, place the opposite plate on. Again, the tabs should protrude through the outer surface of the triangular plate.

Step 5: Using white glue or wood glue, put a bead of glue on the tabs that extend through the outer surface of the plates. Smear the glue around to work the glue into the crack where the tab pro-trudes through the surface. Repeat the process on the other side of the jig. Allow the glue to com-pletely dry before using it. You only need glue on the outside surfaces, not on the “X” pieces inside.

Using Your Fin Alignment Jig

IMPORTANT: USE ONLY A LITTLE BIT OF GLUE WHEN ATTACHING THE FINS!

Step A: Test fit each fin through the slots on the fin alignment jig. Sand the fins as necessary so they slide easily through the slots.

Step B: Slide the fin alignment jig over the tube. Position it about 1/4” (6mm) from the end of the tube where the fins will be glued.

Step C: Apply a bead of glue to the root edge of the fin. This is way too much glue!

Step D: Using your finger, wipe off nearly all the glue from the surface of the wood. If any dripped on the sides of the fin, wipe that off immediately too.

You only want a thin film of glue on the edge of the fin. Just a little bit of wet shine, with no puddles or globs anywhere on the surface.

Step E: Slide the fin through the slot in the fin alignment jig. Try to keep a gap between the fin and the tube, so that the glue stays on the edge of the fin.

Step F: When the fin is in the correct position on the tube, push down on the tip edge of the fin to mate the fin to the body tube.

At this point, be careful not to rotate the tube in the fixture, as doing so will break the glue bond of the fin with the tube.

Step G: Repeat the process of adding the fins. Allow the glue to dry completely once they are all added. If you only used a thin film of glue, it can be dry in as little as 5 minutes. If you live in a humid environment or if you used too much glue, it will take longer for the glue film to dry.

Step H: To remove the rocket from the fixture, press on the end of the tube to slide the fins out. DO NOT PUSH ON THE FINS!

Step I: Add a bead of glue along the joint be-tween the fin and the body tube for each fin.

Step J: Using your finger, squeegie the excess glue off the rocket. Clean off your finger on a paper towel after every fin joint. Lay the rocket horizon-tally, and allow the glue to dry.

Using the Fin Alignment Jig with thinner fins

1. You can use the fin alignment with fins that are thinner than 1/8” (3mm). But you need to shim the fin to center it up between the slots. Use a low tack masking tape, like painter’s blue tape. Put an equal number of layers of tape on both sides of the fin. Keep the tape away from the root edge of the fin as shown in the photo to the right.

2. Trim off the excess tape, so that the fin easily slides through the slot. Test fit each fin into a slot to make sure it slides easily, but does not wiggle side-to-side.

3. Glue the fins to the tube using the same pro-cedure as before.

4. Use care when removing the tape, as it is easy to snap off a fin. After removing the tape, be sure to apply a fillet of glue to both sides of the fin.

Apogee Components, Inc.3355 Fillmore Ridge HeightsColorado Springs, Colorado 80907 USA

Visit our web site today:www.ApogeeRockets.com

Instruction Sheet P/N 31099