Monday, May 28, 2018

Apogee Payload Altitude Rocket Build, Part 7, Pop Launch Lug

I'm going old school, I hope pop lugs are still allowed in competition! I hope to find out find out before going to NARAM.
In the comments below, let me know if they are still used in contest flying.

These instructions are from the OOP CMR V.I.P. kit
Two different wire bends are made.
The upper bent wire goes into a small hole in the body tube.
The bottom wire is bent into a rounded "W" and is held on by going around the fins.
Both wires are taped (or card stock strips are glued) around a launch lug. According to the CMR catalog, the launch lug is  around 5" long.

The pop lug is fitted on the rocket at the launcher. A wrap or two of tape goes onto the top of the launch rod. At ignition, the rocket slides up to the top of the launch rod. The top of the pop lug hits the tape wrap and is left on the rod. The rocket continues on its flight without a launch lug.

I'll be using one of the altimeter vent holes for the top bent wire insertion. The upper bend will be a doubled over wire as opposed to the single end.

The first bend is easy enough, near the center of the wire.

TIPS: The tape strip is to direct the next bends. I found it very hard to get the "mirrored" bends accurate. Setting small tape strips at the bend points lets you set the pliers at the same place on both sides.

On the left is the two outward bends. That first tape strip is removed.

Two more small strips of tape set up the next bends.

The bottom is bent round and the width of the half circle sets the wire end tight to the side of the down wire on the right.
More in the next post . . .


  1. I've never entered a NARAM competition, so this is just my opinion. In looking at the U.S. Model Rocket Sporting Code (rule book for NAR competition) it says under Sec. 5:

    5.4 Launching Device A launching device or mechanism must be used that restricts the entry in its pitch axis until sufficient flight velocity is attained for safe, predictable flight. Recommended launching devices are a steel launch rod, tower, rail, or piston.

    So if towers, piston launchers, and fly away rails are acceptable, I would think a pop lug using a rod would be also. All eliminate the drag of a permanently attached lug. But email the NAR for a definitive answer. Maybe the Regional Contest Director for the West (Colorado).

    1. Hi BAR,
      Thanks, I may write an email.
      I also have some fly-away guides so all bases will be covered.

  2. P.S. I see that there are Craftsmanship events. Are you entering one of those? Seems like that is right up your alley!

  3. Hi BAR,
    If I have the time, I might enter one of those events. No scale though!