Brief:
2BZ is an exact 1.67 x scale-up of the Custom Rockets Razor tube fin, except that it flies on a cluster of three C6-7s. The model was an effort to build a "quickie" rocket using only standard Estes tubing -- no wood fins, no centering rings: just tubes and glue.

Construction:
The Components:
(2) 18" BT60 tubes, one cut into 6 x 3" segments, other to 15"
(1) 18" BT20 tube cut into 3 x 6" segments
(1) BT60-sized Estes cone, 14" LOC chute

The Assembly Sequence: 1. I use 5 minute epoxy throughout, white glue optional 2. epoxy left, right tube fins to body tube, let set 3. epoxy 2 additional tube fins to the side, let set 4. turn assembly over, epoxy on remaining 2 tube fins 5. epoxy the 3 motor tubes to one another, let set (Estes-type motor stop rings and motor hooks can be attached if desired, in tube valleys only) 6. block the small empty spaces between the aft ends of the body and motor tubes with a little loose cotton mixed with epoxy or glue, to insure hull pressurization by ejection charges (see photo) 7. add soda straw lug 2" above tube fins, aligned with a portal between 2 tube fins (room for launch wire) 8. recovery system is 14" LOC chute on 7' of para cord

Flight:
"2BZ" is short for "tube easy," or maybe, "too busy". I have only used C6-7s on this ship, which I designed partly with the NARTREK Silver requirement in mind, since there are few cluster kits around. Our club has a nifty 12v multiple launch rack with continuity check for all 7 pads, so (being too lazy to whip together a triple launch clip gizmo) I just wait for a slow period and hog 3 adjacent pads at once so I can insure proper ignition of all 3 motors. This works great, and "2BZ" lifts off on a majestic column of white Estes smoke to 800-900' or so. It tracks straight even in brisk winds. You get an E18-7 boost "the hard way", short a few N-sec, but at slightly lower cost. I know of no easier or cheaper way to put together a decent-sized great-performing cluster ship.

Summary:
With the advent of E and F high power loads, there is little need for clustering little Estes motors anymore. But its fun and affordable, and you need to do this for NARTREK's Silver requirement. The Custom Rockets Razor is a fine tube-fin design, except that its so small that I instantly lose sight of it after launch. This size is more visible and much easier to track. Tube fin designs have well known pluses and minuses. I like the fast, self-jigging build and the superb resistance to weather-cocking, even in a brisk wind.

Other:
Like all the kits I build, scratch designed, plans or kit, I prefer to anchor my recovery system through-the-hull via an external knot an inch below the cone bottom covered with epoxy and half a sawn BIC pen cap. I've never had one of these fail, foul or zipper.