Brief:
This is a neat display of the interior of a model rocket motor, and at 3:1 upscale, it's large enough to use in a typical classroom presentation.

Construction:
This kit comes packed in a typical rocket baggie with color header card and contains the following parts:

• BT-70 tube
• Laser-cut cardboard detail sheet

This is described as a skill level 2 kit, and I'd say that's accurate. It might not look that tough, but this is actually a pretty detailed and highly engineered kit and requires careful construction skills. The instructions feature excellent illustrations and detailed steps. You will definitely want to pay close attention to them, as this is not at all an obvious/intuitive construction project.

Construction starts out with the assembly of the interior ribs and spine. At first glance, this looks like overkill--this really doesn't need the structural support--but it's intended to reflect the motor casing thickness. Everything was pre-notched and fit very well, and it was quickly tacked together using white glue.

With the guts done, the next phase is tube cutting. The outer section of the model is a BT-70, which needs to be split open almost in half, then trimmed to length. With such laser cut precision details, I'm not sure why the tube wouldn't already be cut to length, but that's minor extra work so not a big deal. This half BT-70 holds the rib/spine assembly, which in turn holds a split open BT-60 section. The propellant section goes into the split open BT-60.

Depending on whether you want to model a booster motor or one with a delay charge, you can choose to build an upper section for the delay. This module is much like the propellant module--a flat piece mounted to a couple semicircles, though in this case it sits inside a TC-60 coupler section to strengthen it a bit.

All told, this can be built in about 2 hours.

Finishing:
Right out of the bag, it looks motor shaped but does not include anything for finishing. You are left to either paint/decorate it on your own, or better yet download the free patterns to print out on white label stock. The patterns cover an outer wrap to make it look like a B6-4 or B6-0 motor plus interior labels to go over the flat pieces identifying the propellant, delay, ejection charge, etc.

I printed off a set of labels, and they looked pretty good, though the outer wrap can be a little tricky to apply and keep perfectly aligned. In my case, I have a very slight wrinkle where I tried to peel it back up to reposition.

I then circled back and hand painted in some of the interior sections, such as the half-cones and the ends.

I coated everything when done with two light applications of Krylon clear acrylic fixative.

Construction Rating: 4 out of 5

Summary:
I think this is a good instructional aid. At $9, it's not too expensive and it's rugged enough to survive being handed around for a show and tell session.

PROs: Very realistic looking.

CONs: Slightly over-engineered. The BT-60 could be supported by just a pair of half rings, no need for the spine assembly.

Overall Rating: 4 out of 5