DynaStar Rip-Roar

DynaStar - Rip-Roar {Kit}

Contributed by Chan Stevens

Construction Rating: starstarstarstarstar
Flight Rating: starstarstarstarstar_border
Overall Rating: starstarstarstarstar_border
Diameter: 2.22 inches
Manufacturer: DynaStar
Skill Level: 3
Style: Multi-Stage
Dynastar Rip Roar

Brief:
OK, take one look at the flame decal, the cool paint scheme, and imagine the two-stage flights. Now tell yourself you don't want this kit. This is an easy build, looks great, and flies pretty darned well too.

Construction:
The Dynastar line is a mid-power line offered by Apogee, based mainly on designs by Shrox. This means you'll get good quality parts and a well-designed product although it's a little bit pricey at $37. I happened across one on an auction site and scored it for a much more affordable $25. The parts list includes:

  • 2 24mm motor tubes
  • BT-70x12 upper body
  • BT-70x6 booster body
  • TC-70 coupler
  • 70/24 centering rings (die-cut cardboard)
  • Plastic nose cone
  • Laser-cut balsa fins (1/8")
  • 1/4" launch lug
  • Peel and stick decals
  • 32" plastic chute
  • 300# Kevlar®

This is listed as a skill level 3 kit on a 5 scale, which is slightly overstating it in my opinion. Other than the fact that this is a two-stager, there's nothing especially difficult about the construction, and the directions are clearly written, making construction a breeze.

Construction starts with the booster assembly. The motor mount includes a 24mm tube with a motor hook held in place by a centering ring and a motor block. Another pair of centering rings hold it in place within the BT-70 tube. Bond a coupler and a set of 3 fins and it's good to go.

One tip I'd offer on the booster would be to coat the coupler thoroughly inside and out with thin CA then sand the outside down smooth. This will help insure consistent separation and it should help it hold up over many flights.

The sustainer assembly is about the same as the booster--motor tube with metal hook and block, centering rings, bond into the BT-70, and tack on a set of 3 fins. You'll want to think through whether or not you intend to fly longer E motors though, as the metal hook supplied with the kit is D-sized. This means you'll either have to leave it out or swap it from your spare parts stash. The Kevlar® shock cord is anchored to the motor mount, providing for rugged and durable recovery.

This is the first time I've had a chance to see the new Apogee 70mm nose cone up close, and I was very impressed. It's got scribe lines for cutting off the tip to convert to a boat tail, so it has multiple uses. It's a whopping 5:1 ogive and looks great. It was a bit loose in the 56mm body tube, however, that is easily resolved with a few wraps of masking tape.

Finishing:
Finishing is the real key to this rocket as it's worth the effort for a good paint job. Once you've filled the spirals and balsa grain (bog fins=lots of filler work), lay down a couple coats of gray primer, then lightly wet sand with 400 grit. Next, paint the fins yellow (booster) or orange (sustainer). Once dry and cured, mask off the fins, and paint the body tubes gloss black. The nose cone is supposed to be red, but the top of the flame decal is a pretty wimpy red (almost pink) so stick with a light or cherry red rather than a darker shade.

The decals come in two sections--the Rip-Roar label and the flame graphic. They just barely fit along the length of the rocket, and because they're peel and stick, you don't get multiple chances to reposition so line them up carefully. I applied the Rip Roar as a single label spanning across the assembled booster and sustainer then cut along the joint to separate them.

Finish everything off with a good clear coat and this will be one of the sharpest looking rockets on the field any given day.

Construction Rating: 5 out of 5

Flight:
For the first flight, I went for the full load--D12-0 and E9-6. The booster hauled a bit faster than I had expected given the large fin area, but so far, so good--nice straight boost. As the sustainer lit and I got stage separation, it kicked off at about a 30 degree angle into the wind. While it was quite stable and flew fine, I was hoping for a better flight profile. The angled flight resulted in deployment just pas apogee, though the -6 would normally be fine.

Recovery:
I felt the 32" plastic chute might be a bit overkill, so traded down to go with a 24" spherachute hoping for a shorter walk. I had no problems and would have to say the 32" plastic chute would also be fine.

Flight Rating: 4 out of 5

Summary:
There's lots to like about this rocket--great looks, 2-stage flight, and quality kit. If I had to list a con, I'd wish for a vinyl decal instead of the clear tape stuff and possibly a nylon chute or even mylar over the plastic, although that would push the cost even farther up the scale.

Overall Rating: 4 out of 5

Flights

comment Post a Comment