Fusion SpaceMuster

Motor-hardware compatibility for high-power rocketry

J712-LB

752 N·s · 641 N avg

Loki Research · class J · Loki Blue · delay 7, 9, 12, 15 s · built for the 38/740 case

406 mm long · 752 g loaded · 372 g propellant

TRA certified
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Muster is a shopping aid, not an assembly guide. Build only to the reload's printed instructions — always the authority — and confirm every part with the manufacturer before you buy or fly.

What you need to fly it

The simplest build — in its own 38/740 case. Reusable hardware you buy once, plus the single-use reload.

Reusable hardware to own

Single-use reload to buy

J712-LB reload kit

Single-use: liner, propellant grains, o-rings, and the delay or smoke element (the nozzle and closures are reusable, not in the reload), and ejection charge

Source: thrustcurve.org

  • Loki's graphite nozzle is reusable and sold by throat number — the correct throat for this reload is in its instructions, and the wrong one can cause a failure.
  • A dab of high-temperature o-ring grease is needed on assembly (it comes with most hardware sets).

Cases that fly it

Its own case is the simplest; a longer case flies it too, with the adapter and spacers.