Mini-Max motors being 1.125" in diameter fit Centuri LT-115 tubing. I considered the rocket could have been a true minimum diameter eliminating the need for couplers using the Mini-Max sustainer motor overhang to couple the two stages. This would have saved weight and been a better choice overall considering what the original rocket was designed for.

After noticing the fins on the Centuri Scorpion already offered as one of the Large Scale line of kits designed for these motors, I opted to build mine using SEMROC LT-125 and using the slip fit LT-115 for motor mount/couplers in my model. The Scorpion fins are a dead ringer in the line drawing for the booster.

Wanting to fly my model on readily available 24mm motors, but retaining the 29mm basis from the original design I made 24mm removable motor mounts. Bring on the Quest ThunderJet F motors and I'll throw those 24mm mounts away! You can see a 24mm slip fit mount inserted in what became the LT-115 motor mount in the sustainer in the first picture. With a 1" dowel, you can push the entire assembly from the front, out of the rear of the rocket.

All fins are basswood. Booster fins are standard SEMROC Scorpion kit fins and Scorpion airframe cut down to 8" long with LT-115 tubing running the full length of the booster plus about 1-1/2" to serve as the coupler. The entire model is built using 5 minute Devcon epoxy because that's what I have on hand.

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__________________
Steve Naquin
TRA# 677 L2
NAR# 85518 L2
SAM# 0052

🚀 In Construction: Der Blue Maxx/Minie-Magg 5.5” & Vander-Burn MDRM Clone w/Stickershock23 Custom Decals
🚀 In Paint & Detail: USR Banshee
🚀 In Build Queue: Estes Doorknob w/Vander-Burn Rocketry Upgrade Kit [Sport Decor], Semroc Centurion-F, Semroc Egg Crate
🚀 In Repair: SLS Lil’ Hustler, SLS Aero-Dart 1969 Trim
🚀 Stay Tuned For Fall 2021 Launch Dates