I started this 10.00 project last winter and lost interest for a while. The box of parts looked sad and dusty so I finished it up. Basically a 29mm/24mm/24mm minimum diameter model. Used a 29 thick wall for S1 and instead of worrying about aerodynamics, just stepped it to 24 with a 29mm - BT50 centering ring and a short piece of BT50.
Plan is F15-0 / E12-0 / and my last good (2/3 successes) E9-8 I have been hoarding. Rocksim predicts 6500-7300' depending on Cd. Max speed of 784 fps. With Estes motors this deserves an LMAO, best part is total impulse (104Ns) and peak thrust make it a mid-power launch. Rocket will be covered with reward and phone number sharpie and I will let a JL Altimeter 2 go ballistic and hope for the best. Would love a pic of the JL2 reading something ridiculous for Estes motors.
Going 29-24 on S1 turned out pretty good - pleased with that. Biggest hurdles are S1 sturdiness (F15 casing is heavy). I used a thick wall 29mmt tube and 1/8" basswood papered fins with glue prime, glue rivets, and paper reinforcing hinges. Went for sturdy vis fluttery fall - this may not turn out well...we'll see. I put the 1/4" lug on S1 so no standoffs required. The motors all overhang quite a bit so she should stay together : )
S2 is nothing special - just a BT50 min dia stage, again with 1/8" basswood fins, papered and reinforced just like S1 to take the landing smack.
S3 is a BT50 with a BMS coupler sleeve up to the payload section as engine block. This may be needed for flight stress (I had an Apogee Aspire that buckled on a spiral) but I really needed a strong cord anchor. The biggest problem with the design is ejection speed - you really need a 10 second delay on the S3 motor. Speed at deployment is over 100 fps and so Kevlar cord tied through the body tube and sleeve along with a lot of elastic. Nylon streamer - they don't do much for fall but are sturdy and visible.
Here's a pic of Long Shot sitting on a nice display stand I built for an HPR, and pics of the S1 build. Should be an entertaining vanishing rocket, super entertaining if I get it back.
Cheers / Robert
Plan is F15-0 / E12-0 / and my last good (2/3 successes) E9-8 I have been hoarding. Rocksim predicts 6500-7300' depending on Cd. Max speed of 784 fps. With Estes motors this deserves an LMAO, best part is total impulse (104Ns) and peak thrust make it a mid-power launch. Rocket will be covered with reward and phone number sharpie and I will let a JL Altimeter 2 go ballistic and hope for the best. Would love a pic of the JL2 reading something ridiculous for Estes motors.
Going 29-24 on S1 turned out pretty good - pleased with that. Biggest hurdles are S1 sturdiness (F15 casing is heavy). I used a thick wall 29mmt tube and 1/8" basswood papered fins with glue prime, glue rivets, and paper reinforcing hinges. Went for sturdy vis fluttery fall - this may not turn out well...we'll see. I put the 1/4" lug on S1 so no standoffs required. The motors all overhang quite a bit so she should stay together : )
S2 is nothing special - just a BT50 min dia stage, again with 1/8" basswood fins, papered and reinforced just like S1 to take the landing smack.
S3 is a BT50 with a BMS coupler sleeve up to the payload section as engine block. This may be needed for flight stress (I had an Apogee Aspire that buckled on a spiral) but I really needed a strong cord anchor. The biggest problem with the design is ejection speed - you really need a 10 second delay on the S3 motor. Speed at deployment is over 100 fps and so Kevlar cord tied through the body tube and sleeve along with a lot of elastic. Nylon streamer - they don't do much for fall but are sturdy and visible.
Here's a pic of Long Shot sitting on a nice display stand I built for an HPR, and pics of the S1 build. Should be an entertaining vanishing rocket, super entertaining if I get it back.
Cheers / Robert