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I want to make some sugar rockets that can use Estes rocket motors as well as the motors I make, does anyone know the dimensions of the motors, specifically the larger and more powerful ones? Fin designs would also be helpful.
EDIT: I have decided on a trapezoidal fin design and an E or F motor
The dimensions and lifting capacity of Estes motors are detailed in the catalogue that you can download from their web site. https://estesrockets.com/catalogs/
I have uploaded some Estes fin designs which you will probably be able to modify for your motors. See my https://www.thingiverse.com/thing:3583502
I will be curious to know how you get on with your project.
Believe me, making KnO3 motors that perform well is harder that it looks. Especially if you want the thrust / lift for your rockets. End burning sugar engines don't perform very well. You need center cored. If you have very light rockets you stand a chance. King of Random has a video on YouTube on dry packed sugars using 3/4" PVC. I have used this a couple of times but were very inefficient. I now pour molds and casings making delays for the chutes with slow burn fuse. The White rocket has an engine mount that unscrews for E and F sizes. The Red Rocket is 3/4" Sugar. I 3D print the nosecones, interstage couples and engine mount parts. The fins and tube constraints are done on my K40 Laser cutter.
The total weight of the rocket excluding the engine is around half a pound and the height around a foot tall, I do plan on experimenting with graphite for the motors to keep the fuel from transferring heat to the casing, (because I have quite a few graphite rods as well as powder that I need to get rid of) and iron oxide in the fuel to increase the thrust and burn rate.
I am planning on coring the motors though, as rockets without cores, as you said, don't perform well because of their burn rates, even a lot of artillery propellant grains have cored centers because without them they burn slowly. I might try some other core shapes as well and see how that turns out
From looking at the motors, I'm probably going to need a motor 29mm in diameter, I've been looking at an aerotech motor as the estes ones won't work well without boosters ( https://www.apogeerockets.com/Rocket_Motors/AeroTech_Motors/29mm_Motors_Single_Use/Aerotech_29mm_EconoJet_Motor_F20W-4 ). I'll need to cut weight by making the rocket smaller or by taking away the section used for holding the estes/aerotech motor if it doesn't have enough thrust. The rocket (excluding motor and parachute) would probably weigh a little over half a pound because I'm basing off my PVC rocket, but I want a more powerful motor just in case I want to change anything. I could add spots for boosters too.