Gunstar
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https://www.printables.com/model/514768-motor-retianers-bt-20-and-bt-50-estes-compatibleZ
These motor retainers are designed to be interchangeable with Estes BT-20 and BT-50 motor retainers, so if you have lost a cap, you can just print a replacement and use that. If you have an extra cap for some reason, you can print a base to pair with it.
The base glues onto the body tube and the cap screws on to keep the model rocket engine in place.
I included a taller version of the cap because I like to glue a thrust ring in the body tube so ¼ inch of the motor sticks out past the end of the base, making it easier to remove. When you do that you need a longer cap.
I would not recommend printing this with PLA due to the heat exposure. PLA+ might work well enough, ABS for sure. No supports are needed. I printed with a .4 nozzle and .2 layer height with the Outer Wall Line Width to .3 For the BT-20 a .2 nozzle might give a smother result but isn't a must.
Thread specs:
BT-20: pitch 1.525mm, base diameter 22.25mm, cap diameter 23.5mm
BT-50: pitch 2.12mm, base diameter 30.85mm, cap diameter 33.85mm
These motor retainers are designed to be interchangeable with Estes BT-20 and BT-50 motor retainers, so if you have lost a cap, you can just print a replacement and use that. If you have an extra cap for some reason, you can print a base to pair with it.
The base glues onto the body tube and the cap screws on to keep the model rocket engine in place.
I included a taller version of the cap because I like to glue a thrust ring in the body tube so ¼ inch of the motor sticks out past the end of the base, making it easier to remove. When you do that you need a longer cap.
I would not recommend printing this with PLA due to the heat exposure. PLA+ might work well enough, ABS for sure. No supports are needed. I printed with a .4 nozzle and .2 layer height with the Outer Wall Line Width to .3 For the BT-20 a .2 nozzle might give a smother result but isn't a must.
Thread specs:
BT-20: pitch 1.525mm, base diameter 22.25mm, cap diameter 23.5mm
BT-50: pitch 2.12mm, base diameter 30.85mm, cap diameter 33.85mm