18mm model rocket engine storage box

Storage frame for 18mm model rocket engines. It holds up to 5 per stack and has 6 stacks. If you print the one with the sides tilted at the bottom, it is sized to fit in an old red toolbox under the lift out tray.

The stacks have slots on the sides to aid in lifting the engines out when they are down at the bottom, and sloping top sides to make it easier to drop engines in and take them out.

The design is intended to print without supports, as long as you can bridge 2cm. If you can't bridg