A Mechanical Freelancing Hub

We've a wooden stool with huge dowels and we want to attach an assembly that can allow a pencil pot to be slotted onto the wooden dowel the whole point is the pencil pot is able to be detached and removed when needed. There are two parts that need to be designed.
1. The immovable base which will be permanently attached to the stool
2. The pencil pot with a slot

What we know:
• Material: plastic only, so please model wall thicknesses and fillets with FDM/FFF printing in mind.
• Form factor: one circular compartment, 12 cm tall, 7 cm internal diameter. No extra dividers.
• Fitment: the outer geometry must seat snugly with the immovable base on the stool; we’ll give you the slot’s exact dimensions and a quick phone-photo sketch once we start.

Deliverables:
1. Editable CAD (STEP or Fusion 360)
2. Print-ready STL with units in millimetres
3. A quick shaded render