Here the info how to make a pole without a lathe.

Wooden pole (10 inch broomstick): Cone FullLength / Diameter = 3.14 / 1 (must be met exactly!)   Equivalent Angle is 9.5°


Find Center of Pole:
Point with a nail to the center of  wooden pole, and roll the pole over the table
If the nail  is moving up and down then you need to correct the pointing position till you found the center.
Use a pen to mark the exact center
Draw a ring around the pole: Distance from end must be  3,14 x pole diameter

Use a knive and carve the pole conic towards the center point
Do not carve beyond the black ring!

Use a "Feile" (german expression) and a grinding belt to do the "fine tuning"

Cut a deeeep slit
Before you sart to cut you must draw a line along the cone where you want to cut
Draw the line both side of the cone, so you can verify your cutting slit is "on track"

Here another model made from brass by metal lathe:

How to cut inner Tab of Film?

To cut inner Tab of Film I use a tool self made from 2mm spring steel wire, it has a very sharp grinded "slot"

Back side

Front Side

Don't use cheap super glue!

Note: After gluing i use hot air pistol to heat up cone, which has two effets.

a) the film adapts itself to conic form (tensions are relaxed)
b) the glue does harden faster