Bike pedals used to put a metal screw cap to protect the bearings from contamination. Now, instead, use the plastic plugs, which are often lost. Rescue plastic or nylon tubes from medical bubbles. Such substitutes being kept quite steady.
Recommend to read
THE EDGE WILL BE SMOOTH
If you make the fixture shown in the picture, then cropped the Wallpaper strip will have the same dimensions and strict perpendicularity of the cutting line.
Give the trunk aerodynamics too!
To begin with, I suggest that car‑enthusiast readers run a small experiment. Next time you drive out of town, stop on a high‑speed stretch of highway and watch the passenger cars rushing...
