Nothing Special. Tube OD in Tinkercad was 31.75mm and printed at about 31.75 and fit perfect off the printer without post processing. Adjust for your known printer tolerances.

Im using a lightly modified Anet A8 with a flow rate of 99%. 200 Deg hotend and 80 deg heated bed. Cooling off until layer 3 then 50% unitl layer 5 then 100%, Played with thins until I achieved the best bed adhesion without curling. But still fairly new to 3D printing and learning as I go.

Pxmalion White PLA (prints perfect every time and not issues at all with the entire roll)

.4 Nozzle

.3 Layer

Shell:

- 2 sides

- 3 top and Bottom

10% infill