Shop-Vac 2.5 inch hose to 35 mm tool dust adapter
A stepped reducer that joins a Shop-Vac, Craftsman or Ridgid 2.5 inch (63.5 mm OD) hose end to the 35 mm dust port found on most European sanders and track saws from Bosch, Makita and Festool. The wide end is a 64 mm bore 40 mm deep with a 1 degree taper so the hose cuff pushes in and seals; the narrow end is a 34.6 mm outer spigot 35 mm long with the same taper to grip the tool port, and the 45 degree cone between them keeps chips moving. Walls are 2.5 mm; print it upright in PETG or TPU for a flex fit with 3 perimeters and no supports.
Vacuum fittings are almost never truly standard, so a downloaded adapter is either loose or needs tape. In SpeakCAD you type the two measured diameters, preview the reducer in the browser without paying, change taper or length in the chat, and download the STL.
Model a hose adapter 100 mm long with a female end 64 mm inner diameter, 40 mm deep, tapered 1 degree, a male end 34.6 mm outer diameter and 35 mm long tapered 1 degree, a 45 degree transition cone between them, 2.5 mm walls and a 2 mm stop ring at the female end.