Parametric Tilt Window AC Vent Adapter / gekippt

Parametric Tilt-Window AC Vent Adapter

ATTENTION: THE CROSS SECTION OF ALL SECTIONS MUST BE EQUAL FOR BEST AIRFLOW! There are 3 elements in when going from hose to the trapezoidal outside: The HOSE PART (hose radius) , the BEND part (bend_duct_thickness, treat it roughly like a rectangle with slit_height*bend_duct_thickness) and the TRAPEZOIDAL OUTLET (check the formula for it) - all these MUST match or you will get large back pressure and your AC compressor will overheat earlier / cool less / use more electricity!

This is a customizable adapter for venting a portable air conditioner through a tilted / tilt-turn window. It changes from a trapezoid window insert into a smooth curved duct and a round hose spigot, so you can fit different window gaps and almost any AC exhaust hose diameter.

What you can change

Part Main parameters Use

Window slit slit_length, slit_gap_top, slit_gap_bottom Match the tilted-window gap / trapezoid opening.

AC hose hose_radius Set to half your hose inner diameter: 50 = 100 mm, 62.5 = 125 mm, 75 = 150 mm.

Bend bend_radius, bend_angle, bend_duct_thickness Route the hose without a hard kink.

Transitions round_transition_length, inlet_transition_length Blend shapes smoothly to reduce flow loss.

Window lip inlet_flange_width, inlet_flange_angle_from_face Creates a flared stop/lip at the window side.

How to make it airflow-friendly

Rule Simple target

Preserve cross-section Keep the smallest adapter area close to or above the hose area: A = π × (D/2)².

Check the window gap Trapezoid area is roughly slit_length × (top + bottom) / 2. Bigger than hose area is better.

Use a large bend radius If space allows, use centerline R ≥ 1.5 × hose diameter. If not, use the largest radius that fits.

Avoid abrupt steps Increase round_transition_length and avoid sudden contractions/expansions.

Minimize turbulence Smoother transitions + larger radius = fewer eddies and less back pressure.

Quick workflow

- Measure the clear tilted-window gap at the lower and upper end. - Enter those values in the OpenSCAD / MakerWorld customizer. - Set hose_radius for your AC hose. - Increase bend radius / transition length if you have room and want better airflow. - Export, slice, and test-fit before long unattended use. Printing note: PLA can soften in sun or warm exhaust air. PETG/ASA is safer for hot windows. Use enough walls/perimeters around the hose spigot.