Modular roller shutter pass-through for portable split AC

Need to route a portable split AC connecting hose beneath a roller shutter? This insert combines a segmented bar sized to your window with a rectangular hose opening. A removable lid lets you place an already-connected hose inside. Adjust overall width, reduced guide ends and the opening position to suit the installation. What you can customise: Overall width from 300 to 1,800 mm, divided into printable sections. Opening for flat connecting hoses with a separately printed lid. Reduced ends sized to the guides and screw-fastened section joints. How to measure: 1. Measure the clear span, internal guide width and engagement on both sides. Calculate the overall width including both ends and fitting clearance. 2. Measure the hose cross-section and allow room for movement or soft lining. The inputs describe a clear opening, not an interference fit. 3. Locate the opening from the left outer end. Set maximum section length to fit the usable print bed, including the overlap tab. Assembly and trial fitting: 1. Export and print sections 1 to N and the lid separately. The OpenSCAD console reports N and the centre section; 0 exports only the centre section. 2. Use two M3 screws, washers and nuts at each joint. Select screw length for the bar thickness. Tap the lid pilots M3; lid head recesses are Ø 6.6 × 3 mm. 3. Add sealing tape as needed, fit the bar and lay the unbroken hose without strain. Tighten the lid gently. Lower the shutter under control and check that the hose remains clear. 3D printing notes: Segments and lid are output flat. Use local supports beneath the overhanging half-lap tabs and remove them after printing. ASA is a possible choice for sun exposure; account for print conditions and warping. Starting profile: 0.2 mm layers, five walls, 35% infill. This profile has not been physically tested. Fit and included geometry: For rectangular openings 20–100 mm wide and 6–35 mm high, subject to bar height. This is not an adapter for large round exhaust hoses. The insert must not support the AC unit or an uncontrolled shutter-motor load. Follow the device maker’s hose bend-radius and installation requirements. Weather sealing and thermal performance are unverified; seals and fasteners are separate.