Free Multicolor

VentForge - Parametric Vents, Covers & Diffusers

Vent grilles, insect mesh, covers and disc-valve diffusers sized to your wall opening

VentForge - Parametric Vents, Covers & Diffusers is a free browser tool on MakerWorld for custom-size wall vents, duct covers and workshop grilles. Free; MakerWorld login needed. Exports 3MF and STL. Last checked 26 September 2026.

Open VentForge - Parametric Vents, Covers & Diffusers See alternatives

Opens makerworld.com

At a glance

Price: Free; MakerWorld login needed
Runs on: MakerWorld
Exports: 3MF, STL
Multicolor: Yes
Account: Required to download
Open source: No
Skill level: Easy: a few settings to tune
Best for: Custom-size wall vents, duct covers and workshop grilles
Selling prints: On a paid plan Standard Digital File License: no selling prints without permission; the designer sells commercial selling rights through a MakerWorld membership.
How we checked: Read the tool page and docs Model page: 13,602 customizations, 9 function presets from rain louver to disc-valve diffuser, openings up to 500 mm; Customize asks you to sign up first
Last checked: 26 September 2026

Open generator

Sources: MakerWorld model page (description, changelog and licence) (checked 26 September 2026)

Something out of date? Let us know

Made VentForge - Parametric Vents, Covers & Diffusers? Get the listing badge

About this generator

VentForge is a free MakerWorld customizer that makes vent grilles, covers and air diffusers sized to a real wall opening, duct or cabinet cut-out. Made by Rasvodin, it runs in MakerWorld's Parametric Model Maker, so you fill in a form instead of editing OpenSCAD code. It was released in June 2026, reached version 2.3 in August and has been customized more than 13,500 times.

You measure the hole and pick a size preset for common round ducts, flat plastic ducts or masonry shafts or enter your own numbers up to 500 mm. A function preset then sets the type: rain louvers, printed insect mesh, a plain inspection cover, a backdraft shutter, a round disc-valve diffuser that you turn to open or close, or a row of louvers that tilt together from one lever. You can then change the frame shape, corners, 2 to 8 screw holes, louver angle and spacing, and the mesh pattern. Red preview warnings flag risky settings, and the 3MF gives the base, front, mesh and clamp their own colors.

The linked louvers, backdraft shutter and airflow compensation are marked experimental, and the designer advises a small test print before a large one. The designer suggests PLA for indoor vents and PETG for outdoor, humid or warm spots. It suits anyone fitting out a house, workshop or shed who cannot find a store grille in the right size.

What you can make

Rain louver vent grilles
Insect mesh inserts
Inspection and access covers
Adjustable disc-valve air diffusers for round ducts
Backdraft shutter fronts
Linked adjustable louvers

How to use VentForge - Parametric Vents, Covers & Diffusers

Measure the wall opening or duct you want to cover
Open the model on MakerWorld, click Customize and pick the English, German or Polish version
Pick a size preset or enter your own dimensions, then choose a function preset
Adjust the frame shape, screw holes and louver or mesh settings and check the preview warnings
Switch the warnings off, generate and download, then print a small test before the full size

What you'll need to print it

Filament and parts that suit what you make with VentForge - Parametric Vents, Covers & Diffusers.

PETG

M3 screws

Bambu Lab Fastener Kit Bambu Lab
Hilitchi M3 socket head cap screw assortment kit (affiliate link) Amazon

M3 heat-set inserts

Also handy

Digital calipers

Filament dryers and dry boxes

SUNLU FilaDryer S4 (affiliate link) Amazon
Polymaker PolyDryer (affiliate link) Amazon

Some of these are affiliate links: we may earn a small commission, at no extra cost to you. More about that

VentForge - Parametric Vents, Covers & Diffusers pros

Size presets for common ducts and masonry shafts, plus custom openings up to 500 mm
Louvers, mesh, blank covers, shutters and a round disc-valve diffuser all come from one generator
An exploded assembly view, single-part export and on-model warnings help you check the fit before a big print

VentForge - Parametric Vents, Covers & Diffusers cons

The form runs to many sections, and the moving louvers, shutter and airflow options are labeled experimental
Fit depends on your printer and clearances, and big grilles can outgrow the bed, so plan a small test print first
MakerWorld login required, and selling prints needs the designer's paid commercial membership