Mimaki 3DUJ-553 garage lab · odor exhaust

Garage Vent Kit

The complete exhaust-and-makeup-air system for the printer room: four parts, about $260 in parts, one 6-inch hole through the exterior side wall and one filtered grille cut into a garage-door panel. Any HVAC or handyman crew installs it in half a day — and the airflow is balanced so a gas water heater or dryer sharing the garage is unaffected (numbers below).

Note, 24 Oct 2026 — this is not the design being built for the Beltramo garage lab. That room went with recirculating filtration instead: a filter unit beside each printer, no wall penetration, because every CFM this kit exhausts has to come back in as conditioned makeup air. The parts and airflow numbers on this page are still correct if you are ducting a room — see Garage Print Lab for the design that was chosen and why.

The four parts

1 · Inline duct fan — AC Infinity CLOUDLINE S6

$99

The mover. 6-inch EC fan with a 10-speed controller — 425 CFM flat out, but it runs at speed 2–3 here, near-silent (~30 dB max), which matters with the bedroom above. Mounts in the duct run with the included clamps. model AI-CLS6

AC Infinity direct Home Depot Amazon

2 · Carbon filter — AC Infinity 6″ Duct Carbon Filter

$69.99

The odor eater. Hangs inside the room at the intake end of the chain; room air is pulled through the Australian-charcoal bed before it ever reaches the fan. Rated 410 CFM — matched to the S6. Cartridge is replaceable every 12–24 months. 6″ × 16″ · RC-412 charcoal

AC Infinity direct Amazon

3 · Exterior wall cap — Master Flow 6″ with screen & damper

~$34

The dryer-vent-size termination on the outside of the side wall. Gravity damper flaps shut when the fan is off; screen keeps birds and critters out. (Broan-NuTone 646 louvered cap is an equal substitute if it's what the store has.) model WVA6SD · Home Depot SKU 205375574

Home Depot SupplyHouse (Broan 646 alt)

4 · Makeup-air inlet — Everbilt 14″×20″ return-air filter grille

~$47 + $10 filter

The inlet — deliberately oversized. Cut into a garage-door panel, low, on the corner opposite the exhaust. It holds a standard 14×20×1 furnace filter (MERV 8, ~$10, any brand), so incoming air is cleaned before it reaches the printers — dust on a print mid-job is a ruined print — and the big free area is what keeps the room's pressure drop near zero (see airflow balance below). Rinse-or-swap the filter monthly. model H190 14X20 · Home Depot SKU 202525291 · + 14x20x1 MERV 8 filter

Home Depot Amazon

Sourcing in one trip: order the fan and filter from acinfinity.com or Amazon (two days); pick up the wall cap and louver at any Home Depot — walk in with the model numbers WVA6SD and H190 14X20 and the HVAC aisle has both on the shelf. Add ~8 ft of 6-inch semi-rigid aluminum duct, four worm-gear clamps, and a 14x20x1 MERV 8 filter (~$35 together) while you're there. If a Home Depot link above gets stuck on a store-picker or robot check, just search the model number on homedepot.com — the SKUs are listed on each part.

Where everything goes — floor plan

makeup air in exhaust out duct & equipment

Exhaust on the left exterior wall, inlet low in the opposite garage-door panel: incoming air has to cross the whole room — past both printers — before it leaves, so nothing stagnates. The room runs at slight negative pressure, which is what keeps resin odor from reaching the house or the bedroom above.

The vent is room-level odor control — nothing connects to the printers themselves. Mimaki lists no venting requirement; this is our recommendation for living with resin odor at a residence.

How the airflow balances — gas appliances stay safe

The exhaust fan puts the room under slight negative pressure (that's what keeps odor out of the house). An atmospheric-draft gas water heater or gas dryer in the same garage relies on gentle buoyancy up its flue, and strong depressurization — about −3 pascals — can reverse that draft and spill combustion gases into the room. The design handles it by oversizing the inlet and capping the fan:

The numbers

Fan runs at speed 2–3 ≈ 100–150 CFM (the room is ~3,200 cu ft — that's a full air change every 20–30 minutes, plenty for odor). The 14″×20″ filtered grille gives ~2 sq ft of free area, so intake face velocity stays near 75 ft/min. Pressure drop scales with velocity squared, which lands the room at well under −1 pascal — a 3× margin to the −3 Pa backdraft threshold, filter included.

Two conditions that make it code-defensible

1 — Put a physical stop on the fan's speed controller so it can't be cranked to its full 425 CFM while gas appliances share the space. 2 — Have the bidder do the thirty-second smoke-pencil test at the water heater's draft hood with the exhaust fan and the dryer both running (the worst case), and note the result for the permit file. A sealed power-vent or direct-vent water heater is immune and needs neither.

The dryer's own exhaust

A dryer is itself a ~150 CFM exhaust fan fighting ours for makeup air — the oversized grille is sized for both running at once. Keep the dryer's duct run to the outdoors (never into the room), and keep lint away from the intake: lint is printer poison, which is the other job the MERV 8 filter does. California notes while the bidder is there: burner 18″ above the floor unless the unit is FVIR-listed, and seismic strapping on the water heater.

Install notes for the bidder

One 6¼″ core hole through the exterior side wall (not the front) for the wall cap; seal and flash it.
Hang the carbon filter from the ceiling or a wall bracket near the printers; fan in line after it; short semi-rigid duct run to the cap. Rubber-mount the fan — the bedroom is directly above.
Cut the 14″×20″ filtered grille into a lower garage-door panel on the corner opposite the exhaust. No second wall penetration needed. Load it with a 14x20x1 MERV 8 filter.
Fan plugs into any receptacle — it draws under 40 W. Do not put it on the printer circuits. Set a physical stop at speed 3 on the controller if gas appliances share the garage.
Run the fan whenever the printers run; the speed controller lives at ear height by the house door.
If a gas water heater or dryer is in the garage: smoke-pencil test at the draft hood with fan and dryer both running, per the airflow-balance section.

Rule of thumb on sizing: the room is roughly 3,200 cu ft; the S6 at speed 3 turns the air over about every 10 minutes, which is plenty for odor control while costing almost nothing in conditioned air.