Do not connect the exhaust output of this laser to an existing exhaust system. Please consult a qualified HVAC or industrial mechanical professional to help you plan and install your system.

Even if you have great exhaust flow out, you must have the same volume of air coming in. This can be realized easily if you are in a somewhat airtight area like an interior room in your home or business. The negative ambient pressure is created by the laser sucking 300-1100 CFM out of the room, depending on setup and fan. If the incoming air into the room and the laser is not sufficient, the fumes will not escape. 

Often by having a window on an opposite wall open, intake Louvers, or a slightly raised garage door, you can feel the air flow into the space as the laser exhaust operates

Exhaust fans work better when pulling air away vs pushing through the duct. When the fan is pushing air through the duct, the duct becomes positive pressurized and that is when fumes and dust can escape the duct more easily. When pulling air, the duct becomes negative pressurized  (vacuum) and any leaks would also then pull in air into the duct, keeping fumes and dust in.

The best solution is to mount the fan right at the exit (or as close as possible which may require an extension cable, more information below) so it pulls the exhaust though the ducting. Some mount their fans outside and have a true negative pressure system. We should clarify that mounting the blower on the exterior is only for fans that are sheltered and/or rated for outdoor use.

Here is one setup where the fans and exhaust systems are easily accessible for inspection and maintenance. The fan outlet is less than 24" from daylight. The left one is a Cloudline S6 and the one on the right is a 4" S series. The components in this article were used in this installation:

 

And, restrictions of any kind can cause major issues. Use the shortest runs possible with minimal bends and turns. The helix reinforced cloth flex ducting is plasticized but it can still be permeable if under pressure.  Rigid ducting is recommended for long and/or complex runs. 

It is important to get a vent hood with a damper to keep the outside air from entering the laser, especially in the winter. Cold air from the exhaust system can affect the Laser Tube temperature. 

If conditions are below freezing this could be an issue. It may be beneficial to leave the Machine Lid Up and Tube Door Open on your machine to help equalize temperature inside the machine closer to the ambient temperature of your space 

A spring-loaded damper may be more efficient at remaining completely sealed but if and when the spring fails, the damper is rendered largely ineffective. 

A weighted damper is less prone to failure. The exhaust system must also be periodically inspected, cleaned, and maintained for optimum performance and safety.

Description	Example and Link
Available in 4" and 6" 2-in-1 wall vent hood converts from exhaust to intake by removing damper Innovative damper design prevents back-draft and heat loss Designed for energy efficiency and maximum airflow
Available in 4", 6" , 8" and 10" MADE IN THE USA: Our hooded aluminum wall vent covers for home are constructed using quality, heavy duty 28 gauge galvanized steel, with the most extreme conditions in mind. The FAMCO hooded wall vent includes a protective mesh screen. ADAPTIVE EXHAUST VENT: The FAMCO SWV Wall Vent is primarily used for air intake, air supply, or exhaust applications where no backdraft damper is needed. The angled hood is designed to balance a low profile with optimum air and exhaust flow. Includes a 1/4 inch mesh screen to prevent foreign objects from entering the duct. SELECTION: Our vent covers for home is available in sizes ranging from 3” to 14 inches. NOTE THE SIZE REFERS TO THE DIAMETER OF THE PIPE. Our low profile vent covers are also available in Aluminum and Copper. INSTALL: Our air vents are made from durable materials making it easier to install and compatible with most home improvement projects. Please note this Wall Vent has NO DAMPER. Please see our SDWV Wall Vents for a vent with a screen and damper. Please note this wall vent is not rated for dryer ventilation. The screen may trap lint and could create a fire risk.

A blast gate can be used to greatly reduce outside air flowing back into the machine. If you are in an area with extended cold days and the laser is not in use, disconnect the exhaust system completely from the outside air source. Opening the lid of the machine, Laser Tube door and the Front Access will also allow the laser to acclimate better to the garage Ambient Temperature while the machine is not in use.

The examples below may require reducers or adapters for the hoses to fit as well as additional mounting considerations.

Example Description	Example
FOR 4-INCH HOSES, OUTLETS, AND PORTS - Circular center has a nominal 4 inches outer diameter with actual dimensions of 3 3/4 inches ID, 3 61/64 inches OD. Accepts hoses and ports with 4 inches ID REQUIRES A COUPLER - The blast gate will not connect directly to outlets or ports with 4 inches OD. You will need a coupler/ connector like our flexible hose cuff couplers with integrated dust hose clamps SLIDING GATE FOR EASY AIRFLOW CONTROL - The manual sliding gate has a pull tab for easy airflow control. It allows for an airtight seal as needed LIGHTWEIGHT YET DURABLE - Made of wear and abrasion-resistant black ABS plastic. Designed to withstand high air flow rates and resist damage from debris
6" Model Model Number: W1009 Item Package Dimension: 9.5" L x 8.6" W x 3.4" H
Cast Aluminum body Galvanized blade Set screw Shuts off air when not needed Manual Style

Machine	Duct Size	Airflow	Noise	Link
Mini 60	6"	323 CFM	26 dB	W150
Odin Series	4"
Aurora V1	3"	27 CFM	26 dB	HF-75S
Nova 24	6"	323 CFM	26 dB	W150
Nova 35	6"	482.6 CFM		CZ-TD550
Nova 51	6"	482.6 CFM		CZ-TD550
Nova 63	6"	482.6 CFM		CZ-TD550

Machine	Duct Size	Airflow	Noise	Link
Mini 60	6"	323 CFM	26 dB	W150
Odin Series	6"	312 CFM		HF-150PE
Aurora V2	4"	215 CFM		HF-100PE
Nova 24	6"	382 CFM		HF-150PE
Nova 35	6"	382 CFM		HF-150PE
Nova 51	8"	735 CFM		HF-200PE
Nova 63	8"	735 CFM		HF-200PE
Bolt Series	4"	215 CFM		HF-100PE

AC Infinity Cloudline S-Series Inline Exhaust Fans

Since Thunder Introduced the quiet Inline fans in Q3 2022, you do not need to use an aftermarket fan. The reason people used to buy aftermarket fans is was generally for noise mitigation, not performance. 

This is some basic info on AC Infinity Cloudline S-series axial inline exhaust fans

Model	S6	S8	S10	S12
Duct Size	6"	8"	10"	12"
Dimensions	7.9 x 12.6 x 8.4 in.	8.5 x 11.9 x 9.2 in.	11.3 x 15.1 x 12.2 in.	12.2 x 17.7 x 14.0 in.
Airflow	402 CFM	807 CFM	1201 CFM	1604 CFM
Noise	32 dBA	39 dBA	48 dBA	62 dBA
MSRP (Feb.2021)	$109	$169	$269	$369
Link	S6 LINK	S8 LINK	S10 LINK	S12 LINK

Connecting an aftermarket fan to your Thunder Laser

DO NOT USE AN ADAPTER LIKE THIS TO RUN AN EXTERNAL AIR COMPRESSOR FROM THE COMPRESSOR JACK ON THE LASER.

THIS IS FOR ADAPTING THE EXHAUST FAN TO ACCEPT AN AFTERMARKET INLINE FAN.

You can connect an exhaust fan that does not draw more current than your stock fan. You will find that info linked above. To do this you will need an IEC 60320 C14 Male to NEMA 5-15R Female 10A adapter like this:

Description

Reference Image and Product Link

AC COMPUTER POWER CORD: This 1ft (0.3m) 18AWG AC power extension cable with IEC 60320 C14 to NEMA 5-15R connectors is suitable for workstations/home office | Indoor use | Rated to carry 125V at 10A PERFORMANCE AND SAFETY: UL listed (UL62 & UL817) | Fully molded strain relief connectors for durability | Fire Rating: VW-1 | 3 Conductor extension cord made with 100% copper wire | This C14 to 5-15R power extension cord is available in other lengths SPECS: 1ft (0.3m) AC Power Cord | IEC 60320 C14 to NEMA 5-15R | 18AWG | 125V 10A (Max) | Jacket Type: SVT | Jacket Material: PVC | Black | Temperature Range: 37°F to 140°F (3°C to 60°C) | Cable Outer Diameter: 0.24in (6.1mm) COMPATIBILITY: PC Power Extension Cord NEMA 5-15R works with North American cables | Extend a 3-prong power connection from your desktop computer, server, or printer | Replacement power supply cable/cord

Extending the stock Fan Power Cable

The fan power cable can be extended using a c-14 to c-13 extension cable, like below:

Description

Reference Image and Product Link

HEAVY-DUTY PERFORMANCE: IronBox Electric presents a robust C14 to C13 Power Cord built with precision using top-grade materials. The 14/3 AWG computer extension cable ensures a powerful connection, making it ideal for demanding tasks in your setup. VERSATILE POWER SOLUTION: Designed as a PDU Power Cable, this IronBox Electric product is perfect for your PC adapter, server rack, and monitor. Its versatility makes it a reliable choice for devices, offering a seamless extension to your power sources. HIGH POWER CAPACITY: With a rating of 15A and 250V, this power cord delivers substantial electrical capacity, ensuring your devices receive the power they need for optimal performance. The durable design guarantees a efficient power supply for your equipment. DURABLE AND FLEXIBLE: The IronBox Electric Power Cable boasts a sturdy construction, making it a reliable replacement for worn-out cords. Providing flexibility in positioning your devices, it offers convenient placement options without compromising.

Roof Venting

Farbulous Creations did a great video on exhausting through the roof, but there is a lot of great info even if you are not going through the roof.