Thunder Laser External Air Compressor Guidelines

Thunder Laser External Air Compressor Guidelines

Preface: This article describes adding 3rd party bolt-on performance peripherals. Your stock Thunder Laser will run to our specifications right out of the box with the included high quality accessories. This guide is catered to the newer Dual Air Thunder Laser Nova and Odin machines.

Setting your pressure higher than 55psi can cause your solenoids to prematurely fail. Any damage from the over-pressure to any machine component will not be covered by warranty.

Install, Setup and Basic Operation:

Below is a "High Level" overview of the basic layout of the External Air installation on your machine. Each install will be a bit different, you may have a more complex scenario like multiple machines etc.


Point of Interest
Reference Picture
Where to Plug the Air In

You will plug your new external air feed line into where the original pump was plugged into. It will be on the back of the machine. For Nova Series, it is on the side by the chiller connections. For ODIN series it is underneath the tube box area on the back, below the power connections.

Where to Power the Compressor From

You will need to power the External Air Compressor from its own dedicated Electrical connection. Do not under any circumstances power the External Air Compressor from the stock Air Pump power port


What pressure to Set on the Compressor Regulator

Thunder recommends setting the supply regulator on the External Air compressor at least 20psi higher than what is set on the Machine Air Regulator but no higher than 90psi

You should monitor the regulator while the machine runs to check for pressure drop and adjust as needed.

Pressure is set "Static" while air is not flowing. If you set the pressure while air is flowing, the "Static" pressure will be much higher.

(Adjust the knob on the compressor to set to the pressure after the tank is full)
What Pressure to set on the Machine Air Regulator

You can set the pressure between 5-55psi. We recommend staying below 50psi to allow for regulator variability.

Pressure is set "Static" while air is not flowing. If you set the pressure while air is flowing, the "Static" pressure will be much higher.

Setting your pressure higher than 55psi can cause your solenoids to prematurely fail. Any damage from the over-pressure to any machine component will not be covered by warranty

(Adjust the machine regulator after you have adjusted the Compressor regulator)
Basic Operation and Shutdown

Your new setup will not act the same way as your stock pump. You will need to turn the External Compressor on before beginning to run your laser so that the compressor has time to fill the tank. You will do this with the manual switch on the External compressor. The pressure in the tank will trigger an automatic Pressure Sensing switch to tell the compressor to kick on and off.

At the end of the day, you need to turn off the compressor, drain the compressor and drain the air line on the machine by using the Green High test button.

                      (Use your specific Compressor manual to locate the On/Off switch)

Basic Components for External Air Connection:

Reference Image with Links (click the pic)
Air Compressor Quick Connect

The common air compressor outlet is a 1/4" quick connect. You should be able to find these at your typical big box hardware store.

You will want the Female connection threads so that you can install a Push to Connect air fitting with male threads.

(This kit from Home Depot has both)

Quick Connect to Push To Connect Air Fitting

This fitting will adapt the Quick Connect fitting to 6mm (1/4") air tubing so that you can run the tubing to your regulator inlet.

This fitting will be harder to find at your local hardware store.  You can use fittings meant for 1/4" tubing as well.

Air Tubing

You will need some 6mm tubing. It is best to get a kit with a variety of fittings to have on hand and it is only a few bucks more.

This kit also comes with a tubing cutter and thread sealant tape which is good to have for all the threaded fittings.

Push To Connect Fitting For Regulator Inlet

You need a fitting to adapt the air regulator inlet to the 6mm tubing. Your regulator may have a different size thread so make sure you order the correct size. The common size is the 1/4" npt shown.

Regulator\Water Separator

This is an example of a Regulator with some water separators on it. There are many options online, better brands, higher cost versions etc. You need to find the one that meets your budget and needs.

You also need to note what the thread of the inlet and outlet are so that you can purchase the proper fittings to adapt to 6mm tubing. The model shown has 1/4" npt but there are options for other sizes.

Push to Connect Fitting for Regulator Outlet

You need a fitting to adapt the air regulator outlet to the 6mm tubing. Your regulator may have a different size thread so make sure you order the correct size. The common size is the 1/4" npt shown.

Things to consider when selecting a compressor:

What to Consider
Cubic Feet per Minute (CFM) Rating

As you increase the pressure of the line, the amount of CFM required will also increase. If you set the pressure too high, you will drain the tank if the compressor cannot exceed the CFM.

So as you buy a compressor, compare the CFM rating at 40psi.

Take note of the chart from Engineering Toolbox showing the relationship of Flow and Pressure settings. Note that the 6mm tubing will flow similarly to the 3/16" hose shown.
air volume discharge through hose
Tank Volume

Tank volume will allow for longer run times between compressor cycles but the trade off is the space that the compressor will take up. 

If you plan to run a higher pressure, then you should consider having a higher volume tank.
Husky 20 Gal. 200 PSI Oil Free Portable Vertical Electric Air Compressor  C202H - The Home Depot
Duty Cycle

As the tank is depleted, the compressor has to cycle on and off to fill it back up. This is the duty cycle. Most compressors like a 70% duty cycle.  You can find some that are 100% continuous rated cycle.

If you have the pressure set too high, the compressor will have to exceed the Duty Cycle to keep the tank filled. And if you exceed your tanks CFM and Duty Cycle, the tank may actually empty out while your laser is running.

Noise Level

Each compressor manufacturer may have a "Quiet" rating on their compressor but not all of the ratings are the same. Depending on your space, you may want a very quiet compressor. Generally speaking the lower the noise rating, the more expensive the compressor will be.

The noise will be rated in dB. The lower the dB, the quieter the compressor

Power Requirements

120v or 220v and current rating of the compressor itself. Generally the larger the compressor, the higher the amp draw which is why they will build them for 220v since that basically halves the current draw. Make sure you have the proper break, wiring and ampacity for the compressor you select

Do not power your external air compressor from the laser machine. The external air compressor should be on a separate dedicated circuit


Buy once, cry once. Get the compressor that fits all your needs but one that is also in your budget.

How to find Air Pressure Setting Limit of your Compressor:‚Äč

The limit is 55psi, but can your compressor keep up? Most compressors are rated for a 70% duty cycle (Higher priced ones will run 100%) and can produce a CFM (cubic Feet Per Minute) rating of air at 90\40psi on their spec sheet. If your compressor produces a low CFM then it will not be able to keep up with your Laser Machine High Air pressure consumption rate. To test this, fill up your compressor and set your PSI at the laser machine regulator to 55psi (compressor regulator at 90psi) and then use the TL timer board to trigger your Air Assist control( Testing/Adjusting Peripheral Systems using The TL Timer) and open up your high air assist all the way. Start a time and watch the tank on the compressor lower PSI until the compressor kicks on and then time how long it takes for the compressor to fill the tank back up.

-If the tank never fills back up and depletes completely, reduce your laser machine PSI by half (so say 55 down to 28) and retest
-If the compressor is rated at 70% duty cycle (check with your specific model) compare the time it took the compressor to fill the tank divided by the cycle time (time to fill + time to deplete). If the duty cycle exceeds your compressor rating, then reduce your Laser Machine Regulator by a few PSI and retest
-If the compressor is able to operate at under its rated duty cycle, then you can raise the Laser Machine Regulator PSI up a few PSI and retest but do not exceed 55psi.
-Once you are close to the rated duty cycle of your compressor, that will be the max PSI of your Laser Machine Regulator and you will have max flow with the High Air Assist nozzle all the way open. this will make sure you do not lose High Air pressure during a long cut job which will make your cutlines dirty and reduce the performance

Single Air Machine Considerations:

If you have an older machine that does not have Dual Air or an External air port you may need to make some additional modifications to make external air work.  You can get a 110VAC solenoid and plug  wire it for the stock air pump outlet on the back of the laser or you can get a 24VDC one and go to the trigger of the relay for the air pump. Then run your external air compressor through the solenoid.

Example Setup of External Air:

When running your compressor in another climate compared to your machine, you will want to be diligent about moisture.

Testing Max Air Pressure, at some point more air is pointless:

(Note that this testing was done without using the stock Air solenoids and was for testing purposes only).

    • Related Articles

    • Plug Adapters for External Exhaust Fans and Stock Compressor

      The stock wiring in the Thunder Laser Machine is rated for 10amps. Do not exceed more than 10amps (1200watts) of load per plug (exhaust fan and compressor output each. Total load should not exceed 10 amps. Plug identification: General location on the ...
    • Quantifying Air Assist Pressures

      Introduction The air assist is critical for keeping flare-ups at bay, mitigating smoke, helping keep the lens cleaner and cooler (it really shouldn't get that hot if it is in proper order anyway), and, when cutting, catalyzing the ablation of ...
    • How to Align your Thunder Laser Nova Series machine - Quick Start Alignment Guide

      Preface: This article covers How To align your laser beam in a 3 mirror gantry based Nova laser. Here are some quickstart videos that will cover 90% of the situations. They do not contain every last iota of detail but should be enough to get most ...
    • Venting The Exhaust From Your Thunder Laser

      Preface: This article covers some key points about Venting Your Laser and adapting aftermarket exhaust components Important Considerations: Existing Systems Do not connect the exhaust output of this laser to an existing exhaust system. Please consult ...
    • Thunder Laser Dual-Stage Air Assist Sequencing Issues

      Thunder Lasers with dual-stage air assist systems sometimes experience sequencing issues. This anomaly is predominately occurring when the laser is connected to the computer via USB (or thunderbolt/USB-C adapters). If you toggle air assist ON in ...