Preface: This document covers some special considerations, warnings, and best practices to ensure your laser operates in an environment where continued performance and reliability are maximized.
Ideally you should operate your machine is a space that is between 60 and 80F, that is dust free with adequate ventilation and non condensing humidity. The machine can operate outside those bounds, even from 20-100F environments but the proper precautions should be taken to handle the extreme temperatures.Setting your Thunder Laser up in a suitable temperature-controlled, dust-free, moisture-free, level, stable surface (a level concrete floor) with the recommended extraction is critical to the ongoing performance of the machine. It is also a warranty condition.
We use a few different laser sources in our machines and depending on the source type, freeze mitigation and ambient temperature strategies will vary based on the source type.
Air-cooled CO2 Sources:
The RF tubes in the Odin series machines are air cooled. On air-cooled tubes, fans blow air across the heat-sinks of the tube to cool the tube. The system temp cannot go lower than the ambient room temperature. Freezing is generally not a concern since water is not involved.
More on RF Excited CO2 Laser Sources HERE.
Water-cooled CO2 Sources:
The glass tubes in the Nova series laser are water cooled and are sensitive to sub-freezing temperatures. The system should ideally run with the water between 15C and 25C. If you have sub freezing temperatures outside, then you need to take precautions to prevent damage to the laser tube. (Damage to the laser tube from freezing is not covered by Warranty)
More on DC Excited CO2 Laser Sources HERE.
Air-cooled Fiber Sources:
The Aurora series galvo sources are air-cooled and coupled to the galvo via fiber optics. The efficiency of the cooling will greatly depend on your ambient temperature. Generally there is no issue with freezing temperatures since the source does not utilize water.
Here is more information on combating extreme temperatures. We want to prevent a tube wall breach or freezing expansion. Frozen tubes are not covered under warranty. As cold weather is approaches, it is time to take steps to mitigate a Glass Laser Tube failureā¦..Even if you live in the South. In previous years, the polar vortex has had deep freezing temperatures down in Texas.
Freeze Prevention
There are a few basic ways to help protect your water-cooled cooling system from freezing.
Heating the workspace
- Keeping the workspace above freezing is desirable. Some use small space heaters when necessary.
- Prevent cold air from entering the machine by disconnecting your exhaust from outside temperatures. Exhaust and Cold Weather
- Open the machine up so that it can acclimate to the room ambient temperature - Main lid and Tube box door at a minimum
- Be familiar with how to drain the Tube and Chiller in case of an extended power outage and freezing temperatures
Draining coolant after use
You can also drain the coolant system when not in use. Use the drain port on the back of the chiller and then disconnect the tubing on the back of the Laser Machine to evacuate as much coolant as possible.
Using Antifreeze Coolant
Antifreeze is not a SET and FORGET solution. Tubes can and will still break even with Anti-Freeze installed.Liquids like water begin to expand as they cool down. Expanding water can crack glass if the pressure has no where to go or is not relieved.We use pure distilled water in DC excited glass water-cooled tubes because it has a conductivity low enough to occupy the tube while 30,000 volts arcs through the tube. Additives can affect that conductivity and can damage the cooling system components, especially with long-term use.
We do have recommendations on the use of antifreeze here: Thunder Laser Approved Antifreeze
And there is more technical data on a variety of additives here: Laser Water Coolants & Additives
Run the machine:
Fire the machine, it will warm the water up and keep the water warmer than if it is just sitting in a cold environment
You can actively warm the water up with a water warmer. Be sure to set the temperature setpoint of warm to below the Chiller's setpoint by at least 2 Degrees Celcius
The Chiller must be put in Constant mode with a Set point set, typically 20c.
Cooling the Ambient Temperature
Keeping the ambient temperature below 80F (27c) is ideal. The efficiency of any type of heat exchanger is affected by high heat ocnditions.
Relocating the machine
In order for your laser cutting machine to function properly, not only in winter but all year round, make sure it is stored in the correct environment. The room temperature should be between 60F and 80F with humidity between 40% and 70% and not in direct sunlight.