Laser Hardware
The laser cutter is a cart-mounted appliance. While the laser cutter is cart-mounted, it should not be considered mobile. It has power and exhaust connections that do provide some mobility, but are not designed for continuous movement. The wooden cart holds the necessary auxiliary equipment, as well as supports the laser cutter.
Auxiliary Equipment
The important auxiliary equipment is identified in the following image. <insert image here>
Monitor and Computer
This hardware runs LinuxCNC and provides direct control of the laser cutter, as detailed in other parts of the class. The wireless mouse and keyboard are associated with the LinuxCNC computer. This computer is the main interface to be used when running the laser cutter.
Water Pump
The laser tube itself generates enough heat that it can overheat and crack, which would cause a total failure of the laser. It is water cooled to prevent overheating. The cooling works by using an immersion pump contained in the 5 gallon bucket beneath the cart. The bucket holds a reservoir of water that will work as a heat sink during laser operation. There are limits to the amount of cooling the reservoir can provide, and it is currently not known what sort of duty cycle the laser is capable of without causing issues of over heating.
To prevent failure of the laser tube due to loss of cooling water, a flow switch is installed in the cooling water lines. The laser is incapable of firing when the flow sensor does not detect flow through the cooling lines. If it has been some time since the laser has last been used, it can take approximately 10 seconds of the pump operating before the flow switch will register flow. The flow switch is part of the arming system, which is described below. If at any time a water leak is detected, shut down the laser cutter immediately, provide signage to warn of the danger, and notify the Laser Cutting SME ASAP. The laser power supply reaches voltages of up to 25,000 Volts. It is extremely dangerous, and any amount of water is grounds for immediately stopping and powering down the laser.
The water pump is enabled by the main laser power switch located on the rear panel of the laser cutter.
Air Pump
The air pump is mounted to the bottom shelf of the cart. The air pump provides a constant stream of clean compressed air to the nozzle of the laser cutter. The compressed air is important for two reasons. First, the constant stream of compressed air blows out of the nozzle, which helps prevent smoke from the material being cut (burned) by the laser from depositing on the lens that focuses the laser. Because all of the laser power goes through that lens, anything that collects on the lens can cause it to quickly overheat and shatter. Second, the compressed air provides a constant stream of air that provides a significant amount of fire suppression while cutting. The air stream blows out most material fires before they get larger.
The air pump should run at all times when the laser cutter is running. The air pump is not tied to the arming loop, but the compressor makes enough noise that it is obvious that it is running.
The air pump is enabled by the main laser power switch located on the rear panel of the laser cutter.
Exhaust System
Any time the laser cutter is running, the exhaust system should be enabled. Cutting with a laser cutter makes smoke and other fumes that are at best unpleasant, and at worst hazardous to your health. The exhaust fan controls are currently located on the wall next to the white board. Turn the exhaust fan on high when operating the laser cutter. If you notice a strong smell of burning when operating the laser cutter, check to ensure that the exhaust vent is securely attached to the rear panel of the laser cutter.
Back Panel
The back panel on the laser cutter itself is located on the right side near the bottom (beneath the monitor). The panel contains a power switch. The switch provides power to the laser cutter itself, as well as the air pump and water pump. All three are energized when the switch is on. The LinuxCNC computer and monitor are always powered, so that the files are always accessible. <insert image here>
Front Panel
The front panel has several important controls that change the operation of the laser, as well as status indicators that indicate appropriate operation. <insert image here>