When embarking on the creation of a plasma cutter, the initial step involves a meticulous examination of all components. As detailed in Sections 5 and 6, arrange your parts strategically, enabling a systematic verification against your comprehensive parts list. Following this crucial inventory check, dedicate time to thoroughly studying the pictorial representations of each part/component, familiarizing yourself with their individual characteristics and intended placement within the overall assembly.
The subsequent and arguably most vital step is the development of a detailed schematic and layout diagram. This diagram serves as an indispensable resource throughout the entire lifecycle of your plasma cutter, from initial construction and subsequent repairs to potential modifications and enhancements. A well-defined layout diagram provides a clear roadmap, minimizing errors and streamlining the entire process.
As you begin the physical mounting of components onto the board, adopt a structured approach by logically organizing the board into distinct sections, each dedicated to a specific function. A recommended segmentation includes: Power Control, High Current DC, Low Voltage DC, and High Voltage Arc Start. This modular design simplifies troubleshooting and allows for focused maintenance.
The Power Control section typically incorporates a 3KVA step-down transformer and a contactor. Due to its substantial size and weight, the transformer is often mounted off-board, as illustrated in Section 13. The contactor should be the first component installed on the board. Wire the contactor in such a way that pressing the head trigger activates it, thereby energizing the DC components within the system. Following the contactor, proceed with the assembly of the High Current DC system.
The High Current DC system commonly consists of a bridge rectifier, large capacitors, and a reed switch, which functions as a current sensor. The reed switch plays a critical role in enabling the high voltage arc system to initiate the cutting process. Once a sufficient high current begins flowing to the cutting head, the reed switch deactivates the high voltage arc system, as it is no longer required during active cutting. Should the arc be interrupted for any reason, the system automatically reignites the arc, ensuring continuous operation. Once this system is built, move on to the Low Voltage DC system.
The Low Voltage DC components are often integrated with the power switch and 120-volt terminals. This section typically includes a power switch, 120-volt terminal blocks, a 12-volt transformer, a low voltage bridge rectifier, auto relays, and a terminal strip (a 4-position strip may suffice, but a 5-position strip can be used if readily available).
The High Voltage Arc Start system generally comprises a microwave capacitor (or run capacitor) and a household dimmer switch rated for 15 amps. Additionally, an ignition coil from a Ford or Chevy vehicle is required. In this particular guide, a Chevy ignition coil was utilized. To facilitate easy connections, it’s recommended to install terminals for all parts requiring external connections outside their respective systems. This allows for simple wiring between components. Refer to the pictorial representation of the board-mounted parts in Section 11 for a visual guide to the wiring layout. When wiring all components, make sure to use the Chevy board layout diagram for guidance.
Before proceeding with the mounting of external parts, it is imperative to meticulously check and re-check all wiring connections. Refer to the final wiring section for detailed pictures illustrating the rigging of these parts. While alternative configurations are possible, the described method represents one viable approach.
The actual assembly process may take approximately three hours, depending on the level of procrastination involved. It is common for builders to experience a period of contemplation, exploring various approaches and optimization possibilities. Ultimately, a decision must be made to commit to a specific methodology and proceed with the construction.
Once the entire assembly is complete, connect the air tank hose and set the pressure to a safe starting point, such as 28 PSI. Upon powering up the system, the plasma cutter should ideally function without requiring further adjustments, initiating the cutting process immediately.
The successful creation of a functional plasma cutter can be a rewarding experience, filled with a sense of accomplishment and pride.
In conclusion, building a plasma cutter involves careful planning, methodical assembly, and attention to detail. By following these steps and referencing the provided diagrams, you can successfully construct your own plasma cutter and experience the satisfaction of a successful DIY project. Remember to always prioritize safety and consult with experienced professionals if needed.
