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  • Holes and Knockouts – Pipes, connectors

    To create knockout holes in electrical panels, several tools are recommended:

    1. Hydraulic punch set: This is one of the best tools for creating clean, precise holes in electrical panels. It consists of a hydraulic pump, punch dies, and draw studs6.
    2. Knockout punch set: These manual punch sets are effective for creating accurate holes in electrical panels. They come in various sizes and can punch through mild steel, aluminum, fiberglass, and plastic23.
    3. Hole saws: These are suitable for drilling holes in panels and come in sizes corresponding to standard knockout sizes4.
    4. Electrical panel knockout kit: This specialized tool is designed to open knockouts without damaging the panel or surrounding drywall1.

    To measure the correct size for a knockout hole in a panel:

    1. Determine the trade size of the conduit or connector you’ll be using. This is the standard label used in the electrical industry.
    2. Refer to a knockout size chart or guide to find the corresponding hole size for your trade size. For example:
      • 1/2″ trade size requires a 7/8″ (22.5mm) hole
      • 3/4″ trade size requires a 1-1/8″ (28.3mm) hole
      • 1″ trade size requires a 1-3/8″ (34.6mm) hole4
    3. Use precise measuring tools like a tape measure or caliper to mark the center point of the hole on the panel.
    4. Consider using a center punch to create a small indentation at the marked point, which will help guide your drill bit or punch tool6.
    5. For multiple knockouts, you can use a layout tool like the Center Point Knockout Layout Tool to quickly and accurately mark the centers of desired conduits5.

    Remember to always follow safety guidelines and use appropriate personal protective equipment when working with electrical panels and tools.

    For beginners creating knockout holes, there are several recommended tools that are easier to use and more affordable:

    1. Manual knockout punch set: This is a good starting point for beginners. It’s less expensive than hydraulic options and allows you to get familiar with the process12.
    2. Hole saws: These are versatile and can be used for various materials. They’re a good option for beginners who may not be ready to invest in a specialized knockout tool2.
    3. Step bits: These are useful for making smaller holes and can be a good addition to a beginner’s toolkit2.
    4. Greenlee Slug-Buster Knockout Punch Set: This manual set is often recommended for its ease of use and effectiveness3.
    5. Klein Tools Knock-Out Punch Set: This is another manual option that’s great for beginners working on smaller projects, like adding a circuit to a box7.

    When starting out, it’s important to practice proper alignment and technique. Many knockout sets come with alignment markings or crosshairs to help ensure accurate hole placement12. As you gain experience, you can consider upgrading to more advanced tools like hydraulic or battery-powered knockout sets.

    Remember to always prioritize safety and follow manufacturer instructions when using any hole-making tools.

    For beginner-friendly knockout tools that are lightweight and easy to use, consider the following options:

    ToolFeaturesWeight/DesignEase of Use
    Greenlee 7238SB Slug-Buster KitManual punch set for 1/2″ to 2″ holes, alignment markings for accuracyCompact and lightweightSimple manual operation with included wrench
    Pittsburgh Knockout Punch KitAffordable manual kit for punching holes in steel, aluminum, and plasticLightweight 10-piece kitIdeal for basic tasks; easy for beginners
    Klein Tools Knockout Punch Set with Wrench3Includes punches, dies, and ratcheting wrench for 1/2″ to 2″ holesCompact design; cuts up to 10-gauge steelClean and accurate punching with manual control
    iTOOLco Gear Punch Kit2Works with any drill, punches 1/2″ to 4″ holes, lifetime warranty on draw studsLightweight and drill-compatibleEasy setup with Center Point alignment tool

    Manual knockout punch kits like the Greenlee or Pittsburgh are cost-effective and beginner-friendly. For added convenience with a drill, the iTOOLco Gear Punch Kit is a versatile option.

    Based on the search results, the most versatile knockout tool for different materials appears to be the Milwaukee M18 FORCE LOGIC Knockout Tool. Here’s why:

    1. Material versatility: It can punch holes in various materials, including mild steel, stainless steel, aluminum, brass, copper, fiberglass, and plastics13.
    2. Punching capacity: The tool can punch up to 4″ holes in 14 gauge mild steel, making it suitable for a wide range of applications4.
    3. Power and force: It delivers up to 10 tons of hydraulic force, enough to punch through tough materials like stainless steel3.
    4. Cordless design: Being battery-powered, it offers more flexibility and portability for working in different environments and tight spaces3.
    5. Quick Connect system: This feature simplifies setup and ensures accurate alignment, making it easier to work with different materials and hole sizes3.
    6. Compatibility: The tool is part of Milwaukee’s M18 battery platform, which adds to its versatility across different job sites and applications3.

    While other tools like the Greenlee knockout sets also offer versatility, the Milwaukee M18 FORCE LOGIC Knockout Tool stands out for its combination of power, portability, and ability to work with a wide range of materials and hole sizes.

  • Standard sizes for the various round electrical panel knockouts

    Electrical panel knockouts and their corresponding hole sizes for drilling come in several standard sizes:

    1. 1/2″ trade size: 7/8″ (22.5mm) hole2
    2. 3/4″ trade size: 1-1/8″ (28.3mm) hole2
    3. 1″ trade size: 1-3/8″ (34.6mm) hole2
    4. 1-1/4″ trade size: 1-3/4″ (43.2mm) hole2
    5. 1-1/2″ trade size: 2″ (49.6mm) hole2
    6. 2″ trade size: 2-1/2″ (61.5mm) hole2
    7. 2-1/2″ trade size: 3″ (74mm) hole2
    8. 3″ trade size: 3-5/8″ (89.9mm) hole2
    9. 3-1/2″ trade size: 4-1/8″ (102.7mm) hole2
    10. 4″ trade size: 4-1/2″ (115.4mm) hole2

    When drilling these holes, you can use either a hole saw or a conduit knockout punch of the corresponding size2. For example, for a 1/2″ trade size conduit, you would use a 7/8″ hole saw or a 1/2″ conduit knockout punch2.

    It’s important to note that the trade size does not directly correspond to the actual hole size. The hole size is typically larger to accommodate the fittings and connectors used with the conduit.

    The difference between ‘trade size’ and actual size in electrical conduit is sigThe difference between ‘trade size’ and ‘hole size’ in electrical conduit and knockouts is significant:

    1. Trade size: This is a standardized label used in the electrical industry to identify conduit sizes. It does not directly correspond to the actual physical measurements of the conduit or knockout3.
    2. Hole size: This refers to the actual diameter of the hole that needs to be drilled or punched for the conduit to fit properly1.

    For example:

    • A 1/2″ trade size conduit requires a 7/8″ (22.5mm) hole1.
    • A 1″ trade size conduit needs a 1-3/8″ (34.6mm) hole1.

    The trade size system was developed to simplify conduit selection and ensure compatibility between components. However, it can be confusing for those unfamiliar with industry standards3.

    Understanding this distinction is crucial for electricians and DIY enthusiasts when selecting the appropriate conduit size and drilling the correct hole size for their specific installation needs. The hole size is typically larger than the trade size to accommodate the fittings and connectors used with the conduit14.

    the hole sizes mentioned for electrical conduit also apply to knockouts needed for connectors and other fittings12. These standardized sizes ensure compatibility between conduits, connectors, and electrical boxes. For example:

    1. A 1/2″ trade size conduit or connector requires a 7/8″ (22.5mm) knockout or hole.
    2. A 1″ trade size conduit or connector needs a 1-3/8″ (34.6mm) knockout or hole.
    3. A 1-1/4″ trade size conduit or connector fits into a 1-3/4″ (43.2mm) knockout or hole.

    This standardization allows electricians to use the same knockout sizes for both conduits and their corresponding connectors, simplifying installation and ensuring proper fit. When working with electrical panels or boxes, the knockout sizes are designed to accommodate these standard trade sizes for conduits and connectors34.

  • Furnace large custom duct collars for large ductboard return

    According to North Carolina building codes, there are specific requirements for constructing duct collars when building a large ductboard supply duct into the furnace:

    1. All connections, including the duct collar, must be sealed with water-based duct mastic1. This is critical for meeting the new North Carolina Energy Conservation Code (NCECC) requirements.
    2. Tape can be used during installation, but should not be relied upon as the primary method of air sealing ductwork1. Mastic should be applied over the tape to ensure airtightness.
    3. The duct collar should be properly sized and well-sealed where it meets the air handler1. This is particularly important due to the large size of plenums, as poor connections at the air handler can lead to significant leaks.
    4. When connecting the ductboard to metal components like the furnace, a metal collar or sleeve should be used to ensure a secure and airtight connection4.
    5. The duct collar must be constructed to meet the pressure class requirements of the system4. Each size in a pressure class has minimum specifications for joints and reinforcements.
    6. Proper support for the duct collar and adjacent ductwork is required. Metal straps with a minimum width of 1 inch (25 mm) and equivalent to or heavier gauge than the duct material should be used for support8.
    7. The duct collar should be designed to allow for proper airflow and minimize pressure drop in the system4.

    Remember to consult the specific North Carolina Mechanical Code and SMACNA guidelines for detailed requirements and best practices when constructing duct collars and connections.

  • Main duct furnace collar examples

  • Red Devil 0841DX F-Seal 181 Fiber Reinforced Water Based Duct Sealant -It is better than regular water based mastic

    Red Devil 0841DX F-Seal 181 Fiber Reinforced Water Based Duct Sealant is indeed considered a duct mastic and offers several advantages over regular water-based mastic:

    1. Fiber reinforcement: F-Seal 181 contains fibers that enhance its sealing strength and workability, making it more durable and effective for sealing duct joints12.
    2. UL listings: It is UL 181A-M and B-M listed, indicating it meets strict standards for use with both rigid fiberglass ductwork and flexible air ducts14.
    3. Versatility: F-Seal 181 is suitable for various HVAC applications, including metal ductwork, fiberglass duct board, and flex duct, both indoors and outdoors24.
    4. Performance: It exceeds all SMACNA pressure and sealing classes, providing excellent adhesion and flexibility14.
    5. Additional benefits: F-Seal 181 offers mold and mildew resistance, low VOC content, and contributes to LEED EQ Credit 4.124.

    While regular water-based mastic can be effective, F-Seal 181’s fiber reinforcement and specific formulation for HVAC applications make it a superior choice for many duct sealing tasks. Its fast drying time, excellent adhesion, and ability to seal high, medium, and low-pressure HVAC duct systems further set it apart from standard mastics45

    Red Devil 0841DX F-Seal 181 Fiber Reinforced Water Based Duct Sealant offers several environmental benefits:

    1. Low VOC content: The product has low volatile organic compound emissions, which contributes to better indoor air quality68.
    2. LEED compliance: It is LEED EQ 4.1 compliant, supporting green building practices and sustainability initiatives8.
    3. Water-based formula: Being water-based, it reduces the use of harmful solvents and is more environmentally friendly compared to solvent-based alternatives6.
    4. Improved energy efficiency: By effectively sealing HVAC duct systems, it helps reduce energy waste and improves overall system efficiency6.
    5. Durability: The fiber-reinforced formula provides long-lasting performance, reducing the need for frequent reapplication and minimizing waste6.
    6. Versatility: It can be used on various duct materials, including metal, fiberglass duct board, and flex duct, both indoors and outdoors, reducing the need for multiple specialized products68.
    7. Mold and mildew resistance: This feature helps maintain a healthier indoor environment and extends the life of the ductwork1.

    These environmental benefits align with Red Devil’s commitment to meeting product demands while helping to preserve the environment and complying with environmental health and safety regulations1.