How do you knock a hole in a plastic electrical box?

Asked By: Becky Ochsenmeier | Last Updated: 2nd April, 2020
Category: hobbies and interests woodworking
4.7/5 (2,082 Views . 22 Votes)
The knockouts can be removed with a flat-head screwdriver in 2 simple steps:
  1. Place the flat-head screwdriver into the slot of the knockout that is to be removed.
  2. Hit the end of the screwdriver to shear the knockout and remove the rest of the knockout by hand if necessary.

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Beside this, how do you punch a hole in a plastic electrical box?

The knockouts can be removed with a flat-head screwdriver in 2 simple steps:

  1. Place the flat-head screwdriver into the slot of the knockout that is to be removed.
  2. Hit the end of the screwdriver to shear the knockout and remove the rest of the knockout by hand if necessary.

Likewise, how do you cut a hole in a plastic project box? 4 Answers

  1. Cover the surface of the plastic with masking tape, so you don't scratch it.
  2. Mark out the rectangle you want to cut out.
  3. Using a very sharp knife, score the edges of the rectangle against the side of a metal ruler.
  4. Cut deeper and deeper grooves with the knife, until you can eventually push out the rectangle.

Also asked, how do you knock out a hole in an electrical panel?

To remove a knockout, position the tip of a regular, blade-tip screwdriver just inside the edge, on the side opposite the attachment points. That ought to partially dislodge the knockout, allowing you to remove it the rest of the way by twisting back and forth until the attachment points snap.

How do you fill missing knockouts in electrical box?

How to fix a missing knockout plug. First, determine the size of the missing knockout hole and subtract 3/8" to figure out what size knockout plug you'll need. For example, if you have a 7/8" hole, you'll need a 1/2" knockout plug. Next, go buy some knockout plugs.

36 Related Question Answers Found

Can you screw an electrical box to a stud?

Nail-on plastic electrical boxes are affordable and easy to use. Electrical boxes that are mounted to wall studs during new construction must be positioned so that, when drywall is added, the face of the box will be flush with (or very slightly inset from) the wall's surface.

What is a KO seal?

Knockout Seals (2-Pack) are designed to cover exposed knockout holes in steel outlet boxes and other metal enclosures. These steel seals are zinc-plated for corrosion resistance.

Do I need to ground light switch?

If you are replacing a switch a ground is not required, as per the above exception. However, if you're installing a switch; replacement or otherwise, into a metal box that is grounded. The switch will be ground via the devices yoke and mounting screws. So if the metal box is grounded, the switch is also grounded.

What is knockout size?

A knockout for 1/2" conduit is 7/8", but the outside diameter of a 1/2" EMT fitting is about 3/4". 3/4" knockout is 1-3/32" (close enough to 1-1/8), and O.D. of 3/4" fitting is roughly 1".

What is a knockout panel?


A knockout panel is a design feature that is built during the construction of a building. It allows a door or passageway to be installed between two units, while having only minimal impact of the structural function of the wall. A doorway can also be removed, by reinserting the wall panel to re-create the smaller unit.

How do you use knockout?

How to Use a Knockout Punch Set
  1. Drill a hole through the material, using a drill and metal-cutting bit.
  2. Fit the appropriate size of die onto the draw stud, then insert the draw stud into the pilot hole.
  3. Thread the desired size of punch onto the draw stud and hand-tighten it to the backside of the material.

What is a wire bushing?

Bushings are used to protect both wires and the machines and surfaces that they pass through. To protect wires, bushings insulate openings for the wires to pass through so they won't be damaged in any way. This insulation also prevents short circuits and damage to machinery by keeping wires separated from each other.

How do I remove conduit from junction box?

How to Repair and Remove Conduit for Electric Wires
  1. Step 1: Shut Off the Electricity Flow.
  2. Step 2: Disconnect the Wires Near the Damage.
  3. Step 3: Pull One End of the Wires Out of the Conduit.
  4. Step 4: Unscrew or Use Pliers to Remove Conduit Supports.
  5. Step 5: Unscrew the Electrical Conduit Fittings.
  6. Step 6: Measurements.
  7. Step 7: Cut a Part of Conduit Tubing.

What systems require grounding?

Typical systems permitted, but not required, to be grounded include 240V, three-phase, 3-wire and 480V, three-phase, 3-wire, delta-connected systems.

How do you cut a rectangular hole in metal?


Use side cutters to damage the metal between the holes, then man-handle the metal out with a screwdriver and / or hammer. Clamp your panel upright in a vice, and use a coarse file to square up the hole. Option 2. Drill a large hole at two opposite corners, and use a small saw blade to cut each edge.

How do you cut an ABS plastic box?

Cutting Holes in an ABS Plastic Project Box
  1. Using a 1/16″ drill bit, I cut holes into each of the corners.
  2. I then used a pencil to draw lines between the corners to find the center point of the hole.
  3. With the center located, I drilled out a large enough hole in the center to allow a saw blade in.
  4. Using an air saw, I cut from the center hole to each corner.

How do you cut a square hole in plexiglass?

Drilling and Cutting
  1. Drill pilot holes at the corners of the square. Avoid drilling the holes too close to the corners and make sure the edges of the pilot holes do not go beyond the outline drawn.
  2. Attach the fine-toothed saw blade to the jigsaw.

Should I use plastic or metal electrical boxes?

Plastic boxes don't use metal cable clamps and do not provide the required grounding path. Metal electrical boxes are primarily used with metal-sheathed or "BX" wiring. However, they can also be used with Romex or NM wiring if desired. Most new residential electrical systems use Romex and plastic boxes.

Where does the ground wire go in a plastic box?

Because they are plastic, there is no need to attach a ground wire to it. Since it is made of a non-conductive material, switches and outlets cannot short out if they touch the side of the box. Plastic boxes usually come with tapped screw holes for easy attachment of switches and outlets.

Do all light fixtures need a junction box?


Not all light fixtures require junction boxes because some have their own. When installing one of these fixtures, it's okay to feed the wire straight into the terminal box, make connections and screw the box closed. When feeding a cable into a fixture box, it's important to secure it with the clamp in the box.

How many wires can be in a junction box?

Metal and other material boxs fill is based on the box size in cubic inches and the required space for each conductor size. #14 wire require 2 cubic inches each. All the grounds together count as 1 wire. In your case, 6 cables with 2 wires each plus a ground requires a box that is big enough for 13 #14 wires.

What do you do with the ground wire in a junction box?

The junction box will have a green screw. Screw the ground wire to this as it connects to a tapped threaded hole on the back side of the junction box. If there's no screw, there should be a grounding clip. This secures the ground wire to the edge of the metal junction box.