Okay, this is a common frustration! Here's a breakdown of what's likely happening and some potential solutions, keeping in mind safety is paramount and local electrical codes must be followed. If you are not comfortable working with electricity, please hire a qualified electrician.Understanding the Problem



Box Types

You're dealing with a standard "device box" which is typically either metal (like your Raco) or plastic. Metal boxes are required when using armored cable to provide grounding, which is the right approach for an island.

USB Receptacle Size Variation

USB receptacles, especially those with the charging features built-in, can be slightly larger than a standard duplex receptacle. This is due to the internal circuitry required for the USB charging.

Tolerance Stack-up

Even if the USB receptacle is slightly larger, the combination of the box's internal dimensions and any potential tolerances in the receptacle's manufacturing can make it a tight fit, or prevent it from fitting entirely.

Slip Fit (Original Receptacle)

The "slip fit" receptacle likely wasn't secured as well as it should have been. Standard receptacles use screws to tighten to the box. It also likely was a simple outlet, with no USB receptacle.

Solutions (in order of ease/preference)


Try a Different Brand/Model of USB Receptacle

This is often the easiest and best first step. There's no single "standard" size for USB receptacles. Different manufacturers have slightly different dimensions. Go to your local electrical supply house and ask about USB receptacles that are known to be more compact. Take a look at the ones on display. Carefully compare the dimensions of several different brands. Online reviews and product specifications (if available) might give you an idea of overall dimensions.2.

"Shaving" the Plastic (Use with Extreme Caution and Only if Absolutely Necessary - Disconnect Power!)



WARNING

This is a potentially dangerous approach, and I only list it because it's sometimes possible.

ONLY do this if the interference is very, very minimal (like less than 1/32 of an inch), and ONLY on the plastic body of the USB receptacle, AWAY from any electrical components. You are responsible for determining if this approach is correct. Carefully inspect the USB receptacle. Look for any small plastic "fins" or ridges on the sides of the plastic housing that are interfering with the box. Using a sharp utility knife or a small file, carefully remove ONLY the interfering plastic. Be extremely cautious not to cut into any wires or electrical components. Disconnect the power at the breaker box. Test-fit frequently. I HIGHLY RECOMMEND AGAINST THIS UNLESS YOU ARE ABSOLUTELY SURE YOU KNOW WHAT YOU'RE DOING AND THE AMOUNT OF MATERIAL TO REMOVE IS TINY. It can compromise the integrity of the receptacle and could create a safety hazard.3. Modify the Metal Box (Not Recommended, Potentially Dangerous)

Don't. Modifying a metal electrical box is generally a bad idea. It can compromise its structural integrity and, more importantly, its ability to ground properly. You could potentially damage the box in a way that makes it unsafe.4.

Using a Deeper Metal Device Box

While you don't want a double-gang, consider replacing the existing Raco box with a deeper single-gang metal device box. A deeper box gives you more room to work with, which can help with the wiring and potentially accommodate a slightly larger receptacle. Make sure the new box is UL-listed and compatible with your armored cable.5.

"Old Work" Boxes (Potentially Problematic)

"Old work" boxes (also called "remodel" boxes) are designed to be installed in existing walls. They have "wings" or "ears" that clamp onto the back of the wall.

Problem

They often require a larger cutout in the wall to install, and they may not be as structurally sound as a standard device box. You may still have size limitations that will not allow you to install the USB receptacle,

Armored Cable Issue

They are often plastic, so you cannot connect armored cable to a plastic box.6.

Use a "Smart Plug" (Less Desirable, but Simple)

If all else fails, you could use a standard receptacle and plug in a "smart plug" that has USB charging ports. This gives you the charging functionality without having to replace the receptacle. These are relatively inexpensive and widely available.

Important Considerations



Electrical Codes

Always follow local electrical codes. This is not just about safety; it's also about ensuring your work is up to code for insurance purposes.

Grounding

Proper grounding is critical. Ensure that the metal box is properly grounded to the ground wire in your armored cable.

Wire Connections

Make sure all wire connections are tight and secure, using wire nuts of the correct size.*

Overfilling the Box

Don't overfill the electrical box with wires. This can make it difficult to install the receptacle and can create a fire hazard. The NEC (National Electrical Code) has specific guidelines on box fill.

Before You Start


Turn off the power at the breaker box. Verify it is off using a non-contact voltage tester before touching any wires.2. Take a picture of the existing wiring before you disconnect anything. This will help you remember how the wires were connected.3. Use appropriate safety gear: Wear safety glasses and insulated gloves.Good luck with your project! Take your time, be careful, and if you're unsure about anything, consult with a qualified electrician. Flag for review