Screw heads: Phillips/Slotted vs ECX

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In summary, newer electrical switches and receptacles in the USA are held in place by ECX screws, which do not work well with traditional Phillips or slotted screwdrivers. These screws can be driven with a Phillips or slotted bit, but not as effectively. The ECX screws are similar to a Pozidriv head, which was introduced to overcome the issues with Phillips screws. However, it can be difficult to find a bit that fits the ECX screws in local hardware stores. Alternatively, some people suggest using a square drive bit, which may work better than a Phillips or slotted bit. However, it may not work with all types of ECX screws. Overall, it seems that finding the right driver bit for these types of
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Stephen Tashi
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Why have ECX style screw heads become standard on electrical switches and receptacles?
(In the USA) recently purchased swtiches and receptacles are held to electric boxes with screws that don't work well with either Phillips or slotted screwdrivers. ( e.g. https://www.homedepot.com/p/Leviton...RCH=REC-_-pipsem-_-301447034-_-100026991-_-N& ) I understand this type of screw head is called "ECX". When did this type of screw become standard? - and why?

Electrical switches once came with screws that were a compromise between Phillips and slotted and did work with either type of screwdriver.

Although the ECX screws can be driven in a clumsy way with a Phillips or slotted bit, neither of those bit types really fits them.
 
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I'm sure Home Depot will sell you a new tool.
 
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ECX does OK with phillips but also works with a square drive. The square drive works very well and I must admit is better than phillips IMHO. So get a few square bits (I think #2 is the one of choice...provbably 2mm)

Correction: apparently ECX is not the same as a combination., But I think a normal square bit will drive them. I do like the square better than phillips in general. Progress!
 
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My electrician friend that I occasionally help has half chewed my butt because I didn't have a square drive when working in a panel or making up connections. Yes we're still on good terms over it. Lol
 
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My fastener of choice is the stainless steel #2 square head deck screw. My world would be far less securely screwed without it.
 
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From your image, the ECX head looks more akin to a Pozidriv head than to a Phillips head. Does a Pozidriv screwdriver fit it?

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As I recall, Phillips were introduced in the US for automated manufacturing - the driver was supposed to self align. In reality, the flanks of the driver are slightly tapered and the driver easily climbs out of the "slot", especially when using a manual driver. The flanks are quite thin. I curse whenever I buy something today which uses Phillips screw heads and I keep my Phillips drivers well separated from my Posidriv drivers so I don't use them by mistake.

Pozidriv was then introduced by GKN, a British company, to overcome this problem. The flanks of the driver are thicker and are not tapered - they are square to the faces in the "slot" making it much less likely that the driver climbs out of the slot and much less likely for the screw head to become mangled. Pozidriv screw heads have "tick marks" between the slots identifying them as different from Phillips. A Phillips driver will go into a Pozidrive slot of similar size and likley damage the slot. A Pozidriv driver's blades are too wide to enter a similarly sized Philips slot. They may be less common in the US.

Alternatively, is it a Phillips/square screw drive, also known as the Quadrex or Pozisquare?

I would be tempted to use a square drive - the slots look pretty poor.

Edit: I have just tripped across Screwdriver Bit Head Design – Effect of Phillips, Straight, and a Hybrid Design on Torque, Axial Force, and Effort Ratio

Edit 2: Posidriv corrected to Pozidriv
 
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Frodo said:
From your image, the ECX head looks more akin to a Posidriv head than to a Phillips head. Does a Posidriv screwdriver fit it?
In my extensive collection of screwdriver bits, I havn't found a bit that fits it. Whether any of my bits is officially a Posidrive, I don't know. (Phillips/square bits that fit deck screws don't work. I think ECX is a proprietary design made by the Milwaukee company and I haven't seen it for sale in local stores. ) I agree that, from photos of a Posidrive bit, that bit is a good candidate. However, if that's the answer, I find it strange that local hardware stores don't sell packs of Posidrive bits for power tools - because installing electric outlets and switches is such a common task.

When it comes to finding driver bits of various sorts, it's easy to find the interchangeable kind that rely on magnetism or shallow notches to hole them in tools. But these bits are inconvenient because they tend to stick in the heads of screws and pull out of the tool. The convenient type of bit has prounounced narrowing of the shaft that locks into mechanism of drivers. Packs of bits like this for T25 Torx and Phillips are easy to find in stores.

I would be tempted to use a square drive - the slots look pretty poor.
I tried a small square drive bit on the screws for receptacles and it worked a little better than a slotted bit or a Phillips. However, I couldn't find a square bit that worked with the similar shaped screwheads on a the bracket for a ceiling fan that I was installing last night.
 

Related to Screw heads: Phillips/Slotted vs ECX

1. What is the difference between Phillips and Slotted screw heads?

Phillips and Slotted screw heads are two different types of screw heads. The main difference between them is the shape of the cross-section. Phillips screw heads have a cross-shaped indentation, while Slotted screw heads have a single straight line indentation.

2. Which type of screw head is more commonly used?

Phillips screw heads are more commonly used than Slotted screw heads. This is because Phillips screw heads are designed to prevent the screwdriver from slipping out of the screw head, making it easier to drive the screw into place.

3. What is an ECX screw head?

ECX (External Torx Plus) screw heads are a newer type of screw head that combines the features of both Phillips and Slotted screw heads. They have a star-shaped indentation with a small Phillips cross in the center. This design allows for better torque transfer and prevents cam-out, making it ideal for high-torque applications.

4. Which type of screw head is better for precision work?

Slotted screw heads are better for precision work as they allow for more control and finer adjustments. However, they are also more prone to slipping and stripping, so it is important to use the correct size and type of screwdriver when working with Slotted screw heads.

5. Can Phillips and Slotted screwdrivers be used interchangeably?

No, Phillips and Slotted screwdrivers are not interchangeable. Using the wrong type of screwdriver can result in damage to the screw head, making it difficult to remove or drive the screw. It is important to use the correct type and size of screwdriver for the corresponding screw head to ensure a secure and successful installation.

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