[miamicuse]

I removed the cover of a 2 gang electrical box to replace some switches. The metal box inside is a 2 gang box, but it seems to have an extra pair of mounting tabs.


Most of the 2G metal junction boxes have mounting tabs at opposite corners to mount mud rings. 2G switch boxes have two pairs along two edges for direct mounting of switches or receptacles. Yet this box has two tabs at the corners, and next to those each tab there is an additional tab.


Here is a picture of the box.

As you can see, there is a flat 2G mud ring over it, secured by screws into the corner tabs. The last picture shows that clearly.


Yet there is an additional tab below the upper right corner, and above the lower left corner. What are those for?

With those tabs in the way, I cannot use a bulkier dimmer switch.

 

[surferdude2]

I'd apply some Dumore or other hand grinder to it. I can't say I've ever seen anything like that so perhaps someone got a little too creative. Replacing it will be advised if you can't grind the obstructions away and still have a safe switch box.

 

[rjniles]

That looks like a flat mud ring on a 4" box.

 

[miamicuse]

I'd apply some Dumore or other hand grinder to it. I can't say I've ever seen anything like that so perhaps someone got a little too creative. Replacing it will be advised if you can't grind the obstructions away and still have a safe switch box.

I can grind it out pretty easily with a dremel I think. I just didn't want to do it without finding out why the tabs are there. I have never seen a box with tabs in those positions in addition to the corner tabs.

 

[miamicuse]

That looks like a flat mud ring on a 4" box.

Yes it is. But a standard 4" box will have two corner tabs like this.

and when you use a flat mud ring (or any 2G mud ring) they will be secured to the corner tabs with two screws. I can see the two screws in the corners of this box.

so my question was, why are there two ADDITIONAL TABS adjacent to the corner tabs, is this a special purpose 4" box?

These two tabs are in the way if I want to mount a more boxy switch.

 

[Jim Port]

Older boxes sometimes had two sets of screw tabs. Just remove them.