How much pushing is needed in a box?

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NeilG

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I've wired a few electrical boxes, but always was curious; how much pushing is acceptable to attache the fixture into the box? I just finished wiring a GFCI into a 4 inch box with a raised cover, and 3 Romex cables entering the box. Not matter what I did, I had to push a bit to get the cover with the GFCI attached to it to close. Maybe the last 3/4 of an inch was pretty springy. The pros on Youtube make it look so easy and neat.
 

Snoonyb

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There is a methodology, stranded is more flexible that solid conductors, size of the conductors, rear or side mounted. Often "S" curves taking up the slack.
 

afjes_2016

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It isn't really how much "pushing" is needed/allowed more so than "box fill" max capacity. You can check "box fill" chart (interactive) here.

Using solid conductors, especially 12 gauge will be a bit of a challenge. Using a deep 4x4 metal box and a raised cover will help. Even "pushing" conductors into the box when the box is not that filled can create a challenge. Folding the conductors back as you push the receptacle into the box does help. There will be some resistance which is normal.
 

bud16415

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The above advice is good and I might add a few tidbits.



First is how much extra wire to leave. I have worked on homes with both extremes. I had one older home I cursed the previous owner as everything he did there was only about an inch of wire just enough to get it out of the box and a screwdriver on the screws. Then I have seen some where there was 18” of wire coiled up. Those are easy you just shorten it up.



Secondly is the wires that are in the box that can be dressed up and put to the back prior to the main item that is in the box. This is the difference in running a pigtail to an outlet rather than trying to make the running connection on the spare screw of the outlet. With a pigtail you can make that setup and then fold the wires all the way to the back of the box neatly. I have a pair of duck bill pliers I like to use for pushing and seating the wires deep in the box folding the wires all the same way rather than a glob of wires all fighting each other. Then the main wires running to the switch or outlet do as described above and get a S bend going where they will all bend together and lay back in the box.



I personally worry a little when one takes a too much push to get it in as I picture down the road that force causing a wire to come loose off a screw or something.

I would say my rule of thumb is if I can shove it all in by hand it is fine, but if I need to use the screws to winch it down I take it all out and work on cleaning it up and try again.
 

NeilG

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Thanks, very helpful. It was the pigtails to the GFCI that were giving the resistance. I'll go back in and see if I can improve things.
 
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