Pulling branch circuit to electric panel

[snakevargas]

I have a new branch circuit that I need to pull from the attic to the panel. The panel is flush mounted in the wall. Routing it through the attic, drilling through the top plate, that's not a problem.

Where I run into an issue is actually getting the wire into one of those little knockouts on the top of the panel. A fish tape isn't going to be so lucky as to just go through that little hole. My plan is to temporarily cut out a section of drywall right above the panel. I figured I'd ask here first, just in case there's some clever trick I'm missing as I'm getting a little tired of cutting up and patching drywall.

 

[apostolakisl]

Is there insulation in the wall?  If so, good luck.
 
But the trick I use is a fishing line (actual fishing line, not fish tape) with a nut tied to the end.  Dangle that through the hole in the top plate into the wall space.  Use a magnet on a stick (get them at auto-part store for like $2) and stick it up into the hole on the top of the panel and extend it (they are made the same as extendable antennas).  Then swing stuff around until you manage to get the nut to stick to the magnet.  Your challenge here would potentially be the myriad of other wires in the wall.  Also don't accidentally touch the main feed lugs at the top of the panel.

 

[Neurorad]

When I had a sub panel installed by an electrician, he showed me a half inch gap between the top of the box and the drywall. The gap is covered by the cover. Not sure if every box is installed like that.

 

[snakevargas]

In my panel, the tape on the drywall slightly overlaps the top of the panel. No gap.


I went out this morning to use my inspection scope on the wall (I usually do this before drilling, just to be safe), and I realized I have the perfect tool for this! The inspection scope has a 6' length with extension, it's well lit, and can make it all the way up to the top of the wall. All I'll need to do carefully navigate the scope up through the generous 1.25" hole I drilled in the top plate and use the scope to pull a line back down. My habit of buying every obscure tool I could possibly use will finally pay off!


After 30 minutes of trying to line that damn scope up with that damn hole, I gave up and just cut out the drywall. It just wasn't in a mood to cooperate. The scope would always end up about an inch over from the hole. I'm guessing existing wires in the wall were interfering.

In addition to my wire, I added an empty conduit for future use. The mud is now drying on the wall.

@Lou: Thanks for the tip, I'll keep that in mind!

 

[apostolakisl]

In my panel, the tape on the drywall slightly overlaps the top of the panel. No gap.


I went out this morning to use my inspection scope on the wall (I usually do this before drilling, just to be safe), and I realized I have the perfect tool for this! The inspection scope has a 6' length with extension, it's well lit, and can make it all the way up to the top of the wall. All I'll need to do carefully navigate the scope up through the generous 1.25" hole I drilled in the top plate and use the scope to pull a line back down. My habit of buying every obscure tool I could possibly use will finally pay off!


After 30 minutes of trying to line that damn scope up with that damn hole, I gave up and just cut out the drywall. It just wasn't in a mood to cooperate. The scope would always end up about an inch over from the hole. I'm guessing existing wires in the wall were interfering.

In addition to my wire, I added an empty conduit for future use. The mud is now drying on the wall.

@Lou: Thanks for the tip, I'll keep that in mind!

 
I used that trick to fish a wire 15 feet down a chase from a 1/2 inch hole at the top and out a 1/2 inch hole at the bottom.

 

[snakevargas]

I used that trick to fish a wire 15 feet down a chase from a 1/2 inch hole at the top and out a 1/2 inch hole at the bottom.

You are a more patient man than I!

I do like the trick, and I may use it sometime. It was exactly the sort of thing I was looking for. I take it the trick necessarily requires two people? or can you somehow solo it?

 

[apostolakisl]

I did it with two people over a cell phone.  You could do it with one person but the running back and forth thing gets old real fast, especially when it involves crawling in and out of an attic.
 
But that part only took my buddy and I about 2 or 3 minutes.  the hard part was drilling the holes (6 inches of concrete slab at both ends).  Even with a commercial grade Hilte hammer drill.  The hole from the bottom drilling over the head was challenging.
 
And now that I think of it, the holes were 7/8 not 1/2 inch.  I pulled smurf tube through them.

 

[tmbrown97]

I'm with snakevargas on this one - when I needed to add a couple new circuits to my panel, the only logical thing I could come up with was to open the drywall to get full access inside the wall.  My patience level is a lot lower than my drywall repair budget.