Best way to drill hole in top plate for conduit. (Revisited)

Been trying to drill through that top plate for my 2 inch conduit. For
some reason, it looks extremely deep. Like it is 3 or 4 2x4's thick. I
used a spade bit with a long extension just to get a small hole. I
will have to install the conduit in small sections with pvc couplers
because of ceiling height. (No room to drop a 10 foot section in
without hitting the roof). So the hole will need to be the diameter of
the coupler which is about 2 3/4. Also, where i need to put the hole
is right beside 2 electric wires that drop down this wall into the
panel.
What is the best, easiest way to cut this hole and to ensure it works?
Reply to
stryped
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That's not uncommon. Some walls will have two 2x4s for the top plate, then that'll be capped off with a 2x6 to act as a sheetrock nailer board. That setup can give you a good 4-1/2" to 4-3/4" chuck of wood to drill through.
Reply to
Rich.
SO how do I get a 2 3/4 inch hole through that?
Reply to
stryped
If you have a 1.5- 2" deep hole saw you drill one, Take out the plug, drill the next etc. Those are the white ones that screw on the mandrel
Reply to
gfretwell
Hole saw of the appropriate diameter. With an extension if needed. That's your best bet if you've already started a smaller hole. Other type of bits need the center pilot bit to keep a straight track, but one a hole saw gets started, it's sides will keep in in line. You can also use it to one side or the other of the hole you've already drilled. That might be important to miss the existing wiring.
I'm not picturing what is above this top plate. A roof? How much room do you have to work with once the conduit comes out the other side of the top plate? Enough room to accommodate a bend?
Reply to
Paul Hovnanian P.E.
That or get one of these bits if you have a strong 1/2" drill. TIP: when using these kind of bits, keep pulling them out often to clean the wood chip out of the hole. Failure to do so will jamb the bit in the hole.
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Reply to
Rich.
Above is the slant to my roof. My floor joists for the attic are between the top plate.
Reply to
stryped
Your conduit is oversized. Put a 2" - 1" reducing bushing on the LB and run 1" down to the panel. RE
Reply to
Ryan Evans
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Is one inch enough for 3 # 3 wires and a #6 ground? I was thinking like you last night and bought a 1 and 1/2 inch conduit. I figured I would need to get a 2 1/4 inch hole saw to cut the diameter of the couplings I need to piece the pipe together. WIll this size hole affect the structural ingetrity of the 2x4? I dont think this is a load bearing wall. It runs parrallel with the joists in the attic. Also, the bottom of the wall rests on the concrete garage floor, not the block foundation like the rest of the house.
I want to be safe just in case though.
Also, because it is hard for me to get the hole centered becasue of other wires I bought a "meter offset" to put at the panel attachment point. I assume this is acceptable?
Reply to
stryped
Nope! 3 #3s and a #8 will fit in 1" conduit, but for 3 #3s and a #6 you need to use 1-1/4" conduit.
Reply to
Rich.
hole that is too big.
Reply to
F Murtz
Or glue a hunk of wood in the existing hole to provide some wood to guide the bit.
Reply to
James Sweet

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