Update on conduit into sub panel.

I started to drill a hole with my 2 1/2 inch hole saw last night into the top plate. I realized it is probably a double 2x4 top plate. Can I
just take a saws all and after drilling a hole completely through with a long drill bit use the saw to cut a 2.5 inch x 4 inch square or so in the top plate so I can fish the conduit down?
I also noticed that the people that put my small heat pump/air conditioning unit for my bonus room went through the top plate in about the same place I need to drill. They ran a 12-2 and 10- 2 wire into the wall. (No conduit). Inside that cavity is the back of a shower enclosure. When I looked, the back of the shower enclosure has a metal strip attached to it all the way down with scres pointing out. (I guess for the enclosure to attache to a wall or somethign.). They are not sticking into anything. I am wondering while I am doing all this if I should run those 2 cables in conduit to keep them away from the screws or am I worryign over nothing?
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stryped wrote:

Use a Forstner bit, they hog out the wood so you don't run into the depth problem you do with hole saws. Make sure you've got a good grip on the drill though.
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You can use the hole saw to cut through the first two by four of the top plate. It is not usually doubled but if it is then use a chisel to break up the wooden plug if it does not come out readily. Once you pull the wood slug out of the first plate you can then drill the second if you find one. When using hole saws you should always use the side handle on the drill so that if it hangs up in the work it will not break your wrist. -- Tom Horne
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And remember to let go of the drill completely if you hit a nail or such and it seriously does a "tornado". Once you let go of the trigger and handles, it will wrap up the power cord a little and you can unwind it after it's stopped.
That's better than explaining to the ER physicians how you broke the wrist bones...
FBt
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Or reducing the power/rpm of the drill, especially if you have a powerful one, like here in EU (1200 watts).
--
Tzortzakakis Dimitrios
major in electrical engineering
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Tzortzakakis Dimitrios wrote:

You need a lot of power to run one of those big Forstner bits, normally they're used with big half inch drills which I'm guessing are in that power range. Anything that will hog out wood like that will hurt you if things get out of hand.
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Guilty as charged. This just happened to me about 10 days ago. I was holesawing through siding to install a box for an exterior light and WHAM...the holesaw grabbed the wood and the drill took my wrist for the roll of death. It still hurts to use it.
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