Is making a knockout bigger allowable?

I am removing my #4 romex feeding my sub panel due to suggestions on here. When I removed the main panel end, I discovered the knockout in
only one inch and I planned on installing 1 1/4 inch conduit. Can I just drill out to the proper size with a hole saw? The other knockouts are difficult if not impossible to get to.
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stryped wrote:

Yes, normally you use a punch for this. It has a cutter and die that are pulled together by cranking down a bolt and it slices a nice neat hole.
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Yes you can make it bigger. To use a hole saw you'll need a couple of C-clamps and a piece of wood. Clamp the wood inside the panel covering the existing knockout hole. Having the wood there gives the hole saw pilot bit a place to hold onto.
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wrote:

Or use a proper Greenlee punch.          ...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
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