Drilling through cinderblock

Old 04-12-17, 08:07 AM
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Drilling through cinderblock

I need to put a piece of PVC through my basement wall to the outside. It is standard cinder block and I have found core drills on Amazon.

My question is if I am using 1.2" PVC will a 2" drill bit work as I know the OD of pvc is larger, 1-7/8s I believe?

There is a piece of pvc carrying AC pipes to the outside and it looks like they drilled the hole larger than the pvc then just filled it with silicon or some type of sealant.

Thanks for your help
Old 04-12-17, 09:19 AM
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Deep masonry core drills can be expensive and they need a larger drill to power them. I usually use a normal masonry bit and drill a series of smaller holes in a circle to make the size hole I need. A 12" long 3/8" or 1/2" bit is relatively inexpensive and most hammer drills can power it.
Old 04-12-17, 10:38 AM
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And be sure to drill between the webs to make it easier.
Old 04-12-17, 10:40 AM
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Ya, if you drill into the web it makes it all but impossible
I also drill a series of little holes and then hammer/chisel it from there. Mortar or caulk will fix any discrepancies.
Old 04-12-17, 11:13 AM
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If you decide to go with the one large drill bit, first drill a small pilot hole all the way through. Then use the large bit to drill half way. Then Go to the other side and do the same. This will prevent blow-out.
Old 04-13-17, 06:18 AM
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Thank you for all your suggestions

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