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Old 05-01-2012, 10:04 PM   #1
Sep 2010
Lake jackson, TX
Posts: 23
Liked 1 Times on 1 Posts

what size hole to drill for 1/2 fittings for my converted beer kegs. I have 1/2 inch fittings for my SS keg and plastic mash tun

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Old 05-01-2012, 10:10 PM   #2
stixobutta's Avatar
Nov 2011
Kittery, Me
Posts: 70
Liked 6 Times on 5 Posts

Standard 1/2" pipe OD is .840". So if your drilling a through hole to attach fitting then a 7/8 hole .875" should do.

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Old 05-01-2012, 10:10 PM   #3
Oct 2011
Greeneville, TN
Posts: 243
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A 1/32 less than 7/8 works for me. But it really depends on you fitting. Threads seems to vary by a 32nd or so. I like to keep it tight as possible. So I drill a little, then try it, then drill a touch more until I can get it where it almost threads in.

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Old 05-01-2012, 10:18 PM   #4
Bernie Brewer
Grouchy Old Fart
Bernie Brewer's Avatar
Feb 2006
Eldorado, WI
Posts: 7,507
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Get yourself a 7/8" holesaw and go to town.
I like to squeeze the nickle until the buffalo craps-mt rob

"Why don't we get drunk and screw?" Jimmy Buffett

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Old 05-01-2012, 10:36 PM   #5
Mar 2011
Fraser, MI
Posts: 531
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7/8" will work great.
I did 13/16" and the holes are so tight I couldn't put tape on the threads until the fitting was already through the hole.
No leaks though

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Old 05-01-2012, 10:53 PM   #6
Dec 2011
Madison, WI
Posts: 821
Liked 19 Times on 19 Posts

Wait till you get your couplings. The outside diameter can vary quite a bit by manufacturer, batch, etc. A step bit can allow you some flexibility.

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Old 05-02-2012, 12:24 AM   #7
Dec 2010
VA Beach, VA
Posts: 886
Liked 71 Times on 52 Posts

Yes - definitely wait. I'd had couplings from one manufacturer to another that have massive variances.

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