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Re: Drill size for 1/8" NPT tap?

To: "Tony Clark" <lotus.tony@airmail.net>
Subject: Re: Drill size for 1/8" NPT tap?
From: Bob Hamilton <hamilton@cast.navnet.net>
Date: Fri, 18 Dec 1998 19:56:30 -0400
Tony,

        Don't you mean "NPT"? (not NPT) National Pipe Thread which is tapered.

Later,
Bob


At 05:29 PM 12/18/98 -0600, you wrote:
>
>
>-----Original Message-----
>From: Ken Landaiche
>
>
>>What do you mean by "respect the taper"? I have tapped straight holes,
>>so I have the basic idea. But I never did a tapered hole.
>>
>>Ken Landaiche
>
>
>Oops!  Now everyone is gonna think I'm a plumber!
>
>The acronymn "NTP"  (National Tapered Pipe) is the clue and to quote our
>fearless leader, Carroll Smith:  "The threads themselves are so designed
>that the male thread is an interference fit in it's female counterpart".
>It's what keeps ordinary supply plumbing of (some) water and gas lines from
>leaking.
>
>The reason I warned Chris to "respect the taper" is that I've seen a few
>botched jobs which resulted from oversize tap-drills and/or overzealous
>tapping which resulted in threads which could not effect a seal.  There is a
>varience in the taper and in the shank length of the male fittings which can
>also "screw you up" (!)
>
>Carroll continues:  "I flatly refuse to use pipe threads on high pressure
>sustems.  etc., etc."
>
>Tony
>
>

=========================================================
Robert (Bob) A.C. Hamilton, Waverley, Nova Scotia, Canada 
The Man of Many Sunbeams - Alpine, Drophead and Saloon 1953-1954
Home Page: http://www.navnet.net/~hamilton/index.html - REVISED!!!
E-Mail: hamilton@navnet.net 
=========================================================

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