Why is 1/2" EMT 3/4" in diameter?


Old 12-23-07, 01:32 PM
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Why is 1/2" EMT 3/4" in diameter?

1/2" EMT seems to be about 3/4" in diameter. What does the 1/2" refer to?
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Old 12-23-07, 01:46 PM
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"Trade-Size"---- ( not 1/2" as measured by scale, rule )
Old 12-23-07, 02:49 PM
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Inside diameter not outside diameter.
Old 12-23-07, 02:55 PM
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well, even that isn;t right. EMT is listed as .622 in. inside dia.

the closest to actual 1/2 in ID is schedule 80 pvc with .526" i.d.

As PATTBAA said, it is merely "trade size" 1/2" conduit or in the newer more politically correct metric designator dimension, 16mm.
Old 12-25-07, 12:55 AM
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Back when I worked for a Big Box store we had a customer buy some 2X4s Came back a little later irate as all get out because they were only 1-5/8" thick and 3-5/8" wide. Was convinced everybody in the store was lying about the size in order to cheat him.
Old 12-25-07, 07:42 PM
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"Why is 1/2" EMT 3/4" in diameter? "

My stock answer is "just to piss you off!".. Looks like it worked!
Old 12-26-07, 08:59 AM
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When people ask here a question like, "How many #12 wires can I fit in 1/2" conduit?", we have to ask two questions: what kind of conduit and what kind of wire? That's because each of the dozen or more different kinds of 1/2" conduit has a different actual inside diameter.

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