# NF Machine screws availability?

**URL:** <https://boards.straightdope.com/t/nf-machine-screws-availability/202994>\
**Category:** Factual Questions\
**Created:** [September 21, 2003, 4:40pm UTC](https://boards.straightdope.com/t/nf-machine-screws-availability/202994 "2003-09-21T16:40:16Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Dewey\_Finn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dewey_finn/32/4222_2.png) [@Dewey\_Finn](https://boards.straightdope.com/u/Dewey_Finn)\
**Post date:** [September 21, 2003, 4:40pm UTC](https://boards.straightdope.com/t/nf-machine-screws-availability/202994/1 "2003-09-21T16:40:16Z")

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There is a piece of equipment in my office that’s missing a screw. I measured it (using a thread gauge) and determined it to be 6-40 x 9/16". I’ve looked in several hardware stores and haven’t found this size in any of them. Actually, they only seem to carry NC machine screws and not NF machine screws. Does anyone know why? I’d also appreciate the name of a mail order or internet store where I can buy it.

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**Author:** ![Doc\_Nickel](https://avatars.discourse-cdn.com/v4/letter/d/5fc32e/32.png) [@Doc\_Nickel](https://boards.straightdope.com/u/Doc_Nickel)\
**Post date:** [September 21, 2003, 5:08pm UTC](https://boards.straightdope.com/t/nf-machine-screws-availability/202994/2 "2003-09-21T17:08:50Z")

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I have pneumatics fittings in 6-40, as well as taps for the same, but no screws.

Try McMaster-Carr or MSC (should be easy to find with Google.)

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**Author:** ![Dewey\_Finn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dewey_finn/32/4222_2.png) [@Dewey\_Finn](https://boards.straightdope.com/u/Dewey_Finn)\
**Post date:** [September 21, 2003, 6:42pm UTC](https://boards.straightdope.com/t/nf-machine-screws-availability/202994/3 "2003-09-21T18:42:56Z")

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McMaster-Carr’s website is down so I can’t check it. But neither MSC nor Grainger carry that thread size. I can’t understand why it’s not available.

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**Author:** ![Rocketeer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rocketeer/32/4437_2.png) [@Rocketeer](https://boards.straightdope.com/u/Rocketeer)\
**Post date:** [September 22, 2003, 5:41pm UTC](https://boards.straightdope.com/t/nf-machine-screws-availability/202994/4 "2003-09-22T17:41:27Z")

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Geez, are you sure it isn’t metric? It seems screwy (oops) to use an odd-sized screw, when a cheaper standard one would do. And if your copier is made overseas, metric would make sense.