# how do they hollow out the needle in hyperdermic needles?

**URL:** https://boards.straightdope.com/t/how-do-they-hollow-out-the-needle-in-hyperdermic-needles/68280
**Category:** Factual Questions
**Created:** [June 10, 2001, 7:55am UTC](https://boards.straightdope.com/t/how-do-they-hollow-out-the-needle-in-hyperdermic-needles/68280 "2001-06-10T07:55:15Z")
**Posts on this page:** 17
**Page:** 1

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### Author: ![Universal\_Dialect](https://avatars.discourse-cdn.com/v4/letter/u/dfb087/32.png) [@Universal\_Dialect](https://boards.straightdope.com/u/Universal_Dialect)
#### Post date: [June 10, 2001, 7:55am UTC](https://boards.straightdope.com/t/how-do-they-hollow-out-the-needle-in-hyperdermic-needles/68280/1 "2001-06-10T07:55:15Z")

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So how do they hollow out the needle in hyperdermic needles?

And since they are massed produced, how do they ensure every needle has a perfect hollowness and isnt mistakingly clogged up .

Regards,  
UD

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### Author: ![don\_t\_ask](https://avatars.discourse-cdn.com/v4/letter/d/e68b1a/32.png) [@don\_t\_ask](https://boards.straightdope.com/u/don_t_ask)
#### Post date: [June 10, 2001, 8:01am UTC](https://boards.straightdope.com/t/how-do-they-hollow-out-the-needle-in-hyperdermic-needles/68280/2 "2001-06-10T08:01:23Z")

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I don’t think they hollow them out… I think they’re made hollow.

But, hell, I could be wrong.

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### Author: ![Universal\_Dialect](https://avatars.discourse-cdn.com/v4/letter/u/dfb087/32.png) [@Universal\_Dialect](https://boards.straightdope.com/u/Universal_Dialect)
#### Post date: [June 10, 2001, 8:03am UTC](https://boards.straightdope.com/t/how-do-they-hollow-out-the-needle-in-hyperdermic-needles/68280/3 "2001-06-10T08:03:46Z")

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You mean like your brain?!

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### Author: ![Enola\_Straight](https://avatars.discourse-cdn.com/v4/letter/e/dec6dc/32.png) [@Enola\_Straight](https://boards.straightdope.com/u/Enola_Straight)
#### Post date: [June 10, 2001, 8:07am UTC](https://boards.straightdope.com/t/how-do-they-hollow-out-the-needle-in-hyperdermic-needles/68280/4 "2001-06-10T08:07:42Z")

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I’m fairly certain the manufacturing process is as follows:  
the needle stock starts out as a length of foilwhich is folded over around a super-hard tungsten wire and extruded into a tube one millimeter thick. A machine then merely cuts the tube square off at one end and angled at the other, then mates the finished needle to the syringe.

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### Author: ![K3v1n](https://avatars.discourse-cdn.com/v4/letter/k/b19c9b/32.png) [@K3v1n](https://boards.straightdope.com/u/K3v1n)
#### Post date: [June 10, 2001, 8:23am UTC](https://boards.straightdope.com/t/how-do-they-hollow-out-the-needle-in-hyperdermic-needles/68280/5 "2001-06-10T08:23:52Z")

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I missed this episode of Mr. Rodgers Neighborhood where they showed how these were made… 😉 I saw the wagon one though.

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### Author: ![DougC](https://avatars.discourse-cdn.com/v4/letter/d/7feea3/32.png) [@DougC](https://boards.straightdope.com/u/DougC)
#### Post date: [June 10, 2001, 12:19pm UTC](https://boards.straightdope.com/t/how-do-they-hollow-out-the-needle-in-hyperdermic-needles/68280/6 "2001-06-10T12:19:38Z")

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- 
  - 
    - There may be more than one way it’s done, but the way I know of is as follows: it starts with a relatively thick rod, say maybe an inch diamater and twelve inches long. Then they drill the center out of it so it is a tube (say a 1/2 inch hole). Then they place it in the first of a series of machines which stretches it lengthwise by the ends and applies heat to the middle of it at the same time. It gets thinner and longer each time, and they cut off the “thick” ends and keep drawing the “inner” section in other ever-smaller machines over and over again until it’s the size they want. The needle will not “clog up” or collapse at all using this method, and surface irregularities in the original piece of material get drawn out in the process: the inside and outside surfaces end up mirror-smooth with no polishing needed at all.

- It is possible to make needles thin enough to inject a single cell with this way, although usually for that they use a single-pass machine which creates a tapering needle made of glass, not a straight one made of metal. In this they place a small piece of glass laboratory tube, and around the center of it is a heating coil, which , -heats up red hot. As the glass stretches, it gets thinner and thinner until it breaks, but the end will be very tiny and it will still be a tube all the way through. \*\*\*\*\*They showed one of these machines working during a station commercial on the Discovery Channel for a long time, but they offer no explanation for what it is: as you see it, it seems to be some machine doing nothing even though you can see the red heating coil around the glass tube, and then the machine snaps, pulling the ends of the tube a couple inches apart. Each end is then usable as a needle. I dunno if they still run the commercial. - MC

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### Author: ![Una\_Persson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/una_persson/32/346_2.png) [@Una\_Persson](https://boards.straightdope.com/u/Una_Persson)
#### Post date: [June 10, 2001, 1:21pm UTC](https://boards.straightdope.com/t/how-do-they-hollow-out-the-needle-in-hyperdermic-needles/68280/7 "2001-06-10T13:21:01Z")

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> [@](#):
>
> \*Originally posted by enolancooper \*  
> \*\*I’m fairly certain the manufacturing process is as follows:  
> the needle stock starts out as a length of foilwhich is folded over around a super-hard tungsten wire and extruded into a tube one millimeter thick. A machine then merely cuts the tube square off at one end and angled at the other, then mates the finished needle to the syringe. \*\*

They cut it off at 1 mm thick? Have you ever seen a syringe needle? Try 28-30 gauge, not 1 mm.

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### Author: ![mblackwell](https://avatars.discourse-cdn.com/v4/letter/m/5fc32e/32.png) [@mblackwell](https://boards.straightdope.com/u/mblackwell)
#### Post date: [June 10, 2001, 3:25pm UTC](https://boards.straightdope.com/t/how-do-they-hollow-out-the-needle-in-hyperdermic-needles/68280/8 "2001-06-10T15:25:09Z")

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> [@](#):
>
> \*Originally posted by Universal Dialect \*  
> \*\*You mean like your brain?! \*\*

You really shouldn’t insult people like that in GQ, especially when they are trying to help answer your question.

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### Author: ![Bosda\_Di\_Chi\_of\_Tricor](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bosda_di_chi_of_tricor/32/16845_2.png) [@Bosda\_Di\_Chi\_of\_Tricor](https://boards.straightdope.com/u/Bosda_Di_Chi_of_Tricor)
#### Post date: [June 10, 2001, 5:01pm UTC](https://boards.straightdope.com/t/how-do-they-hollow-out-the-needle-in-hyperdermic-needles/68280/9 "2001-06-10T17:01:30Z")

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They are hollowed out by little, tiny, gnome junkies.

Used to work for Santa, before they flunked the urine test.  
:wally

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### Author: ![astro](https://avatars.discourse-cdn.com/v4/letter/a/9dc877/32.png) [@astro](https://boards.straightdope.com/u/astro)
#### Post date: [June 10, 2001, 5:05pm UTC](https://boards.straightdope.com/t/how-do-they-hollow-out-the-needle-in-hyperdermic-needles/68280/10 "2001-06-10T17:05:27Z")

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> [@](#):
>
> \*Originally posted by Universal Dialect \*  
> \*\*You mean like your brain?! \*\*

Quite the witty smackdown there UD! What are you… 13 years old?

Who the hell are you to act snotty after asking a GQ. The answer you got might not have been complete but it was correct with respect to the nature of the manufacturing process. Typical SS hypo needles are extruded steel tubes not drilled out blanks.

Learn some manners or go home.

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### Author: ![Lynn\_Bodoni](https://avatars.discourse-cdn.com/v4/letter/l/e47c2d/32.png) [@Lynn\_Bodoni](https://boards.straightdope.com/u/Lynn_Bodoni)
#### Post date: [June 10, 2001, 5:55pm UTC](https://boards.straightdope.com/t/how-do-they-hollow-out-the-needle-in-hyperdermic-needles/68280/11 "2001-06-10T17:55:32Z")

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> [@](#):
>
> \*Originally posted by mblackwell \*  
> \*\*
> 
> > [@](#):
> >
> > \*Originally posted by Universal Dialect \*  
> > \*\*You mean like your brain?! \*\*
> 
> You really shouldn’t insult people like that in GQ, especially when they are trying to help answer your question. \*\*

In fact, don’t insult people AT ALL in any forum outside of the BBQ Pit.

This is an Official Warning.

Lynn

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### Author: ![Speaker\_for\_the\_Dead](https://avatars.discourse-cdn.com/v4/letter/s/c77e96/32.png) [@Speaker\_for\_the\_Dead](https://boards.straightdope.com/u/Speaker_for_the_Dead)
#### Post date: [June 10, 2001, 6:28pm UTC](https://boards.straightdope.com/t/how-do-they-hollow-out-the-needle-in-hyperdermic-needles/68280/12 "2001-06-10T18:28:35Z")

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I’m glad I’m not the only one that saw UD’s response as a little rude. Anywho… Wouldn’t the extruding process on such a minute (size of needle) massproduction scale take a whole lot of human supervision?

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### Author: ![Universal\_Dialect](https://avatars.discourse-cdn.com/v4/letter/u/dfb087/32.png) [@Universal\_Dialect](https://boards.straightdope.com/u/Universal_Dialect)
#### Post date: [June 10, 2001, 8:41pm UTC](https://boards.straightdope.com/t/how-do-they-hollow-out-the-needle-in-hyperdermic-needles/68280/13 "2001-06-10T20:41:51Z")

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What was insulting, was that I asked a question, and my question was critised without an answer being given.

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### Author: ![Speaker\_for\_the\_Dead](https://avatars.discourse-cdn.com/v4/letter/s/c77e96/32.png) [@Speaker\_for\_the\_Dead](https://boards.straightdope.com/u/Speaker_for_the_Dead)
#### Post date: [June 10, 2001, 8:48pm UTC](https://boards.straightdope.com/t/how-do-they-hollow-out-the-needle-in-hyperdermic-needles/68280/14 "2001-06-10T20:48:25Z")

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Actually, he was just giving you an answer to the best of his knowledge. That information happened to conflict with yours. Critisizing your question would have been like “Haha, HOLLOW OUT? You have to be kidding! They make them hollow!”. Also, another thing to remember is to attack the person’s statement, and not the poster him/herself.

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### Author: ![Homer](https://avatars.discourse-cdn.com/v4/letter/h/df788c/32.png) [@Homer](https://boards.straightdope.com/u/Homer)
#### Post date: [June 10, 2001, 11:01pm UTC](https://boards.straightdope.com/t/how-do-they-hollow-out-the-needle-in-hyperdermic-needles/68280/15 "2001-06-10T23:01:03Z")

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> [@](#):
>
> \*Originally posted by Universal Dialect \*  
> \*\*What was insulting, was that I asked a question, and my question was critised without an answer being given.
> 
> \*\*

You need a thicker skin to survive in the hurly-burly world we call the SDMB. I will reserve my comments on your behavior until someone starts the inevitable pit thread about you, because if you continue acting like this, it won’t be far off.

Please don’t presume that anyone here is REQUIRED to answer your question. You should be grateful when it is done so.

–Tim

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### Author: ![Mahaloth](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mahaloth/32/1079_2.png) [@Mahaloth](https://boards.straightdope.com/u/Mahaloth)
#### Post date: [June 10, 2001, 11:23pm UTC](https://boards.straightdope.com/t/how-do-they-hollow-out-the-needle-in-hyperdermic-needles/68280/16 "2001-06-10T23:23:07Z")

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> [@](#):
>
> \*Originally posted by Universal Dialect \*  
> \*\*What was insulting, was that I asked a question, and my question was critised without an answer being given.
> 
> \*\*

Uh, that’s criticized. Don’t worry, they’ll teach you to spell lot’s of neat words in the 8th grade.

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### Author: ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)
#### Post date: [June 11, 2001, 12:08am UTC](https://boards.straightdope.com/t/how-do-they-hollow-out-the-needle-in-hyperdermic-needles/68280/17 "2001-06-11T00:08:32Z")

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If you don’t like the answers you’re getting, **Universal Dialect** , then there’s clearly no reason for this thread to stay open. You might want to consider whether there’s any reason for you to be here at all, if you respond to everyone who tries to help you that way.
