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Need Part Indentified

  1. Oct 15, 2009 #1
    I would appreciate it if anyone can identify this part for me. It's about 20 inches in length, and about 5 inches in diameter. I have no idea what it is.

    http://img129.imageshack.us/img129/2717/photoau.jpg [Broken]
    http://img200.imageshack.us/img200/1623/photobol.jpg [Broken]
    http://img129.imageshack.us/img129/1826/photoc.jpg [Broken]
    http://img119.imageshack.us/img119/5397/photod.jpg [Broken]
    http://img131.imageshack.us/img131/213/photoe.jpg [Broken]
    http://img26.imageshack.us/img26/8459/photofh.jpg [Broken]
    http://img119.imageshack.us/img119/5117/photogp.jpg [Broken]
    http://img119.imageshack.us/img119/2706/photoh.jpg [Broken]
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Oct 15, 2009 #2


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    I've never seen anything like that; it looks like the offspring of a fluorescent bulb and a typewriter platen.
    Is the shell glass or plastic? Are those spirals threads cut into the end piece, or a coil wrapped around it? Does it appear to be air-tight?
    I don't know if the answers are relevant, but it can't hurt to get as much info as possible.
  4. Oct 15, 2009 #3


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    Maybe its a fancy comtemporary french press?
  5. Oct 17, 2009 #4
    At first glance, it looks like a conveyor roller, but I have no idea why you would want to see inside a conveyor roller. The outer shell is likely either acrylic (plexiglas) or polycarbonate, likely the latter.

    I'll describe what I see and maybe that will help myself or others figure out what it is.

    The central rod provides the center of the structure and the short protrusion on one end would could plug into a journal bearing, the other end has a thru-hole that could use a pin to retain a plate between the pin and the endplate of this thing.

    The two threaded rods are perhaps used to pull the end pieces together but I cannot see exactly how that would work - is there a hex or slot in one end of them?

    I'm thinking the end fittings are perhaps some sort of off-the shelf hub system because the large threads one one of them are not used and you don't machine threads into a custom hub if you don't need them. The other end fitting has thread holes thru which are somewhat typical of a hub system where you would use those threads and loose bolts to disassemble the hub from a press-fitted shaft. They ran the smaller diameter threaded rods thru those holes instead.

    It looks like the end plates were fabricated and welded on in order to provide a smaller hole for the central rod because the hubs had IDs that were too large.

    OK there's the description - it seems clear that this was designed for rotation but not at high speed or high torque. I don't see how it would be driven except perhaps the two holes for the threaded rods were also used to match a pair of drive lugs.

    Some sort of tumbler perhaps? But the inside would be severely scratched up if ever used to tumble anything at all hard.

    Maybe a reaction chamber of some sort where the experimenter or machine operator needed to watch the progress of the reaction? How easy is it to take apart and re-assemble?

    Fun question.
  6. Oct 17, 2009 #5


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    Nice diagnosis, Spacester. You haven't convinced me of the thing's identity, but I like the way that you think.
    As you mentioned yourself, though, there are still inconsistencies that argue against the conveyor solution.
    Something that might help is for Reltyu to disclose where and under what circumstances he obtained the object. If, for instance, it was found in the weeds behind a place of business, the odds are that it's related to that business and no longer functional. Conversely, if he sniped it off of a military transport truck... :uhh:
  7. Oct 17, 2009 #6
    maybe it is from a photocopier, and is designed to retain non-migrating point charges on its surface so as to pick up ink dust for mechanical transfer to paper?
  8. Oct 17, 2009 #7


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    Another sensible analysis, Arithmetix.
    It still, however, leaves questions. While the length might be suitable for a large photocopier, the diameter seems excessive. Also, any photocopier/printer rollers that I've seen were metal, with no 'innards'. Those internal bits such as the side rods and the threads make no sense to me as referenced to any mechanism that I'm familiar with. They must have some purpose, or they wouldn't be there. (Unless, of course, someone just cobbled it up in order to have a prank.)
  9. Oct 18, 2009 #8
    Thank you for your replies! Here's some more info:

    the clear cylindrical casing seems to be a very hard plastic/plexiglass-not glass.

    The black coiling is not a spring b/c it doesn't expand or collapse,
    it seems to only be there to provide lateral "give" if/ when the metal screwhead inside the hole hits it. There is a mechanism inside that metal part that the coil is wrapped around. notice the hole mostly covered by that coiling? well inside is a carved metal "bushing" which has a tracking carved into it which allows this two-pronged "thing" w/ a caphead that looks like a heavy duty metal thumbtack with 2 needles/dull "prongs". anyway these two prongs follow the tracking/threading on the bushing. And it's important to know that the threading/tracking is designed to be reflexive like a figure-8, in that it is carved so that the thing that follows its track one way is guided back and forth/up and down rather than just one way like a screw and then another way when needing to be unscrewed). So no the coil is not a spring it just wraps around that metal part and seems it's only purpose is to keep the screw and bushing mechanism inside and also to provide the "give" when it gets hit, just like a rubberband would but less so i guess.
    Last edited: Oct 18, 2009
  10. Oct 20, 2009 #9


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    Okay, so it's a drum cam inside there. In order for it to have any use, the carrier ('prongs') would have to be attached to some other moveable part. Is there evidence of something like that?
  11. Nov 7, 2009 #10
    I apologize for not responding till now. I will find out the answer to your question Danger and get back to you. In the meantime would anyone else like to jump in and make a guess?
  12. Apr 21, 2011 #11
    Maybe Pheo knows what this is . . .

    If Pheo doesn't know, does anybody else have any ideas?

    I still have this thing.
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