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  • Evan
    replied
    I can read text files on the inside of my eyelids, or so I tell Gert, she reckons I'm nodding but we all know different
    It's commonly accepted that you cannot read anything when dreaming, that reading isn't a feature of dreaming. It is for me. I sometimes dream of things that require reading. Once it was a lotto number but I could only make out 3 of the numbers. On a lark I bought a ticket with those numbers and won ten bucks.

    Eidetic memory isn't like what people usually think, which is that the Eidetiker has the "photographic" ability to remember anything and everything. It does mean that when a specific scene is recalled the recall is very complete. I can visualize scenes that I recall that way and they include inconsequential details such as the clouds in the sky or in the case of the large caliper the shape and color of the wooden case it was in including the internal wooden supports that held the instrument in place while packed and the fact that the instrument was displayed in the case standing up.

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  • Evan
    replied
    If the need for temperature compensated measuring instruments were a MUST, they would be readily available. I have yet to turn up one in any form.
    The common mechanical wrist watch in the better quality versions were temperature compensated.

    You aren't showing much imagination Jim. As the list is much too long to post here try this search:

    http://www.google.ca/search?hl=en&sa...G=Search&meta=

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  • John Stevenson
    replied
    Originally posted by Evan
    I can review the images in my head.
    I can read text files on the inside of my eyelids, or so I tell Gert, she reckons I'm nodding but we all know different

    .

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  • IOWOLF
    Guest replied
    YAWN, I just cant believe we have nothing better to do than this.

    But Hey, we all waste time in different ways,Me I make chips.

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  • JCHannum
    replied
    If the need for temperature compensated measuring instruments were a MUST, they would be readily available. I have yet to turn up one in any form.

    I do see a few CMMs that claim temperature compensation, but further reading reveals most are apparently temperature adjusting ala the Albion gage. They compare temperatures at various points, and use a computer program to bias the output. This is not true compensation as being discussed here.

    Of all the catalogs I have, and instrumentation I have had or seen, I have never seen any common measuring instrument, or for that matter, lab or other high precision instrument that has temperature compensation. Many are marked with a temperature, 68*F on older, non ISO gages, to indicate the temperature at which they are calibrated. This information is all that is necessary for the user to make any adjustments needed.

    And, no one needs to be concerned what the part size is at non standard temperature. The end use has nothing to do with the dimensioning for machining. Those dimensions are given at standard temperature.

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  • Evan
    replied
    I just got off the phone with Evans bear dog, and he confirmed that he saw it also.
    First of all, she is a she. And, she knows a lot more than 50 words. Furthermore, she isn't allowed to answer the phone.

    Evan, is that a typo or another red-herring?
    edetic/eidetic
    No, it's an acid. I make a lot of typos and didn't notice it as I was on the way out to do some work. Note the note on the lower right of this post.

    Evan your contention that the instrument is compensated for itself and not for the difference between the instrument and the part makes no sense at all.
    You must be joking. That is the entire rational of temperature compensating a measuring instrument. The point is for it to perform in the same fashion regardless of temperature, usually limited to some range of temperature.

    No one cares what the part size is at nonstandard temperature.
    Oh really? I do. My double arm tracking drive wouldn't work if I hadn't taken changes with temperature into account. Also, one does not always have the luxury of being able to measure something at STP. In order to make an accurate measurement you MUST have an instrument that produces a reading that is either temperature compensated for changes in the instrument cause by changes in temperature or those changes must be well characterized so a compensation can be applied to the data if necessary.

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  • tdmidget
    replied
    Evan your contention that the instrument is compensated for itself and not for the difference between the instrument and the part makes no sense at all. The whole point of accurate measurement is to allow parts to fit regardless of who made them or where. For instance parts for the Boeing 787 are made all over the world, dispersed as far as Italy and Japan. If not all measured to the same standard temperature, how will they fit in Seattle? No one cares what the part size is at nonstandard temperature. Why would anyone want such an instrument? If one was curious about the size change then take your hot or cold part to inspection and check with an instrument that IS at standard temp. Of course then that instrument will be out of service until it returns to the standard temp.

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  • Swarf&Sparks
    replied
    Evan, is that a typo or another red-herring?
    edetic/eidetic

    I hope it is the former, or your argument is moot.

    Leave a comment:


  • Willy
    replied
    Originally posted by mochinist
    I just got off the phone with Evans bear dog, and he confirmed that he saw it also. For only knowing 50 words or so, we communicated surprisingly easy.
    Give yourself some credit...you know a whole lot more than 50 words...I've read some of your posts and they had a whole lot more than 50 words in them, mind you some words were used more than once.

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  • mochinist
    replied
    I just got off the phone with Evans bear dog, and he confirmed that he saw it also. For only knowing 50 words or so, we communicated surprisingly easy.

    Leave a comment:


  • Evan
    replied
    All I can add is that the memory isn't at all dim. I still have some degree of the edetic ("photographic") memory I had when young. I can review the images in my head.

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  • JCHannum
    replied
    Dim memory of an unreliable source aside, I think it is quite safe to assume that Starrett never manufactured a temperature compensated vernier caliper.

    Even if one were to exist as described, it is not a temperature compensated caliper, but one which the operator, for some reason, could fudge manually to bias the reading, which would only be correct at only one single dimension, and a guess at that at best.

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  • Evan
    replied
    I asked you to furnish proof. Show us a vernier caliper from any manufacturer with temperature compensation.
    Sorry, but I cannot. The item in question is no longer on sale on e-bay. I am not however a habitual liar. As I said, it may have been a special. All the instrument manufacturers will make specials if a customer so wishes. As I recall the mechanism was very simple. The scale on the jaw was movable via a thumb screw. It was adjusted to match the temperature on a scale below the vernier markings. This isn't much of a change as the vernier scales are adjustable for calibration anyway.

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  • ckelloug
    replied
    ligito,

    My answer was tongue in cheek too. Did you not note the plagarism from Macbeth's monologue? I just couldn't set it up without answering the question. Not all humor is good humor and I'll file this one under humor that I made that was not found exceptionally funny by the audience.



    --Cameron

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  • ligito
    replied
    [QUOTE=ckelloug]ligito,

    We only test prime grade steel measuring instruments on this thread. You kids with your plastic calipers: get off my lawn

    That was tongue in cheek. I bought it for measuring rod.
    I have an analog diak caliper but very little experience in how to use it and forget how to read it without retraining, everytime.

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