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  • $30 electronic micrometer

    Recently Horror Fright listed an electronic micrometer for $30 (item #98485).

    I never seem to have enough 1" mics -- it's nice to have one at every work station -- so I thought I'd give the HF a try.

    Hey, it seems OK. Unlike some Chinese mics, the "feel" is smooth and consistent. I like it.

    The plastic piece covering the electronics looks a little flimsy, so you wouldn't want to drop the mic on a concrete floor, but then, you wouldn't want to drop your name brand electronic mic on a concrete floor, either. At least if you drop this one, you're only out $30.

    Accuracy is only rated at 0.0001", but that's fine for everyday use.

    Last edited by MTNGUN; 05-05-2009, 11:08 PM.

  • #2
    Originally posted by MTNGUN
    Accuracy is only rated at 0.0001", but that's fine for everyday use.
    You have a mike that measures closer than that?

    Comment


    • #3
      Well, I have an electronic Fowler that displays 0.00001". Whether it is really accurate to 0.00001" is subject to debate.

      By the way, the HF mic displays to 0.00005" (not visible in my photo). The HF website says the mic is accurate to 0.0001", contradicting the label in the mic case that says "accurate to 0.00005".

      To further muddy the waters, the instruction manual says 0.00005" resolution, but 0.00015" indicated error.

      I trust the mic to 0.0001", at best.

      And by the way, when using this mic, be sure to wear ANSI-approved safety goggles, and keep away from children.
      Last edited by MTNGUN; 05-06-2009, 06:32 PM.

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      • #4
        I used the mic for routine measurement chores today and discovered one thing I don't like -- there is no auto on/off.

        Furthermore, the on/off button doubles as the "zero" button. So..... sometimes when you intend to turn the mic off, the mic ends up getting zeroed, instead.

        That was very annoying, so I decided to leave the mic on all the time.

        If the electronics are similar to the chinese calipers, the on/off button only controls the LCD display, not the "brain". If that's the case, battery life will be about the same even if you leave the mic on all the time.

        I'll try it and see how long the battery lasts.

        Otherwise, I am happy with the mic's performance. Accuracy and repeatability seem to be fine.

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        • #5
          .50, what are you shooting?

          Clutch

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          • #6
            Can it switch between metric and imperial easily ?

            I hate auto on / off as everytime you pick the damn thing up it's switched off to save 0.000001 pence worth of battery ?

            My time is worth far more than a battery every 3 months
            .

            Sir John , Earl of Bligeport & Sudspumpwater. MBE [ Motor Bike Engineer ] Nottingham England.



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            • #7
              So they haven't exploded, reversed the polarity of your shop or begun leaking hydrogen sulfide?

              Impressive for a Harbor Freight item!
              This product has been determined by the state of California to cause permanent irreversible death. This statement may or may not be recognized as valid by all states.
              Heirs of an old war/that's what we've become Inheriting troubles I'm mentally numb
              Plastic Operators Dot Com

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              • #8
                Originally posted by MTNGUN
                Well, I have an electronic Fowler that displays 0.00001".
                Holy cow, I guess I'm behind the times. Does the display flicker on the last digit or is it pretty solid?

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                • #9
                  0.00001 or 0.000001 is just like using a 1/10000 indicator - it will drive you nuts!
                  Am I going goofy or what are you guys working to. If I need to be within 1/10000" or 1/1000 mm I would use a Sheffield Gage.

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                  • #10
                    I got one off ebay and its kinda scary how much it looks like a Mitu
                    and like you, Im pretty darn impressed with the thing - think I paid $40+ for mine ....
                    If everything seems to be going well, you have obviously overlooked something........

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                    • #11
                      Originally posted by x39
                      Holy cow, I guess I'm behind the times. Does the display flicker on the last digit or is it pretty solid?
                      The 5th digit on the Fowler is pretty solid if you are measuring something solid. For my purposes -- mostly measuring lead bullets, as shown in the photo -- the 5th digit is meaningless, and I ignore it.

                      Normal micrometer ratchet force is enough to squash lead slightly and alter the measurement. I'm thrilled to get readings consistent to 0.0002" on lead. If you measure the same spot repeatedly, it will keep getting smaller and smaller because each time you measure it, it gets squashed a little more.

                      In fact, instead of using the ratchet, I use the big knob and rely on the torque wrench built into my fingers. The "feel" of the mic is critical (and the Fowler's "feel" is a bit stiffer than I like. The HF mic is better in that respect.)

                      Comment


                      • #12
                        Thats a nice cheap mic but I dont see the point of measuring a bullet. shove it through a die and size it that way. its not like you will chuck it in a lathe and take .0001" off it if its too big.

                        Call me a dummy but whats the point of measuring it ? it seems to me you could get a carbide die made and ram the bullets through it by the thousands and #1 would be the same size as #10,000

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                        • #13
                          MTNGUN manufactures bullet molds, and very good ones at that. They are made individually to the customer's specifications. The bullet cast by the mold must be measured and within tolerance.

                          With that, the best you can expect from any micrometer is a resolution of 0.0001". I would be suspect of an HF mic being capable of producing that level of accuracy. It would be interesting to send one to an independent calibration service.
                          Jim H.

                          Comment


                          • #14
                            Originally posted by JCHannum
                            It would be interesting to send one to an independent calibration service.
                            4-5 years ago my son bought one of the cheap ($20) digital calipers to keep in his tool box that would catch a lot of abuse and was pretty impressed with it. Came time to send all the mics, calipers in for check and on a whim sent the cheapo --- came back as the most accurate of the lot Sent it in for 3 years til it finally got stomped on,- got excellent readings.
                            If everything seems to be going well, you have obviously overlooked something........

                            Comment


                            • #15
                              I agree with Bill on calipers. I tested a harbor freight caliper on about 100 measurements on NIST traceable Starret gage blocks and found no errors not attributable to human error due to mediocre feel.

                              If the mics are like the calipers, they're decent but if they're like the calipers others have taken apart and measured current drain on, they draw as much or more current off as on so to worry about turning them off may be irrelevant. I don't have the reference but I believe it was posted as a response to one of Rick Sparber's caliper threads.

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