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  • #76
    Hmmmm… if I'm trying to read stuff fairly easily and rapidly I would want .001 to be expanded to more than by 20 times. .02 is still only about the thickness of two business cards. And that ain't too easy for most of us to see.

    I think I'd want more of a 40:1 taper so .001 is .04 difference. And even kinder to old eyes and ease of spotting small differences would be 50:1. But that isn't a deal breaker. Nothing says that we need to be limited to just one tapered slot. A set of "fingers" with a few slots could work just fine. The worse would be that you are at the transition and have to switch to the adjacent slot to get a reading. If we're looking at a 50:1 expansion and a range from 1/32 up to 1/2" and all the number, metric and letter drills in between that's a total of .032 to .500 or .468. And .468 x 50 =23.4 inches of slot. Split that into three slots and our total gauge is only a bit over 8 inches long when we allow for lead in and over run on the other end. Or if we split it into 4 slots then just a little over 6" for the same reason.

    Another possible problem is that I've noticed that some drill bits are tapered down slightly from the cutting end or along the flutes to the shank. I just double checked on four good name brand drills (two Dormer and two Walther) and the shanks are .002 smaller than the proper size seen when measured across the flutes at the cutting nose. So that could lead to some confusion on sizing if you're using the round shank as your measuring point. Never mind any galling or wear from the chuck over that same area. And that would be why I prefer to measure drills for size at the cutting ends. And that would be tough to do with a thin and tapered slot. Oh sure, we could just push a known drill size in and mark where it comes to rest. But some brands do not seem to share this slight taper and they would read as larger and easily become confused with near number or letter sizes.
    Chilliwack BC, Canada

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    • #77
      A little off topic here but only realized a couple years ago that what I've been calling 1" NF is actually NS 14 tpi,Bolt supplier said the 1" NF 12 tpi are uncommon these days.

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      • #78
        What you say in your last paragraph is one important point that I tried to make earlier in this thread. Perhaps you said it better and some will pay attention.

        When you add a possible 0.0005" to 0.001" variance from the marked size at the cutting end to another 0.002" at the shank end, you rapidly lose any faith in any tapered slot device, no matter what the taper angle is. At least, I certainly do. This is why I suggested a device based on a digital caliper.

        Some will talk about a caliper having a +/-0.001" or even a +/-0.002" accuracy, even the expensive ones. I have a number of digital, dial, and even Vernier calipers and regularly use them or at least a few of them. I have checked my favorite, 8" digital against my shop blocks and have always found it to be spot on in it's readings. It reads in 0.0005" increments and it does not deviate even that much when I check it. And it IS A CHINESE IMPORT. I do use a technique that is designed to eliminate the primary sources in errors when using calipers which, IMHO, is the cocking of the movable jaw assembly which renders the two jaw edges non-parallel. My technique consists in NOT using the thumb wheel or knurled surface to push the movable jaw closed. Instead, I use my other hand to squeeze the two jaws near the center line of their contact with the object being measured. That insures that the two jaws are as parallel as possible while taking the measurement. Of course, I also keep the gib screws in the movable head adjusted as tight as possible while allowing smooth movement.

        This technique does work nicely on the working (fluted) end of drill bits if you can get a bit more than a half turn of the spiral inside of and in contact with the caliper's jaws. This will certainly give you a much more accurate measure than any tapered slot and also more accurate than even a micrometer used on the shank.

        Once you have that caliper reading, you can use it as you like. A simple lookup table or a cable to some kind of device that will read it and display the result.



        Originally posted by BCRider View Post
        Hmmmm… if I'm trying to read stuff fairly easily and rapidly I would want .001 to be expanded to more than by 20 times. .02 is still only about the thickness of two business cards. And that ain't too easy for most of us to see.

        I think I'd want more of a 40:1 taper so .001 is .04 difference. And even kinder to old eyes and ease of spotting small differences would be 50:1. But that isn't a deal breaker. Nothing says that we need to be limited to just one tapered slot. A set of "fingers" with a few slots could work just fine. The worse would be that you are at the transition and have to switch to the adjacent slot to get a reading. If we're looking at a 50:1 expansion and a range from 1/32 up to 1/2" and all the number, metric and letter drills in between that's a total of .032 to .500 or .468. And .468 x 50 =23.4 inches of slot. Split that into three slots and our total gauge is only a bit over 8 inches long when we allow for lead in and over run on the other end. Or if we split it into 4 slots then just a little over 6" for the same reason.

        Another possible problem is that I've noticed that some drill bits are tapered down slightly from the cutting end or along the flutes to the shank. I just double checked on four good name brand drills (two Dormer and two Walther) and the shanks are .002 smaller than the proper size seen when measured across the flutes at the cutting nose. So that could lead to some confusion on sizing if you're using the round shank as your measuring point. Never mind any galling or wear from the chuck over that same area. And that would be why I prefer to measure drills for size at the cutting ends. And that would be tough to do with a thin and tapered slot. Oh sure, we could just push a known drill size in and mark where it comes to rest. But some brands do not seem to share this slight taper and they would read as larger and easily become confused with near number or letter sizes.
        Paul A.
        SE Texas

        And if you look REAL close at an analog signal,
        You will find that it has discrete steps.

        Comment


        • #79
          In the interest of actually being practical, I think this is the answer: https://www.generaltools.com/hobby-d...onal-size-bits
          25 miles north of Buffalo NY, USA

          Comment


          • #80
            That's nice to know. I have been using Dropbox for around two years now and have not had to pay a single penny. I do not back up my entire drive there, I only upload things that I want others to get. My first use for it was in transmitting articles to VP.

            Google is definitely a possibility, but I have resisted their services because they are an ADVERTISING company, first and foremost. And they use every "free" service that they provide to us to gather data about us to target advertising themselves and to sell to other advertising companies so that they can also target such advertising. And Google retains everything from the very first Google search that anyone ever made. They have all and I do mean all e-mails that ever went to or from a G-mail account. Even if both the sender and the receiver and everyone who may have received a CC have all deleted them a long time ago. Your files on their server? I hope you do not have anything in there that you don't want to be shared with everyone at Google.

            Free services? Heck, they should be paying us to use them. And we should know each and every such use and they should pay us OUR rates for that usage. I would not be surprised to find out that Dropbox does the same. And that is why I carefully control what I upload there.

            Oh, OK I will stop the rant.



            Originally posted by Bob Engelhardt View Post

            Google Drive - pretty much any kind & size file (& free, unlike Dropbox)
            Paul A.
            SE Texas

            And if you look REAL close at an analog signal,
            You will find that it has discrete steps.

            Comment

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