Member Since: October 17, 2012

Country: United States

  • Marking with the sharp edges seems to work better with:

    • high quality calipers that are actually made from hard metal.
    • machinists marking blue. (The last machine shop that I worked with used a marking blue spray paint.)

    The scratch that one can make with the caliper points is very faint, so it shows up better with the contrast of marking blue.

    An alternate to the marking blue (according to some quick and dirty googling that I did to make sure I wasn’t talking out of my sits-upon) seems to be sharpie marker. Use the marker to color a patch where the marking will be made, and then scratch through the sharpie ink to show a high-contrast bright line. Cleans off easily with alcohol, cooling fluid (this might be a problem), and I’m sure a good handful of common shop solvents. (But not water.)

  • What about an improvised hammer? ;-) (grinning, ducking, and running)

  • As I said, I also usually forget about it. But the times that I do remember to use it I find my measurement is less fiddly to take.

  • Yay! Thanx for getting to this, Shawn. You did forget the one measurement that I also usually forget about, the step measurement. It tends to be easier to accurately achieve as long as there is clearance because instead of relying on the lesser stiffness of the depth gauge to get plumb and the narrow end of the beam to get square, it actually uses the stiffness of the beam to get plumb and the width of the jaws to get square. (See the last measurement on this page.)

    I am glad to see that you did cover how to read a vernier scale. It is a more advanced scale reading technique, but there are a lot of tools (particularly older) that use that measurement scale. Just having an understanding of it might help when confronted with some old piece of equipment picked up for pennies at an estate sale. And even if one doesn’t remember how to read it, one would hopefully recognize it as a vernier scale and then know the proper keyword search to find the answer. (Sometimes it is more valuable to know how to find an answer than to just know the answer itself…)

    (Edited word order and spelling error for clarity.)

  • Yeah, deadlines seem to get in the way of properly finishing often.

  • I presume the 500 max you used for the dial/knob elements was arbitrary. But visual representations like that are displaying a ratio, and if the metric the ratio is applied against is arbitrary the actual ratio itself is then arbitrary. It looks nifty, but really doesn’t inform.

    This begs the question, what would a more informative max be? Twice daily recommended so TDC of the dial would be the daily recommended value? Personal goal? Something else?

    Just out of curiosity (I’m not familiar with these elements), what would the dial/knob look like when over ranged?

  • It isn’t the law, but it certainly crystallizes the spirit of how many people who built this nation came to originally enter it’s borders.

  • So, if you turned it off because you want it off, all it takes is a minor power glitch/brownout to turn it back on again? IMHO that is a problem. Not your design (the Echo that is), but more of an extended reason for an external power circuit.

    An easy way for the photon circuit to “remember” the last state is instead of controlling a transistor to pass power to the Echo, have the photon control a latching relay.

  • I haven’t gotten into the connected home bit yet, so I don’t know some of the actual use details. All this circuit does is disconnect and reconnect the power from the puck. Does the puck automatically turn-on (boot up) when power is applied? Or would you need to manually turn it back on?

    Thinking through further: Do these pucks remember if they were on when power was removed and then restore that state when power is restored? (I.e. if there is a power outage then when power is restored does it try to turn on if it was on beforehand, and stay off it it was off beforehand?) Same question for your power control module.

  • This looks similar to the scanner used by Neato Robotics vacuums. If the performance of my XV-21 is any indication, in many situations the proper application of SLAM should give good results. (Avoid thin or highly reflective obstacles.)