Monthly Archives: December 2016

Old-School Selling of the Exploration of Mars

My youngest son has been fascinated with Elon Musk's plans for colonizing Mars. He is not that different from his old man because in my youth Wernher von Braun (Figure 1) had me captivated with his plans for human-crewed missions to Mars. As I described von Braun's plans for exploring Mars to my son, I realized the both Musk and von Braun applied similar state-of-the-art marketing approaches. Continue reading

Posted in Astronomy, History of Science and Technology, Management | 2 Comments

Tapered Side Angle Measurement

I thought I was done with my metrology review when I encountered an excellent set of discussions at the Hobby-Machinist web site. They advertise themselves as "The Friendly Machinist Forum" and all signs indicate that is true. In addition to excellent tutorial discussion, there are some excellent metrology discussions on that site, and I want to document a few of the examples that are shown there. Continue reading

Posted in Metrology | 2 Comments

Christmas Lights in Minnesota

While I do not, many people in Minnesota spend much time and money on decorating their homes in lights for Christmas. Some people think it has all gotten out of hand. Here is a home in my neighborhood where one neighbor just gave up because of the incredible effort on the home next to him. Continue reading

Posted in Humor | Comments Off on Christmas Lights in Minnesota

Quick Backup Current Limit Calculation

I was in a meeting this morning when I was told a battery pack had insufficient capacity to meet a 24 hour backup time requirement. While in the meeting, I grabbed a specification for the battery the test engineer was using, did a quick calculation of the backup time results that the test engineer should have expected, and what needed to change in order to pass the backup time requirement. While I have discussed different kinds of battery calculations in numerous blog posts, I thought this one was more typical than most and reflects the kind of work done daily by battery engineers. Continue reading

Posted in Batteries | Comments Off on Quick Backup Current Limit Calculation

Using Excel's Solver and VBA For Repetitive Table Calculation

I will be providing some employee training on Excel in January, and I need an example of how to automate the use of Excel's Solver add-in – a powerful optimization tool that few engineers use effectively. When I give a training seminar, I make a serious effort to show how I use Excel on real problems. While I generally use Mathcad for most optimization applications, Mathcad does not support integer programming – an optimization method where some or all variables are restricted to be integers. Here is where Solver shines – it supports integer programming. Continue reading

Posted in Construction, Excel | 9 Comments

Another Angle Measurement Using Roller Gages Plus Error Analysis Example

While I covered angle measurement in a previous post, that approach can be difficult to apply for acute angles. The approach presented in this post works well for acute angles, but will not work for obtuse angles.

As part of this post, I will also demonstrate how to perform a tolerance analysis on this approach. The tolerance analysis is important in understanding the level of accuracy required in your linear measurements to achieve the desired angle accuracy. Continue reading

Posted in Metrology | 1 Comment

Demise of the Pearl Harbor Strike Force

I just watched a wonderful BookTV presentation by three authors on the WW2 attack on Pearl Harbor, which occurred 75 years ago today. While I am generally familiar with what happened during that attack, I had not looked at the details of the attack. In particular, this show motivated me to look at the Imperial Japanese Navy (IJN) attack force composition and what happened to these ships over the course of the war. The fate of these ships reflects what happened to the rest of the IJN during the Pacific War. Continue reading

Posted in History Through Spreadsheets, Military History | 4 Comments

Measuring Round-Over Radius Using a Roller Gage

This blog post shows how to measure the radius on a rounded corner (a.k.a. bullnose) using a roller gage. I saw this method being used on this web page, and I wanted to document it here for future reference. Continue reading

Posted in Metrology | 1 Comment

Maximum Reach Estimates for Low-Voltage DC Power Delivery

It is no secret that I prefer Mathcad for the vast bulk of my computational work, but I live in a world in which Excel is universally available. As such, I must prepare Excel workbooks for others to use. Today, I was asked to prepare an Excel worksheet that our salesman could use for estimating the maximum range over which different combinations of wire and voltage could deliver useful power. I include my Excel workbook here for those who wish to follow along. Continue reading

Posted in Electronics | 1 Comment

Bore Diameter Measurement Using Gage Balls

I am continuing to work through the metrology examples on this web page as part of junior machinist self-training. Today's technique shows how to use gage balls to measure the bore diameter of a cylinder (Figure 1). You can measure a bore diameter using a micrometer, but I have concerns that I might be measuring along a chord instead of a diameter – this error would result in too small of a result. The gage ball approach should eliminate that type of error. Continue reading

Posted in Metrology | 5 Comments