How to Build the Mixed Scale Digital Readout Kit

Last Monday I shipped the first batch of orders for the Mixed Scale DIY DRO Kit, so those of you that have placed an order have likely already received it. I know that many of the people who ordered the kits have electronics experience and won't need a step-by-step assembly instructions. With that said, I designed the kit to be very beginner-friendly, so in this post I will go over the assembly process in some detail, so someone with limited electronics experience should be able to follow it and end up with a working DRO controller.

Do-it-yourself DRO Mixed Scale Controller Kit

Mixed Scale Controller DIY DRO Kit is designed to simplify the build process of the "Mixed Scale" DRO controller. As the name suggests, this version of the controller comes as a do-it-yourself kit that consists of a bare printed circuit board, MSP430 microcontroller pre-programmed with the "Mixed Scale" firmware, BlueTooth transceiver, and all of the necessary parts to build the voltage shifter circuit. The board is primarily designed to run the Mixed Scale firmware and interface with 1.5V and/or 3.3V scales and calipers, but can be easily tweaked to work with quadrature encoders instead.

TouchDRO Adapter for Glass and Magnetic DRO Scales

TouchDRO adapter for Glass and Magnetic DRO Scales is used to interface glass and magnetic scales that use standard quadrature encoders to the TouchDRO Android application. It supports up to four scale inputs, directional tachometer, and touch probe input. All inputs are buffered and 5V-tolerant. Scale inputs can be either single-ended, or differential (for better noise immunity).

TouchDRO BlueTooth Adapter Board for iGaging Scales

Those of you that follow the TouchDRO Users G+ community know that I've been working on a pre-made adapter board for iGaging scales. Today I finished testing the first batch of the boards and will ship them out to the people that ordered them. The intention of this post is to clarify what the board does and doesn't do, as well as provide some basic instructions how to set it up.

Tablet for TouchDRO for $49.99

I test TouchDRO on a number of devices ranging from 10" Galaxy Note Tab to an old LG phone with 4" screen. One of the reasons being that there are subtle differences between devices, event if the OS version and build are the same and some devices work much better than others. For years I've been recommending Google Nexus 7 or Galaxy Tab 7. I use both devices for development and in the garage and stand behind my recommendation. Unfortunately those tablets aren't cheap. Up until now the alternative was to get a no-name Chinese tablet. While these tablets cost half as much, quality of software and hardware varies wildly. For some time I've been looking for an inexpensive tablet that is readily available and offer consistent and reliable performance and finally I found one that fits the bill: Amazon Fire 7" tablet for $49.99.

New Beta Version of TouchDRO Now Available

For almost a year since the last major release of TouchDRO (v2.0) I've been working on the new features and enhancements that will be released in v2.5. Some of the changes are pretty deep under the hood and will not be immediately obvious, but there is a number of features that will make the application more flexible and more convenient to use. This includes a complete revamp of the low-level readout processing with better metric mode support, new functions, improved graphical mode and several quality-of-life enhancements.

Connecting iGaging Absolute Scales to TouchDRO

Recently I posted a mini review of the iGaging Absolute DRO Plus scales that covered the some basic information on the connection scheme, etc. As I mentioned in the last post, the scales use a different communication protocol. Unlike the DigiMag scales, these scales require additional circuit between them and the MSP430 LaunchPad board. As promised, in this post I will provide instructions on how to connect the scales to the MSP430 Launchpad controller.

Working with iGaging Absolute DRO+ Scales

Since their initial release iGaging Absolute DRO Plus scales seem to be gaining momentum. They have a lot going for them, but unfortunately they are incompatible with the original 21-bit iGaging protocol. For some time I've been getting an increasing number of request to add support to the controller firmware, so a few months ago I went ahead and purchased a 6" scale to experiment with. Finally last weekend I added support for these scales to the "Mixed Scales" MSP430 controller firmware. In the first part of this post I will explain what's different about the Absolute DRO+ scales and provide a quick overview of the data protocol; in the second part I'll provide detailed instructions on how to connect them to the MSP430 Launchpad DRO controller.

Making Lathe Tachometer - Part 1

A few posts ago I offered some general ideas on adding a tachometer to TouchDRO setup that covered some theory and a basic example circuit. Since then I've received a ton of emails asking for more details, so in the next few posts I will provide a detailed start-to-finish example of building a tachometer for my Jet 1024 Lathe. In the post "DIY Tachometer for Your Mill or Lathe" I covered the basic of tachometer operation and provided a basic tachometer circuit using a IR emitter/receiver couple. A number of people wanted to use a Hall effect sensor with a magnetic encoder disk, so I will go that route for this design. Along the way I will use this project as mini-tutorial for some of the basic TouchDRO functionality.

ER-40 Collet Chuck for JET 1024 Lathe

ER-40 Collet Chuck mounted on the lathe

Every time I get to use my JET 1024 Lathe I have a hard time wiping the grin off my face. The machine is very sturdy and accurate for its size, and has served me very well so far, but has a few minor annoyances. For example, the spindle has a straight 1.25" bore with no Morse taper. Recently I had to make a few dozen studs for a steam engine project using a 4-jaw chuck where using collets would've been much more efficient and convenient. Since using collets in the spindle is out of question, the only option left is to use a collet chuck, so last month I set out to either make or buy one. After going back and forth between C5 and ER-40 I ended up choosing ER-40 for various reasons.