One of the new features in the upcoming version of TouchDRO app is tachometer readout. The beta version of the application had full tachometer support for some time now. Over the last few weeks I added directional tachometer support to all four controllers. In this post I will try to give you some ideas on how to build a tachometer for your mill or lathe using commonly available parts. Your setup will vary, of course, but the main principle will be the same, so you shouldn't have too much trouble to adapt these designs to your particular needs.
Read more »DIY Tachometer for Your Mill or Lathe
TouchDRO Version 2 Now Available
It's been a year since I released the last version of TouchDRO, and it's definitely time for some updates. If you've been following this blog, you might recall that I made "Beta" version available at the end of last year, and was planning to push a new version out around February of this year. Well, it's the end of October, but finally I got it stable enough that I feel pretty good about letting it into the wild. There is a ton of changes, including many new features that people have requested. I will try to cover the important ones in this post, and over the next couple of weeks (as the time allows) will dig deeper into some of them.
Read more »ER-40 Collet Chuck for JET 1024 Lathe
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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.
Read more »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.
Read more »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.
Read more »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.
Read more »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.
Read more »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.
Read more »TouchDRO 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.
Read more »TouchDRO Quadrature Adapter Details
TouchDRO Quadrature board is designed to interface standard quadrature scales to 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).
Read more »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.
Read more »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.
Read more »TouchDRO 2.5 Release Notes
I'm really excited to finally say that after many months of "Beta" testing, version 2.5 of TouchDRO has been released to "Production". Even though it didn't earn a full digit reales number of 3.0, this version encompasses a lot of major changes under the hood. Many of the changes were made in response to your feedback and requests, while others lay groundwork for future functionality, so let's take a look at the most noteworthy changes in the new version.
Read more »Choosing the Right TouchDRO Adapter for Your Scales
I started offering pre-made controllers/DIY kit earlier this year, and have received a number of emails asking to clarify which DRO controller to chose and why. At the time of this writing I offer three versions of the controller hardware: two as a pre-assembler board and one as a DIY kit. Each controller is designed to interface with specific set of scales and uses firmware that is specifically optimized for that particular hardware. The purpose of this post is to explain what each controller was designed for and what are the benefits/tradeoffs of using it as opposed to the other controllers.
Read more »Connecting iGaging Scales to TouchDRO Controller
If you read some of the earlier posts on this blog you will quickly see that the times were much simpler four years ago when it comes to iGaging scales: there was only one kind and red wire was "Vcc", black wire was "Ground", and so on. Since then iGaging has gone through several revisions of the original DIgiMag scales and has introduced AbsoluteDRO and EZ View scales. My goal for this post is to explain what are the different iGaging (and generic scales made by Shahe) that TouchDRO supports and how to connect them to the BlueTooth DRO controller.
Read more »SIEG X2 Mini Mill CNC Build - Introduction
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SIEG X2 Mini Mill CNC Build - Component Selection
In the last post I outlined my plan for building a CNC mini mill from a set of SIEG X2 castings. As the first step I wanted to order the parts for the mill itself, ignoring the steppers, controllers, etc. and make sure that I can get it up to snuff. There is no set budget for this project, so the choice of the parts is mostly based on availability (and common sense). The two areas I wanted to concentrate on are spindle accuracy and overall repeatability. With that in mind, in this post I will explain what parts I chose to buy and why.
Read more »Sneak Peek of the New TouchDRO Version
It's been awhile since the last major TouchDRO version release and I'm getting an increasing number of emails asking if I'm still developing the app. The answer is "definitely yes", and the new version is getting very close to be ready for beta testing. It has a number of new features and countless quality-of-life changes. I've been testing it in my shop for some time now and most of the functionality is pretty stable so it's a good time to post a quick preview of some of those changes and new features.
Read more »Virtual Layout Feature Preview
In the last post I showed some of the updates coming to the next version of TouchDRO. The new version will include a lot of tweaks, UI changes and improvements aimed to make the DRO even more flexible and efficient to use. As is, TouchDRO can already do much more than and old-school DRO, but next version is getting a number features that will push the limits of what you can do with a non-CNC mill or lathe. One of those features is the ability to set a background image in layout view and use the mill or the lathe to trace the contour.
Read more »Blu-DRO Now Uses the TouchDRO iGaging DRO Adapter
I get a fair number of emails asking if I sell fully assemble board, in a box, ready to go. Although I have seriously thought about offering a fully turn-key version of the iGaging DRO controller, I couldn't get the numbers to pensil out: the cost of making a custom injection molded enclosure is ridiculously high, and 3D printed enclosures take too much time and I couldn't find a way to make it scale. Meanwhile, I knew that Al at blu-DRO.com has been selling fully enclosed Arduino TouchDRO controllers. I've met Al "virtually" on TouchDRO Bata Testing Google+ community, where he had been a frequent poster, always willing to help or answer questions. Furthermore, the feedback I got from people who purchased blu-DRO units was very positive about his level of customer support, etc. After some "noodling around" I decided to email Al and see if we can find a way to work together. A few emails later we decided that I will sell the boards to Al in bulk at a bit of a discount so he can use them in his units. This seemed to be a win-win situation: Al would get more robust controllers for the blu-DRO and I can stop worrying about creating a turn-key version of TouchDRO.
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