Before I go much further, let me introduce you to some of my ongoing projects.
Over the last several months I've been collection various bits and pieces for a CNC router. I've already built a Dremmel based “hardware store” model a few years ago, but it turned out to be largely worthless for what I wanted to use it, so this time I decided to go all in and build the machine to be as rigid as possible, capable of cutting sheet aluminum among other things. The machine will be a “moving gantry” style and will have overall footprint of 27”x27” with 4-6” of vertical travel. Since I have a working mini mill and a lathe, I decided to go with heavy duty aluminum for the construction.
DRO for the mini mill
About a year ago I got a Harbor Freight mini mill (Sieg X2). I went with HF, since it uses R8 spindle, so when time comes to get something more rigid I will be able to keep my tooling. It didn't take much time to realize that I REALLY wanted to have a DRO. Initially I was planning to buy a Shumatech DRO-550, but then I figured that making one would be much more fun, so I ended up ordering three IGagings scales from Grizzly for at total cost of $105. These are not calipers, but rather a two-piece scales, so for some time I used them without the DRO box, since I've been busy at school, but the project finally got underway this winter. Again, true to my principle of “if it's worth doing, it's worth overdoing”, I went slightly overboard, and decided to add BlueTooth, so I can send simpel G-code directly to the DRO. At this point I have a working “proof of concept” for the hardware, but I will go into details in one of the future posts.
CNC router controller
The common approach to a DIY CNC machine control is to have an old PC running EMC or Mach3, but where is the fun in that? Instead of doing what the common sense tells me to do, I decided to make an embedded controller for the router that can receive the G-Code over the network or BlueTooth. While the interpreter won't be as full-featured as EMS, interpreting G-Code isn't all that complicated, and microcontroller-based system should cope with the task very well. A few weeks ago I received a development board from ST Microelectronics (STM32F4Discovery) and the little beasty comes with ARM Cortex MCU, floating point unit and a DSP. In my estimation it should have no problem running the mill at all.
Various mill and lathe mods
I've had the mini mill and a 9x20 Harbor Freight lathe for a bit under a year. Those of you who own HF tools probably know that what HF sells isn't exactly top of the line equipment. While both tools have been indispensable, they have a lot of “room for improvement”. Lathe would definitely benefit from the tail stock being coaxial with the spindle and having right angle between the X and Y movements on the mini mill won't hurt either. In addition to the standard “finishing”, I want to add some mods and gadgets. In the near future I'm planning to convert the mill to a belt drive, add the DRO box (the scales are starting to drive me nuts... they turn off after 1 minute or so), replace the gibs with either brass or Delrin AF (or Torcite), convert the lathe to DC drive, add motorized power feed to the mill and the lathe. Again, as things develop, I will post pictures and details
There is more small stuff I'm tinkering with, but chances are you will see much more about each of the projects I've mentioned.