That’s Really Small!
If there were a Guinness Book of World Records category for the narrowest EDM Notch ever made, PH Tool would be in it. Through our proprietary Sinker EDM process, we have developed a unique way to cut our Nano Notches smaller than ever thought possible. Nanos as small as 0.0006” (15 microns) wide have been successfully machined in our lab.
What is the Process?
The trick lies in making a very thin blade, also known as an electrode. We have always been able to machine our electrodes thin, but we’ve pushed the limits of late in order to meet your needs. Electrodes in the 0.0003 – 0.0004” thickness range are required to maintain resulting notch widths under 0.001”. Even at extremely low power settings, an “overcut” results as the microscopic metal particles are evacuated from the notch cavity. In ideal situations, this overcut can be kept in the 0.0003” neighborhood.
How Deep Can We Go?
We get asked this question a lot. The simple answer is about 15 to 1; we can machine a notch approximately 15 times deeper than the notch is wide. This means that our maximum depth at 0.0006” is about 0.009 to 0.010”. If the notch needs to be 0.015” deep, the width will be about 0.001”. Need 0.030” deep? Plan on 0.002” wide then. Certainly, other factors can have an effect on this rule of thumb, but it is a good starting point. Notches required in IDs or in a bore will typically be wider, due to vibration of the smaller electrode rod required for access. Notches with excellent access are the most easily produced Nanos.
What About Length?
Most Nano Notches we’ve made so far have been very short; in the 0.010 to 0.100” range. Longer notches are also possible, however. As with all notches that we machine, Nanos can be shaped to follow a contour, or to have some other tip shape if needed. Thumbnail Nanos with a 2-to-1 length-to-depth ratio are very common, for example.