CyberTech Digital Photo Laser Tachometer

I have been having a very good experience with this tachometer. It seems very accurate, of course with any HAND held tachometer you have to make sure you keep your hand VERY steady, especially at higher speeds.. if your hand moves even a tiny bit it will throw the readings way off. I use this to get a precise RPM reading on my milling machine so I can synchronize a tapping head to the spindle. Since the machine uses a variable speed belt, it is impossible to get the machine to produce a precision spindle RPM, but thanks to this tachometer, I don't need precision RPM, I just need to know what it is, then feed that number into my CNC controller to do the math and come up with a feed rate that matches whatever the spindle RPM is. I find that if I rest my hand on my vice when I take the reading, it's very accurate.. If I try to just stand there and hold it at the spindle, well it's all over the place... it's not the fault of the device, it's a simple fact that if my hand moves slightly between rotations, the time it took to get the reflection will be different. I suspect that those experiencing accuracy issues do not realize how critical it is to hold steady, in my opinion at higher RPMs, it would be impossible to hold ANY device steady enough to get a consistent reading.. but if you stabilize yourself on something that is attached to whatever you are measuring, then you can get accurate readings. I have been tapping holes using this tachometer as my spindle speed reference for about a year now with this device and synchronization is perfect.