Originally Posted by
lens42
I got a used, but in very nice shape, 2018 Haas CM-1 (small office mill) with some Techniks ISO-20 ER16 holders. These holders are about $200/ea, so I figured I'd try out a $70 eBay Chinese holder to see how it compared. The eBay special was not bad (about 0.00025" TIR measured on the inside of the ER16 taper). Then I measured some of my fancy Techniks holders and was shocked to see them read between 0.0005" and 0.001"! They all read about the same, measured on the inside of the ER16 taper, so I don't think they have been abused. Runout on these is supposed to be under a tenth, which makes me think I'm doing something wrong. Rotating them 90 degrees in the spindle changes the TIR between 0.0005" and 0.001, but when I check an empty spindle, it reads pretty much perfect (less than a tenth). I can't believe that all my holders can be this bad, but the eBay Chinese special reads pretty good, so I'm stumped. I also cleaned all the tapers with no change in results. Are Technik's specs BS?
I added some videos of the measurements if anyone is interested.