Toolholder Comparison

​One more time. Figure 1 are the stability lobe diagrams for the same endmill in the same machining center, sticking out exactly the same amount from five different toolholders. Which one is the shrinkfit? The hydraulic? The power shrink? The milling chuck? The side lock? I am not telling (and not stupid enough to do so). In Figure 2 we changed to the same type endmill, but longer, and you can see the results are vastly different. Winners and losers are different. Take-aways: you cannot predict the best toolholder without measuring the system's dynamics and shorter is not always better.