TTS in machining usually refers to Tormach Tooling System. I believe they have a trademark on TTS with that meaning.


Basically it consists of a 3/4 inch R8 collet that has been face ground so that when clamped on a 3/4 shank tool the face of the collet is slightly above (retracted into) the face of the spindle. The "proper" TTS tools and tool holders are simple a 3/4 shank tool/holder with a collar that registers against the spindle nose. Often this system is paired with a spring loaded drawbar that is released by compressing the springs.


I have a Tormach mill with TTS system with power drawbar as described above. It works "okay," but if you get some chatter or excessive loads with larger tools they can pull out of the spindle. I've seen it happen. The limitation is the strength of the spring stack, and the pressure rating of the pneumatic cylinder. I've added springs, tightened the draw bar, and increased the air to release it. It works marginally well. I don't have issues unless I forget and do something stupid.


All of that is just back ground facts. Yes other systems are better. Whether you think its good or bad I do not care. My question is would going to a 1" collet have more or less hold on a suitably sized tool/holder given that no other factors would have changed?


I can grind the face on a good quality collet, and I can make my own tools and tool holders. I have made a few of my own tool holders for special application, and that I can do so relatively easily is one of the big positives about TTS for me.