Quote Originally Posted by komatias View Post
The collets clamp on a 3/4" diameter cylinder but it also allows the toolholder to have contact with the spindle nose. This makes tool length offset through the tool table possible as you can premeasure the length of each tool and it is repeatable. I find them worth every bloody penny when you have to change tools for a specific job as it saves having to touch off each one. In conjunction with the power drawbar you literally fly through.

The holders look like this one:

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Tormach in the US claim to have invented this but there are a number of sources out there that manufature them.

Needleworks probably has a set or ER20 chucks but you can get ER16 up to ER32.
You just hit the nail on the head my friend, that`s exactly what I am using. Only difference is that I am in fact using ER 32 chucks, which do not have the TTS toolholder rings on them, therefore to use an atc, I would have to shrink fit the rings onto them, but that will be a future project.