- Joined
- May 10, 2012
- Messages
- 995
I use both end mill holders and collet holders in TTS. The collet holders, or R8 collets tend to have a bit less runout. This isn't that critical on larger end mills, where the runout is much less than the feed per tooth. When you get to smaller end mills, it does make a difference, because if the runout is as large or larger than your feed per tooth, then one side of your mill is doing all the work (and twice as much as you intended it to). I use the holders pretty much interchangeably down to 1/4", from there down I use the collet holders exclusively. As for pullout, I have had the TTS toolholder pull out of the TTS R8 collet, but I've never had and end mill pull out of an ER collet. There is a very good white paper on Tormach's website that details what needs to be done to get the maximum holding force from an R8 collet. It includes test data, and is an interesting read for using any collet system. As for the ER collets, they have to be tight. The recommended torque values on them are surprisingly high.
Here is the link to that paper:
http://www.tormach.com/document_direct_download.html?doc_id=163
Here is the link to that paper:
http://www.tormach.com/document_direct_download.html?doc_id=163