Edge finder tool holder for use with weldon flat end mills

[jaco...@gmail.com]

I received my PNC a few days ago and noticed the tool holder that come with the edge finder is 3/8" diameter. I have a handful of end mills with 3/8" shank diameter and see that they fit perfectly inside the edge finder tool holder. Is there any reason why I shouldn't use the edge tool holder for an end mill?

[Jonathan]

You could use the edge finding tool holder to mount a 3/8 shank tool, however there are a couple of potential issues to be aware of. The set screws are both located on the same side. This means that tightening them enough to hold a tool will tend to push the tool off center. You should make sure that the amount of runout on the tool shank is acceptable before you use it. 

Second, the set screws are not going to hold the tool as tightly as a collet does. This means that there could be issues with the tool pulling out of the tool holder. I have not tested this setup so I am not sure what the limits are. I would start with machining softer materials such as wax or soft wood then work your way up. You should be able to see if the tool stick-out is changing using the tool probe. 

Jonathan