[acerocket]

I am going to be taking delivery of a Femco Durga CNC lathe shortly. This will be my first CNC lathe and I have a question concerning drilling holes. I have a job ready for when the machine arrives and it has a .25" diameter hole drilled 1" deep in the center of the part. I am thinking of using an ER25 collet holder with shanked body to insert into one of the ID tool holders and then I have the option of using drill bits up to 5/8" for various jobs. Is this an acceptable way to go about drilling a hole while maintaining flexibity in hole size? If not, could anybody offer some alternatives?

Thanks

[Geof]

We do it all the time with ER16, ER25 and ER32 holders.

There are two things to watch for:

Sometimes the ID tool holders are not perfectly one center; this does not matter as much with a boring bare but with a drill it is more important so you should check alignment.

Sometimes with a drill you can slowly push it back into the collet; we rig up a stop behind large drills so this does not happen.

One thing we have found handy is with these collet holders you can use corner radius endmills as small boring bars for shallow holes. Only one corner is used for boring and sometimes it possible to use the opposite corner for OD turning and save a tool change. You do have to reverse the spindle direction.

[fmari]

My lathe customers use these all the time. I have a large variety in 3/4 and 1 inch shank. Er16,20,25,32, and 40.