Converting a drill press to mill-drill

[Philip Davies]

• I go to a ER25 or 30 series collet systems with the proper Morse taper and either use a draw bar or a lock-pin to retain the taper.

On this conversion I have gone to the ER25 series collets. I bought the HF set of end-mills and only need 3 collets for all that is there 3/8, ½, 5/8 . This gives me 3/16 to 5/8 mills

My son has a full machine shop up to a 30hp Haas CNC mill and if I really need something else I go and use his shop. He is production oriented and I’m more of “enjoy the feel , and the journey type. We give each other a bad time about our different views of the world.

The spindle shaft was small enough that I did not want to bore it for the draw bar. So, on this conversion I’m using a lock-screw retainer. I drill and tap a 10-32 hole in the bottom collar of the spindle shaft. I then seat the MT2 collet and center drill about a 1/8”’ deep hole in the Morse taper. I then use a 60^o chamfer on the hole.

When I put the MT into the spindle I line up the MT chamfer with the screw and push it in loosely, I then tighten down screw and it centers the taper on the chamfer, I then tap the taper home and finish tightening the setscrew, because the setscrew and the chamfer share the same center on a fully seated MT, by seating the MT and tightening the set screw the MT is locked in the fully seated position. I retighten the screw after the first pass just for safety sake.

The screw is a mild steel screw that has been sharpened and end-blunted. If I forget to unscrew it before I drive out the MT when changing tools it just shears of the screw and doesn’t mess with the chamfer on the hardened MT. The first one of these I did I used a hard set screw and tore up the MT when I forgot to loosen it once. Lesson learned

In my thinking it isn’t if you forget is when you forget, as you get older you will forget things. As I get older I spend more of my time contemplating the here-after--------what am I here after!!!!!

Thank you for a very interesting thread. I have bought an “engineering” bench drill and compound table hoping to start milling, but unhappily the chuck and the collet holder are equally liable to pull out and I consider really I was sold a pig in a poke by the supplier. Unfortunately, I don’t have the expertise to replace the bearing or install a lock screw.