MadModder

Gallery, Projects and General => How do I?? => Topic started by: John Rudd on September 13, 2020, 01:20:48 PM

Title: End mills
Post by: John Rudd on September 13, 2020, 01:20:48 PM
I finally managed to get round to trying to sharpen some end mills I have....

Having ground the clearances ( primary and secondary ) I need to grind the central clearance.........


How do you guys do yours?


I've seen the centre relieved by grinding across the face forming a X......Some of my cutters have the centre already relieved...like a counterbore....I have nothing that will grind the centre... :scratch:
Title: Re: End mills
Post by: chipenter on September 14, 2020, 01:28:25 AM
I use worn angle grinder 1mm cutting disks for gashing , that pretty much opens the centre but they won't plunge cut any more , or for Clarkson type a tungsten carbide drill in the lathe at 150 rpm will do it .
Title: Re: End mills
Post by: John Rudd on September 14, 2020, 03:10:17 AM
Jeff,
Thanks for the tips.....esp the tc drill bit.....surprised that will do it...but are we talking solid carbide or something akin to masonry drills?

Plunge cutting not an issue....
Title: Re: End mills
Post by: chipenter on September 14, 2020, 03:36:36 AM
Solid every time I have very short spotting drill 60 degree , have tried reground masonry but they tend to wobble and not enough clearance , tip don't leave the swarf on the ways it's very fine and sharp .