Im trying to machine a cup die out of 1018 steel, normally we would do this on a lathe but i would like to try to do it on a mill. its pretty much just a pocket thats round at the base, 5in. in dia 6 in. deep. What type of cutting tools should i use? I know mastercam lists a lollipop end mill but i have not yet been able to find one, Would a ball end mill be my only choice?

Do the walls have any draft angle? otherwise you can just use a long series ball nose. I think deflection could be a problem with a full 6" deep pocket, plus you will need to go to a large diameter end mill to get the length you need. The cutter will cost you an arm and a nut.

Are you using the mill to make it difficult on yourself?

Maby a boreing head?

work smarter not harder

What Chuck said...

Use a ball nose endmill..

i found it easiest and best to use the surface rough pocket feature in mastercam... give it a helical entry and go from there...

i's rough it out with a regular indexable endmill and then go in and semi finish it and then finish it with the ball nose...

at 6", you are going to get deflection and chattering.
try using an indexable ball nose cutter