Not sure which to use Bore or Drill

[jscott6SWZG]

I have a hole to make.  Thanks to a.laas i can reliable drill holes.

The hole 6.5 mm dia has a notch cut down the length of it.

I am concerned that the drill might catch on the edge of the slot and tool breakage will ensure.  (like what happens when i drill it by hand.

I have been using a bore operation with a long reach 3/16 ball end mill. Lots of screeching and a very poor  finish.

So which tool should I use 6.5 mm drill or 3/16 ball end mill?

See set up: rhs, operation bore5

[a.laasW8M6T · Accepted solution]

Yea you can't drill that hole if the slot is already there.

Best idea would be to drill the hole before milling the slot.

If you cannot do that, then using the bore toolpath is the best option, but NOT with a ball nose tool you ideally want a short flute reduced shank tool like this

https://www.harveytool.com/products/variable-helix-end-mills-for-aluminum-alloys---square---long-rea... 

Ballnose tools should really only be used for 3d surfacing or radius milling applications

I'm not sure why you are conventional milling that hole either, you would get better results climb milling

[jscott6SWZG]

Gotcha.  Just the info I needed.    Getting ready to buy the correct tools pretty quick

thank you