R-8 Self centering chuck for a mill?

[negatronix]

Right hand cut, Left hand spiral, down cut end mills exist. The helix is backwards from a normal end mill, strange looking things. They put down pressure on the work when cutting. I have only used them in CNC routers when cutting plastic. They do exist for metal cutting, but are not common.

Ahhh... I understand, I think. I will google one and take a look.

Thanks!

 

[negatronix]

Hmmm, just saw your pic in my reply. Thanks again.

 

[Pat of TN]

Yeah, you can't prevent the up-lifting force of a right-hand twist. That's just how it works, unfortunately. I have seen left-hand helix, right-hand-cut end mills as well. Very very curious items.

But, not worth buying for hobby machining and such, if they can be found. Just take things easy.

As a note, running an end mill or reamer or really any cutting tool backwards will basically cause instant destruction. Every carbide end mill, especially, that I have ever seen run backwards simply explodes on touching the piece.

Of course, you could also buy left-hand end mills if your mill will spin in reverse! Just don't get confused.