Harold,

I've always preferred fly cutters with 3/4" shanks. It makes it much easier
to go from an the cutter to a drill chuck or other device.

In my case (ER 32), any round vs. R8 shank will make life easier. Is
there something specific to your setup that is specific to 3/4"?


If the shanks
are less than 3/4", I'd likely feel differently. I couldn't get
interested in a 1/2" shank, for example. With the smaller shanks, you're
asking for chatter.

3/4 it is. I have an ER collet in that size, and the Enco set with that
shank size has 1.5, 2, and 2.5 inch diameter cutters, which is a nice
range for most of what I do.

That choice leads to 5/16 inch tool bits. Would HSS square bits be a
good place to start?


Unless you're machining steel, taking heavy cuts, rigidity isn't much of an
issue. I'd suggest you permit your work to make the decision. If you
expect you'll be doing lots of big stuff with deep cuts and large diameter
circles, the R8 would be a better choice.

I am unlikely to need to take deep cuts. With the exception of my
bandsaw helping me to improve my rough cuts, I try to avoid being in a
hurry.

Thanks!

Bill