How to cut internal and external radius

So I am getting ready to finish up a part tomorrow and I need to cut one internal radius 1/8, a external 1/4 radius, and then a 1/4 rounded shoulder.

I am wondering how others cut these. To you ease into it and rough it out? Take it in one go? Do it prior to hitting finished diameters? I have a carbide insert/tool holder for the external 1/4 radius. I plan on grinding a tool for the rounded shoulder. The internal is whats going to be tricky. It is 7" deep inside the bore(bore is fairly large) The radius's are positive (i guess wouldn't be a problem if they went negative). I have been google searching about how people do their's . Even my machinist text book I learned out of for vo-tech is very vague.

The material is Nickel 200 which is a issue all in of itself. Any helpful hints tips or thoughts would be greatly appreciated.

On an internal radius using a manual machine (you don't say which, manual or CNC), you are pretty much limited to form tools. Might could do it with a tracer and single point, but that would be about the only option. Not sure how nickel is going to react to a form tool, though. Fortunately, that's a pretty small radius.

Trig it out and step it off. Gets rid of chatter because you are never taking a full width cut. Here is a five step 5/16 internal radius being done with a .214 radius tool. Finer the steps the better it looks.

http://img.photobucket.com/albums/v337/johnoder/20 Heavy Greaves Klusman/Headstock/DCP_1386.jpg

Thanks for the thoughts. I figured I'd have to make a form tool and rough it out and blend it all in. Just hate how deep in the hole it is. New at this shop so still learning what all tooling they have hiding around.

Mike. Nickel wants to pile up on every type of cut. It has been a fight to go from a solid piece out to 5.5" bore. The coolant they run doesn't do any good from what I can tell; though I run it to keep part from getting too hot. Found tap magic helps the rat's nest from wanting to stick to the insert. It'll be interesting to say the least. Thanks again Mike and John.

Ball nose end mills make excellent form tools for inside radii. Sometimes you need to
run the machine in reverse of course.

For outside radii the cheat is: a corner rounding end mill. Use it like a form tool. Bonus
is you get four cutters of the same size.

I have never cut nickel,but have cut SS and 4140 in a similar situation.I had good luck with rex95 and cutting oil.The trick was the right RPM and feeding into it.If it were in front of me tomorrow I would grind a good sharp tool rex or carbide,then at that diameter I would prolly start at about 60-100 RPM.

When I start my cut I would jam that sucker right in there then out before it has a chance to chatter,if you keep the tool loaded and yank it out at the very moment it has completed a full revolution at cut depth you stand a good chance of a slick finish,if you try to sneak up on it and let it rub just a little bit you will get a crappy chattered finish.

I'm talking hand feed it and plunge right in and snatch it out before it has a chance to start rubbing.

it helps to jog your machine spindle while cutting to keep it from chattering.