Inconel part finishing strategy?

[BRIAN.T]

Inconel 718 isn't something I work with too often so I need some opinions.

Let's all just pretend this photo is the real part, it isn't, but it gets the idea across. There is a lot more going on with the real part.

This part will be done in a 5 axis, it it for the most part comprised of prismatic shapes, they are however all blended with a .187 radius.

I can finish about 40 percent of it just profiling with a bull mill, the upper diameter of the 4 "feet" and maybe 1/2 of the OD, however then I need to surface the remainder. This will lead to a bunch of mediocre blend issues. And inconsistent surface finish.

Alternatively I could surface the ENTIRE part, which would remedy the blend issues. And with a .187 fillet, I'm likely going with a 1/4 ball mill, but this will probably take about 14 hours.

What would you guys do?

 

[Euclid]

Use a trochoidal milling as much as possible with Bull mills with biggest possible corner radius. Then semi-finish and finish

 

[nissan300ztt]

I primarily turn Inconel 718 and I have special Roughing inserts for Inconel that are tougher and harder than the Inconel. I leave .005" on all surfaces and I get mirror finish every time.

 

[Mr.Chipeater]

It sounds like his question is about finishing strategy and nothing to do with 718.

If its a time vs appearance debate, the answer is always "it depends". what are the finish requirements? is the customer ok with slight mismatch or steps? can you post process aka bead blast to blend tooling marks?

You're going to have to decide where you fall in the time vs appearance chart based on the job value and requirements to pick which strategy fits best.