tool options for profiling 4" deep

Ukraine Train said:

I'm working on a part made from 4140A where one side needs to be profiled. It's about 4.25" tall x 8" long and I have 200 to do. I found some 1" end mills with 5" flute length but they're $1200+, and I don't think one will do the whole job. I was thinking of getting an inserted end mill like this, and then I'd at least be able to use it in the future:
View attachment 147465

What kind of finish do these leave? Would I still need to come back with an end mill to get a 250Ra finish? Any other suggestions?

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Bobw said:

https://www.maritool.com/Cutting-Tools-End-Mills-Reduced-Shank-End-Mills-Reduced-Shank-4-Flute/c78_79_219_220/index.html

You can hang these guys out about a mile, or choke up on them as much as possible...
They are pretty darn rigid since the shank is SOLID and only about .015 smaller than the
endmill diameter. A 3/4 should do you fine... Take a few passes, but you should be able to
haul ass... Use shorter cheaper tools to do the shallow stuff, and save the long expensive stuff
for when you need it.

On the 5" of flute, I've found that when you start playing with long endmills, with long flute lengths,
things just get ugly.

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