[JWB_Machining]

Ok, so today I have to take an approximately 11" long piece of 4340 (Tested as Rockwell C 30) with a 2" diameter and perform a few operations. I'm hoping someone can help me with the speeds n feeds I plan on using. I have to take this piece of stock and make 6 pieces that have 1 13/16" 16 TPI for a 1/2 on the outside, a through hole of a half inch and then mill out that through hole for a length of about 1/2" so that I can have 1" 14 TPI on the inside. I hope this makes sense. So here's what I plan on doing....

I'm going to face off both end of the part and turn it down to 1 13/16. I plan on using a carbide insert tool, I will have 400 SFM and 10 IPR with a depth of cut of .025". Are these settings good or should I be more or less aggressive? Also is a better idea after facing to use a centerdrill on one end and use my tail stock so that I can machine down the largest length possible and keep my diameter consistent or should I just have 6" hanging freely turn that down then flip the part n turn the rest down?

Then I plan on cutting this bar into lengths and drilling 1/2" holes through all of them.

Then on my Mill I'm going to mill out a center hole to about .930" I'm going to use a .375" TiAlN coated endmill. Is it wise to just use IPS' circular pocket for this? I plan on using SFM of 100 and 11 IPT? Once again too slow or too aggressive?

Then I'm going to thread mill the inside and outside threads. Last time I tried to thread this material I did it at 400 SFM with a Feed of 2.0 IPM. I did this in one pass which made a depth of cut of about .035". When I used my short thread mill this worked pretty well. However I tried out my Solid Carbide Thread mill that was about 3" long and I had terrible chattering with these settings and wore out my thread mill insert? Was the problem just that the thread mill was so long it wasn't as rigid as my short thread mill so it chattered a lot and I should have cut back on my depth of cut? The machinery's handbook suggests I used SFM of 60-95 and IPR of 83-20

So to recap...
Turning: SFM = 400 IPR = 10
Milling: SFM = 100 IPT = 11
Thread Milling: SFM = 400 IPM = 2.0

These good or bad or any suggestions?

[JWB_Machining]

Oh Also I Forgot to ask this. When i'm Milling out my center hole, I want to go a total depth of 0.6", how large can my depth of cut be? rmeeber I'm using a 2 Flute TiAlN Coated Solid Carbide End Mill.