[Gun-Machine]

I am looking for End Mills for a specific milling application and I will need them to be able to cut with a depth of at least 1 inch to finish the inside of a piece I am working on.

a 1/8" End mill that can cut 4140HT with a cutting depth of at least 1" is needed.

Any help would be appreciated. Thanks.

[HuFlungDung]

I see one available at Harveytool.com but I'm glad I'm not the one who has to use it in 4140

[plasmator]

Maritool has one:

http://www.maritool.com/Cutting-Tool...duct_info.html

I highly recommend Maritool - awesome stuff.

[skullworks]

You are asking for real problems and a special (and very expensive!) tool that will self destruct with any abuse.

More likely you need to step back and review other options.

[BKGUY]

Are you actually going to use all 1.00" of the flutes or do you just need to reach into a part 1.00" deep? A necked tool with a short LOC would be much stronger than a tool with 1.00" of flutes. Just my opinion.:idea:

[handlewanker]

Hi, you must be joking.....in 4140....wow.

I'd spark erode it.....even grinding with a mounted stone would give you headaches.

Actually, without seeing the shape of the job, (and a photo does wonders), you could use a slotting operation as used on the back of a Bridgeports' ram if'n you can get one, and this will allow you to plunge down to an exact depth with a tool like a chisel etc.
Ian.

[DMF_TomB]

I am looking for End Mills for a specific milling application and I will need them to be able to cut with a depth of at least 1 inch to finish the inside of a piece I am working on.
a 1/8" End mill that can cut 4140HT with a cutting depth of at least 1" is needed.

parameters
1/8" diameter carbide end mill
1" flute length
cutting 4140 steel
.
my calculations show at 1.1" stick out from collet a 1/8" diameter carbide end mill will have a safe maximum depth of cut of 0.004"
......push it too hard and end mill will break or at the very least leave a bad finish

[lancut]

With out knowing exactly what are you going to machine, I would strongly suggest a slot cutter mounted either on supported arbor or use short stubby arbor. Hope this helps , Either way good luck.

[txcncman]

You did not specify what finish is required or if a small step is allowable. If possible, consider pre-drilling the corners with at least a 0.120 drill. You probably will also find out that you have to go against conventional machining wisdom to avoid breaking your endmill and reducing chatter by slowing everything way, way down. I am talking 200 RPM or less and 0.5 IPM feed. I would still try it wish recommended speed and feed first. But you will probably write off the first endmill to learning. Also maximum axle depth of cut is probably going to be 1/2 diameter or less.

[DMF_TomB]

I am talking 200 RPM or less and 0.5 IPM feed. I would still try it wish recommended speed and feed first. But you will probably write off the first endmill to learning. Also maximum axle depth of cut is probably going to be 1/2 diameter or less.

the chance of milling 4140 steel with a
1/8" diameter end mill
at 1" stickout of collet
at 0.062" DOC i would rate at <1% it will work
.
the rule is stickout 2x more flexing goes up 2x2x2 or 8 times
stickout 3x more flexing goes up 3x3x3 or 27 times
.
thats one of those rules of the universe. doesn't matter if you do not like it. long end mills on hard materials behave 1000% different than short end mills on aluminum