[AKcrabber]

i just started this job and the are all about plunging out large amounts of stock. the thing is, HY-80 (and HY-100) are high nickel content alloys and they just tear up inserts. most of the machinists here dont know jack about feeds and speeds and it just got to the point where they used up 40 inserts plunging out this crap all within a week.

not the manufacturing guy has told me to go with indexable drills.

i dont think he understands that it is not ideal to go this route.

so what should i recommend? continue plunging with different feeds and speeds, humor him with the indexable drills, or try another manner altogether.

i havent work with alot of these crazy alloys before and am just looking for a little direction

thanks.

[78nova]

I am not familar with this type of material but I may be able to help with some ideas or thoughts. I am cutting 15-5 stainless @ 34-38 RC.

First off, it will help if I have more information.

What brand & size of cutter are you currently using? How many inserts?

What is the insert grade?

Are these pocket plunge cuts or through cuts?

How much are you stepping over?

What is your current feed and speed & cycle?

Are you running dry or with coolant?

If using coolant, is it oil or water soluble?

You said that using a Kubit style insert drill is not ideal. Is it the shape of the part that does not lend to this?(nuts)

[AKcrabber]

Not sure on the brand of cutter, but it is a 2" plunge mill.

Using Seco clear coated inserts. not sure on the grade

Plunges are going all the way through 4" stock around perimeter....stepping over .25

250 Rpm 6.0 Inches per minute, is what the old programs was far. doubt the operator is running it like that

running it with water soluable coolant.

[78nova]

Are the inserts carbide & how many in cutter? What shape & radius?

I do not believe I have heard of a clear coated insert.

.250 step over is a big cut.

Is the tool you are using actually designed for plunge cutting?

Can you try modifying the program stepover along with the feed & Speed?

I am running a 3.0" Iscar cutter with 6 carbide coated inserts.

I am stepping over .100, 412 rpm @ 31 ipm, no coolant.

My cuts are 4.0" deep on one side, stepping over .100 until reaching about 1.250 over into part and they are pocket cuts. The other pocket cut is about 3.0" deep and about 1.0" wide.

My part is square and is 3.0" wide. I position in X, Y & Z and make my first cut 1.2" above center, second cut is 1.2" below center, third cut is on center.
This leaves two ridges that after I reach my X finish position I then Change my Y positon & plunge down across the two ridges.

I was making my off center cuts @ 1.5" above and below center. Moving the cutter .300 made a big difference as to how the insert enters the material on those first two cuts.

Can you explain what the pattern is you are cutting?

After the tool has made its first complete pass, Through your 4.0" cut, how much is the tool moving over in X & Y?

Kenny

[knudsen]

Get a big book from MSC or check the on-line version, they have charts that tell what coating is best. Looks like TiCN is best for conventional mills, I didn't look up the inserts.

[universalfab]

i just started this job and the are all about plunging out large amounts of stock. the thing is, HY-80 (and HY-100) are high nickel content alloys and they just tear up inserts. most of the machinists here dont know jack about feeds and speeds and it just got to the point where they used up 40 inserts plunging out this crap all within a week.

not the manufacturing guy has told me to go with indexable drills.

i dont think he understands that it is not ideal to go this route.

so what should i recommend? continue plunging with different feeds and speeds, humor him with the indexable drills, or try another manner altogether.

i havent work with alot of these crazy alloys before and am just looking for a little direction

thanks.

I also am not familiar with that material, but we do work with inco, other exotic hard to machine materials, and alot of stainless steel alloys. We machine most of it and that is just the fact of the matter your going to go through cutting tools. You can mess around with different endmills, but your still going to eat them up. Your best bet if you have the means of doing so are EDM. I have a buddy that works at honeywell and he works in the department where they make jet turbines and they go through I think he said like 40 tools every hour on just the 2-3 machines he's running "possibly just each machine I don't quite remember" and I think it's like 400 tools a day. When machining these materials there really is no way around the tool consumption, unless the parts can be made using a different method. If the cutter isn't completely annialated I would definately recommend your shop getting a endmill sharpener if you don't already have one, it might be able to help cut down on some expenses. Good luck

[jamesu229]

A mitsubishi feedmill will handle this with no probem. We use them for plunging and the inserts are relatively cheap.