TOOLING UP

[jeffl]

I am tooling up for a job and I need some cutters to do the following:

1)bore a .500 .750, .752, .883, and a 1.25 hole thru a 1.875 thick plate of 4140 steel.

2)mill/plunge a 2" x 3" x 1" pocket with .750 corner radii and a R.06 at the bottom in 4140 steel.

Any suggestions?

 

I have a credit with Kennametal, so I will be getting all my tooling from them.

[Guest CNC Apps Guy 1]

Positional and roundness tolerances would dictate which method I would use.

[Scott Bond]

Hi

How many parts ?

[jeff]

For boring I use the Iscar Its-Bore system.

That is an excellent boring head that holds tight tolerances.

[G Caputo]

Jeffl

 

The Kennametal rep just gave us a KISR1.50LF2.5-4 (pg 323 - catalog 8040) to try. It's programmed, just waiting on the material. Corner radius inserts go from 1/64" - 5/16". Ramping shows 26 degrees for the 1.00" to 12 degrees for the 1.50". I don't know how well it works yet, but we will soon find out. The parameters he gave were 300sfpm, .008" chip load at .187" depth of cut in 4140 ht, dcf material.

JM2C.

 

Greg

[crazy^millman]

I would think upwards of 450 sfpm might be where you end up. I would be looking to my higher RPM to get into my Torque are of the machine. I think it say 26 but I always tried to stay at 10 seem to clear chips alot better. I would also ask if it should be run dry almost bet it should be.

[robk]

Like Scott said "How many parts?"

 

I swear by Urma MicroMax Adjustable Balance Boring Heads from Command Tooling. Very expensive, but top notch The are balancable up to 20,000 rpm. The inserts last forever with the right speeds & feeds. If you plan on doing production work they are very well worth the money. The steel bars use carbide inserts and have a range of .354-1.575 with the bore depth of 2.953. The carbide bars have a range of .036-.878 with bore depth of 4.528

[jeffl]

I currently have a KIPR125RP43540 that I was going to use to helix down within the pocket and then finish with a 3/4" carbide endmill to clean up the side walls, corners and bottom. I would like to do this with 1 cutter if there was something out there that could plunge and finish the pocket to +/-.0003.

As far as the other holes go, I leaning towards a helix circular interpolation with an endmill.

[Marty A]

well jeff

 

for the pocket i use a tool called dyna shear

with a .o6 rad on the inserts.i would use a

1 inch dyna shear and rough out the pocket

then use your 3/4 carbide with rad on cutter

and fin the walls.don't know how fussy the

rad at the bottom is.hope this helps

 

 

marty

[robk]

quote:

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I would like to do this with 1 cutter if there was something out there that could plunge and finish the pocket to +/-.0003.

---

 

.0003 with one cutter rough & finish?? Crazy talk I tell you. You will leave steps allover the place.