[Bryfisher]

Hi all

We have a large run of counterbores to do in 1045 and 4140. Problem is they are BLIND counter bores. 1" dia, 2" deep plus Running a old mazak with a double table pallet / bed tipped. 001 per inch in x / cat40 holders

What's my best option for speeds & feeds

Thanks in advance all,

[ToolHIT]

With Blind Counterbores I have had the best luck coming in with an Indexable Drill that would give you near a flat bottom and then cleaning up with a Necked End Mill to give you the flat bottom counterbore you need. Here are the 2 tools I'd recommend:

Tool 1: Kyocera 1" Diameter 2XD Coolant Thru Indexable Magic Drill
Run at 500 SFM and .0045" IPR. (8.6 IPM)
This is available in a Kit that includes the Drill Body and (10) Insert with 4 Cutting Edges per Insert. This Drill uses the same insert for the inboard and outboard pockets and gives you near a flat bottom (you will want to leave about .030"-.050" at the bottom of the hole for the End Mill to Clean up), here is an image of the drill profile at the bottom of the hole:

Tool 2: 3/8" Diameter x 1/2" LOF x 2-1/8" Neck Length x 4 Flute APLUS Coated Variable Pitch End Mill
This Tool is necked back to give you the clearance you need to come in and clean up bottom of the bore and give you a flat bottom
Run at 300 SFM and .0018" CLPT (3,056 RPM and 22 IPM)

Hopefully this helps!

Mike

[Bryfisher]

Thank you so much...I have passed the info off and was kicked in the N@TS. this ""ISO"" and programmers not knowing much is killing me. Unfortunately I cant use 2 tools. I know sounds dumb right. "Standard" has been set can only use 1 tool.

[ArtHeatSign]

You can calculate the speed with this simple formula:

RPM=SFPM*3.82/CUTTER DIAM.


Since 1045 and 1040 are medium Carbon steel their SFPM value is the range of 200-250

For the feeds, I'd suggest 0.10 inches per revolution. That'd work well with 1045 & 1040.

Try using these values and give me a feedback.

Thanks.

[generaldisarray]

You can calculate the speed with this simple formula:

RPM=SFPM*3.82/CUTTER DIAM.


Since 1045 and 1040 are medium Carbon steel their SFPM value is the range of 200-250

For the feeds, I'd suggest 0.10 inches per revolution. That'd work well with 1045 & 1040.

Try using these values and give me a feedback.

Thanks.

.1 per rev huh? Sound a little grunty,

Id like to see that operation, but only if you have some of those Mythbusters blast shields.

[ArtHeatSign]

I found info from the file below.
https://www.heatsign.com/wp-content/...-and-feeds.pdf