Deep drilling annealed 440c

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Chrispy87

Plastic

Joined

Aug 4, 2021

• Aug 4, 2021

• #1

Hey guys I'm looking for deep hole drilling advice. I need 90+ holes through annealed 440c. 1.800" depth, 5/64 diameter. (Yes that's like 24xD I know.) Drilling is done in a HAAS TM1P using a HSS jobber length bit.

Currently drilling half way and flipping to drill backside. They don't have to line up perfectly for our application they just need to exist.

Wondering how others with more experience would attack this to drill it without setting it up twice.

 

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cunaf85

Plastic

Joined

Mar 1, 2019

• Aug 4, 2021

• #2

Walter offers up to 40xD solid carbide drills, not sure as to if they carry one that suits your application. We do hundreds of 25xD holes everyday in H1000 15-5. Spot, Pilot, Thru Coolant and blast all the way to the bottom without pecking.

 

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Chrispy87

Plastic

Joined

Aug 4, 2021

• Aug 4, 2021

• #3

Wish I had a through coolant spindle! That would definitely make my life easier.

 

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cunaf85

Plastic

Joined

Mar 1, 2019

• Aug 4, 2021

• #4

We use a similar ratio HSCO drill, but I can't remember how deep the hole actually is.

 

mhajicek

Diamond

Joined

May 11, 2017

Location

Maple Grove, MN, USA

• Aug 4, 2021

• #5

You can get a coolant inducer to plumb your coolant through the tool. Failing that, just get some decent cobalt drills, replace when dull.

 

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HuFlungDung

Diamond

Joined

Jan 19, 2005

Location

Canada

• Aug 4, 2021

• #6

Haas has some G72 high speed drilling cycles you can take advantage of. If doing conventional peck drilling, those high speed cycles can make a big difference in drilling rapidly for the first 3/4 inch while the chip flow is good, and then the pecking can start. I'd peck at about 1xD per peck, and withdraw to clear. Sometimes might peck 2 or 3 times with only a chip break move before a full retract, but that would be when there is enough room in the drill flutes for 2 or 3 parallel chips to form. Aggressive enough feed is critical to get a chip that flows up the flute, instead of creating a crumbly flute packing mess.

 

Mechanola

Stainless

Joined

Mar 21, 2011

Location

Äsch

• Aug 5, 2021

• #7

Another waterjet case?

 

hvnlymachining

Hot Rolled

Joined

Jun 21, 2019

Location

St.Onge

• Aug 5, 2021

• #8

I hate pecking when avoidable, just too hard on finish, tools and time. after my first coolant through drill I wondered how I lived without them. Now I have an adapter and coolant system for nearly every machine that can drill. High pressure coolant works best and is worth the trouble setting up. However I should mention most of the deeper (over 5xD) holes I drill are over 1/2" dia. And usually on manual machines. But if I go deep, I go coolant through whenever possible. Good luck.

 

Mtndew

Diamond

Joined

Jun 7, 2012

Location

Michigan

• Aug 5, 2021

• #9

Chrispy87 said:

Wish I had a through coolant spindle! That would definitely make my life easier.

Click to expand...

Since you don't have thru spindle coolant, I'd get a good parabolic drill so you don't have to peck as much.