Drilling a .12 hole 4.15 deep in 15-5 RC42

[neurosis]

So, the boss is doing another quote. He wants to know how much it would cost to drill a .12 hole 4.15ish deep in RC42 15-5.   

Guhring is the only company that makes a drill 35x deep. 

I told him he's nuts. 

Anyone had any success trying this?   

[Flycut]

Are we talking one of or production?
I've been doing some gun-drilling 3/16Ø in Inconel on the mills lately with great success.

[neurosis]

Are we talking one of or production?
I've been doing some gun-drilling 3/16Ø in Inconel on the mills lately with great success.

4 parts with 1 hole each. 

[RobertELee]

How accurate do you need? Can you use a hole popper?

[neurosis]

How accurate do you need? Can you use a hole popper?

I don't have a drawing in front of me but I assume that it's +/- .010.  It's a grease hole. 

[RobertELee]

I don't have a drawing in front of me but I assume that it's +/- .010.  It's a grease hole. 

I don't know full tolerance specifics of them but I believe a hole popper would be more than capable of doing that. Especially if you predrilled beforehand and just had them push it to depth. Otherwise try the 35x drill, and if it breaks or doesn't work then you can bring in the hole popper to finish. But .12 at 35x seems like it would act like a spaghetti noodle in that material.

[gcode]

So, the boss is doing another quote. He wants to know how much it would cost to drill a .12 hole 4.15ish deep in RC42 15-5. 

Tell your boss he needs to be sharing that crack pipe

[JakeL]

Can't say I've ever done anything quite that deep or in stainless. But Mitsubishi is who we use for carbide drills, and they make a drill that may work MVS0305X35S060 (Ø.120 35xD).

We've also started using Mikron for some of our trickier applications. Looks like 2.CD.400305.XL (Ø.120 40xD) could work.

Of course both of these drills would need a pilot.

[Flycut]

Drill a pilot hole, (make sure it's flat bottom), or make a guide bushing and hit it with a gun drill.
It's slow but it works.

[neurosis]

Tell your boss he needs to be sharing that crack pipe

We've had several jobs that come through the office that should be immediate no-bids. I don't know if he just likes setting himself up to lose money or if he's just testing us. 

When his Dad owned/ran the shop this stuff would never have been a consideration. 

[neurosis]

Anyone ever tried one of these things?

[JakeL]

Anyone ever tried one of these things?

We used a Mikron crazy drill for a Ø.020 20xD hole in aluminum. We pilot drilled it first tho. I can't imagine the holes in the video are very accurate. 

The one thing they told us when we asked about their speeds and feeds (which seemed way to fast for the size of the drill) "if you slow it down when proving out the program you'll probably break it off". We let it run and had no issues.

[neurosis]

We pilot drilled it first tho. I can't imagine the holes in the video are very accurate. 

I'm guessing (almost certain) that the holes in the video are piloted. 

[Flycut]

I'm guessing (almost certain) that the holes in the video are piloted. 

They have to be...

[CNCAppsJames]

Mitsubidhi and Sumitomo are my go to's when going beyond 30xD. When I need to go >50xD I gundrill.

CTS is a MUST.