deep hole drilling

[Chappy2]

A part I am running requires drilling (3) .078 dia holes 1.8 deep.
Mat'l is cast 420f s.s.

Live tool through coolant is not an option.
I am currently using a G83 peck cycle with full retract to clear chips.
per peck length = .078 RPM=3000 Feed= 4.3 IPM.
Drill is cobalt TIALN coated parabolic flute.
Machine is a Murata MW200 twin spindle lathe
There is no room on the turret for another drill to start the hole.
I am using a .125 spot drill for centering.
Although this process works ,it is somewhat time consuming.
Other than increasing the peck length , does anyone have any experience or advice drilling small holes this deep.
I appreciate any input,suggestions,or methods.

 

[Pressed]

There is an EDM machine that can drill holes like that. Some people call them EDM Drills, others hole poppers, while others call them Plunge EDM's; the last term is questionable.

There are companies that list those services, I have seen them drill diameters down to 0.015". Looks like a query for google is in order.

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[ornerynorsk]

What kind of qty are you talking about? If you've got a lot of parts to deal with, you should talk to a gundrilling company.

 

[CSLufkin]

We used to use what we called a W drill. It had a W shaped point on the end, but it was some time ago. I don't remember much more tham that, sorry.