What's new
What's new

Deep Hole Drilling in SS303 on a VMC

eopin

Plastic
Joined
Oct 24, 2019
Hello all,

We are working on a project where the part feature requires deep-hole drilling as per the below-mentioned details:
Material: SS303 Stainless Steel
Drill Diameter: 0.125" +/- 0.005"
Drill Depth: 2.64"
900 holes for trial batch

Our tooling is as follows:
HSK A50 Spindle with 15 bar Thru Coolant (1.5 MPa)
Schunk Tendo P Holders (Hydraulic)

Can anyone suggest a good drill tool for the application? We are looking for maximum tool life and the lowest cost per component parameter primarily.
So far we are studying across the companies like Mikron, Walter, Guhring, Kennametal, Hitachi Moldino, and OSG.

Any input or experience is appreciated. We are working on such a feature for the very first time.
 
Only 15bar could be a problem, but at least 303 cuts nicely.
Agreed. 15bar is 218psi. It will help with cooling but not so much with chip evacuation. You might have to peck.

I use and am happy with Mitsubishi MVS drills.

You'll need to drill a starter hole with the same or slightly numerically larger tip angle. Hand program the long drill to enter the starter hole at around 5000RPM at 5IPM to within about .010" of the starter hole bottom. Then ramp up to your drilling RPM and drill your hole to depth. You can program your pecks (if need be) to NOT come all the way out of the hole so the drill is always supported.

When done with the hole, rapid up to within maybe .050" of the top, slow the RPM back down, then rapid out and on to the next hole.
 
Agreed. 15bar is 218psi. It will help with cooling but not so much with chip evacuation. You might have to peck.

I use and am happy with Mitsubishi MVS drills.

You'll need to drill a starter hole with the same or slightly numerically larger tip angle. Hand program the long drill to enter the starter hole at around 5000RPM at 5IPM to within about .010" of the starter hole bottom. Then ramp up to your drilling RPM and drill your hole to depth. You can program your pecks (if need be) to NOT come all the way out of the hole so the drill is always supported.

When done with the hole, rapid up to within maybe .050" of the top, slow the RPM back down, then rapid out and on to the next hole.
A lot of folks spin the drill backwards when entering a starter hole to prevent chipping the drill. I have done it both ways and never really had an issue.
 
Did you accidentally add an extra zero in there?
No sir. I've been running that first move at S5000 for years. My largest drill I do this with is .086" 25xD, so it's in the ballpark of his .125" drill. Runout matters though. If you've got a runout issue at all, I would definitely slow this initial plunge down.
 








 
Back
Top