Machining-Center

Standard machining centers — both VMCs and HMCs — are not designed for deep hole drilling, but they can handle limited work. I’ve used them for shallow deep holes on prototype parts and low-volume production. The main limitations I’ve run into are coolant pressure, guide bushing support, and chip evacuation. Coolant Pressure Limitations Coolant pressure on a standard machining center is usually 300-1000 psi. This is enough for drilling down to about 6mm diameter at moderate depths up to 10:1 L/D. For smaller diameters or deeper holes, a higher pressure system is needed. ...

I use gun drilling attachments for occasional deep hole jobs on machining centers. A dedicated gun drilling machine is better for production work, but an attachment makes economic sense when you only drill deep holes a few times per month. The attachment turns a standard VMC or HMC into a capable deep hole drilling setup for a fraction of the cost. Attachment Types: Spindle-Mounted vs Self-Powered Two attachment types are available and each covers a different application range. ...