Drilling Op Longer than stroke

By Michal Orzechowki
This customer project required drilling 6.5” when the machine stroke was only 5.2”. Our solution was to make a custom short projection coolant through holder and change machine parameters to allow additional stroke. Sorry we can’t show you the part, but the process was fun!

Normally drilling sleeves for back 8-spindle unit T21 – T28 are at least 1.5” long. We required a drill sleeve sticking out from the face of back gang max. .500” to gain more drilling stroke so we custom made coolant thru holder for a drill basically by boring drill holding diameter in a flange with coolant thru holes. It gave us additional over an inch stroke.

Next step was changing Z+ over travel limits and D values assigned to them to the values allowing sub spindle get as close to end of drilling position as needed.
If anybody is interested about changing overtravel limits we have procedures and we can send them by request.