Just an update on what happened with drilling all those holes. We ended up using Dormer drills, CDX-Al. Mostly because of availability. Coolant thru. The part was redesigned and we had to go thru 0.375" with about 36,000 holes and 1.7" thru ribs (0.875" from both sides) with over 3000 holes. Short drill 125 IPM no pecks. Broke two longer drills trying different things like changing feeds and different pecking. Finally we bought super long (8D) CDX-Al drill and used it at 70 IPM no pecks. Below are couple of videos, one drilling shallow holes and second deep holes. Jerry
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