Have you tried a High Performance 4 Flute Carbide Drill yet?
If the Spade Drill is all you have then I would try Hu's and Dertsaps suggestions. Bigger Drills like Heavy Feeds and Slow Speeds. I have been told in the past not to Peck with Spade Drills, but to drive straight through uninterrupted. This could be wrong of coarse but I have little experience with Spade Drilling. The places I work are too Old School when it comes to Modern Tooling, LOL.
Toby D.
"Imagination and Memory are but one thing, but for divers considerations have divers names"
Schwarzwald
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)
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