I am new to running Spade Drills. The guy training me is...... clueless.
I am running 4" to 6 1/2" spades up to 40" deep, into 4140. In an old and worn out boring mill.
The tool has thru coolant, but in my opinion, not enough. After about 18" deep, chip evacuation becomes an issue. The chips just get ground up. And I suspect cause the spade to get stuck in the bore. It has happened several times.
Do you need a small pilot drill to start? A Center Drill mark? The material is sawcut and fairly square. From time to time, the Drill does seem to bounce when starting. I have been drilling a pilot hole just slightly smaller than the chisel tip on the spade. Usually, 3/16".....ish. I'm starting to wonder about pilot drilling.....
I can't seem to get more than 40 - 45 sfm and 0.004" ipr. Does this sound normal?
Thanx for any info you all can give me.
I am running 4" to 6 1/2" spades up to 40" deep, into 4140. In an old and worn out boring mill.
The tool has thru coolant, but in my opinion, not enough. After about 18" deep, chip evacuation becomes an issue. The chips just get ground up. And I suspect cause the spade to get stuck in the bore. It has happened several times.
Do you need a small pilot drill to start? A Center Drill mark? The material is sawcut and fairly square. From time to time, the Drill does seem to bounce when starting. I have been drilling a pilot hole just slightly smaller than the chisel tip on the spade. Usually, 3/16".....ish. I'm starting to wonder about pilot drilling.....
I can't seem to get more than 40 - 45 sfm and 0.004" ipr. Does this sound normal?
Thanx for any info you all can give me.