Thread: Drill bits
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Old 2nd Mar 2019, 9:27 pm   #29
Station X
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Default Re: Drill bits

Centre punching is part of the marking out process so that the hole is drilled in the right place. It's difficult to feed a drill down to the precise interscection of two scribed lines, but very easy to centre punch the intersection and feed into that. Just rest the centre punch in one scribed line and slide it along until you feel it drop into the other one.

If you're not going to use a centre punch it's better if you use a proper spotting drill, which is what I use in my CNC milling machine.

Centre drills are intended for drilling centres in lathe work pieces intended to be mounted between centres. All to easy to break in my opinion unless your lathe has a lever feed tail stock. A screw fed tail stock is like using a screw type car jack and has no "feel".
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