[sdiy] What is the name of this tool?

[David Brown]

I use a drill press and I found that a stepped drill is the only way 
to keep my holes perfectly aligned when drilling 1/8" panels.  I 
start with a center punch on the front and drill a small pilot 
hole.  Then I flip the panel and drill from the back with a stepped 
drill.  I found that when using standard drill bits there was a 
tendency in the soft metal for the drill to wander off center.  The 
stepped drill works great and doesn't wander at all.  I wrap a piece 
of tape around it where I need to stop as a guide.

Dave


At 02:17 PM 11/21/2006, John Mahoney wrote:
>At 10:29 AM 11/21/2006, Louis van Dompselaar wrote:
>>I was wondering: can stepped drills actually drill the initial
>>hole or do you need to pre-drill those with something else?
>>As I see some of them have a flat tip...
>
>A flat tip suggests to me -- strongly -- that a pilot hole is required.
>
>I was taught to use a centerpunch to make a dent when drilling into 
>metal. But, I can see where that might not be good if you are using 
>a drill press and the piece is clamped down, because you don't want 
>the bit to bend. (Is there a machinist, here?)
>--
>john
>