Optical Center Punch ?

I own a Skidmore OCP. Very well made. I like it ok, except that the magnet, obviously, won't work with non ferrous metals, so I may make a new base for the punch and optic. The prick punch with intersecting scribed lines works well enough..with my magnifying eye glasses. I rarely use the OCP.
 
Last edited:
I noticed that the Flexbar version comes with two punches, a 60° and a 120°. When would someone use the 120° punch?
 
When would someone use the 120° punch?

Actually I would prefer the 120 degree punch!
(that is, if going directly from this punch operation to the drilling operation.)
Since most of my drill bits are 118 degrees, they would find centre better in the 120 degree divot.
The drill bits' centre would nestle perfectly into the punch centre before the lips make contact.

By using the 60 degree point, the typical 118 degree bit would contact away from its' centre and possible chatter and wander.

-brino
 
Actually I would prefer the 120 degree punch!
(that is, if going directly from this punch operation to the drilling operation.)
Since most of my drill bits are 118 degrees, they would find centre better in the 120 degree divot.
The drill bits' centre would nestle perfectly into the punch centre before the lips make contact.

By using the 60 degree point, the typical 118 degree bit would contact away from its' centre and possible chatter and wander.

-brino

I would have thought that the proper order would be to center punch, center drill, then drill to size (whether stepped or not). Or, let the previous operation guide the next, thus keeping layout/wandering errors at a minimum.
 
Back
Top