I start by chucking the joiner in my drill and using a metal file to remove material quickly.

This is plumbers emery, found in the home stores plumbing section. This will polish up the surface.

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1/8 piano wire grinded to a point. This is only to mark the center panel. I use blunt pins for normal operation.

I drill alignment pins towards the TE, here I'm using a nail to make a mark so the drill does not wander.