A less expensive tool would be a end mill. These look like a short drill bit
without a taper on the cutting edge. The Import stuff isn't too bad, a 1/2
end mill is
~ 15.00. USA made stuff is 40 + .
Counter bores look similar but have interchangeable pilots that add to the
cost.
I use end mills in a drill press to clean up parts with broken bolts.
Frequently the bolt will break at the surface of the part. This leaves a
ragged
edge making it more difficult to center drill the bolt and remove. Use a end
mill slightly larger than the bolt to make a smooth flat surface.
If you can't find a end mill, resharpening a drill bit to cut flat would
work, just be sure to drill the hole with a regular bit first.
When you tap the holes, get a starting tap ( long taper ) this makes things
much better as you will be able to cut a thread freehand. Most of the taps
sold are plug taps ( short taper ) these are more for cleaning up a existing
hole. There are also bottoming taps ( no taper ) that are for blind holes.
Try www. kbctools.com they are good to deal with.
I used to get stuff from Enco, but I think they have been bought my MSC tools.
Harold
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