bottoming drill

bottoming drill

[′bäd·əm·iŋ ‚dril]
(design engineering)
A flat-ended twist drill designed to convert a cone at the bottom of a drilled hole into a cylinder.
References in periodicals archive ?
Tenders are invited for Supply Of 8.5mm Drill Make:Addission,Hss Hand Tap Drill Set For Size: M4x2.5mm.(Set Includes Taper Drill,Second Drill, Bottoming Drill,But Size:M6x2.5mm,But Size:M8x2.5mm,But Size:M10x2.5mm.
Next, we'll switch to a bottoming drill, still of the tap drill size, which cuts a flat bottom hole instead of the usual 135 degree cone pointed drill which would have drilled a hole closer to the rifling at the center than at the perimeter.
A bottoming drill, which was considered good practice by Mr.