Center drill bits are used to drill accurate center holes prior to turning. They are also used as a starter bit to make accurate holes in stock. These bits are self-centering and match lathe centers. Center bits are usually made of HSS and have a two-part tip with a small pilot and the larger countersinking area. Read our review to choose the best tool for your needs.
1, 2, 3, 4 and 5, 60° tip angles
|Top Quality center bits, M2 HSS|
Drill accurate center holes in material prior to turning, or use as a starter bit for accurate holes
Cutting diameter of the bits:
UGS = US Gauge number size
No. = Engraved number on bit
CN = Closest neighbor
Dia. = Cutting diameter of bit (min/max diam. each end)
OAL = Overall length
Shank = Shank diameter
Drills individually packaged in plastic end mill sleeves and then heat sealed into one pouch. Well ground drills and a value in price. The drills work excellent, nice and sharp. Work fine for steel, aluminum, and other soft materials. Hardened and stainless still are too tough for them.
|This set entirely complies with USAS B94.11-1967 “USA Standard Combined Drills and Countersinks, Plain and Bell Types” by listing #1 as 1/8″ and #5 as 7/16″.|
Size #1 Drill Point Dia. and Lg. : 3/64″ = .047″ = 1.191 mm
Body (Shank) Dia. : 1/8″ = .125″ = 3.175 mm
OAL : 1-1/4″ = 1.250″ = 31.750 mm
Size #2 Drill Point Dia. and Lg. : 5/64″ = .078″ = 1.984 mm
Body (Shank) Dia. : 3/16″ = .188″ = 4.763 mm
OAL : 1-7/8″ = 2.125″ = 53.975 mm
Size #3 Drill Point Dia. and Lg. : 7/64″ = .109″ = 2.778 mm
Body (Shank) Dia. : 1/4″ = .250″ = 6.35 mm
OAL : 2″ = 2.000″ = 50.80 mm
Size #4 Drill Point Dia. and Lg. : 1/8″ = .125″ = 3.175 mm
Body (Shank) Dia. : 5/16″ = 0.313″ = 7.938 mm
OAL : 2-1/8″ = 2.625″ = 66.675 mm
Size #5 Drill Point Dia. and Lg. : 3/16″ = .188″ = 4.763 mm
Body (Shank) Dia. : 7/16″ = .438″ = 11.113 mm
OAL : 2-3/4″ = 5.750″ = 146.050 mm
A great center drill set for the casual machinist.
#1 Body Diameter 1/8″ Drill Diameter 3/64″ Overall Length 1-1/2″ 2x #2 Body Diameter 3/16″ Drill Diameter 3/16″ Overall Length 1-7/8″two Size #3 Body Diameter 1/4″ Drill Diameter 7/64″ Overall Length 2″ one #4 Body Diameter 5/16″ Drill Diameter 1/8″ Overall Length 2-1/8″Set of six.
|These HSS double-ended, 60 degree Center Drills are precision-ground. Used for producing center holds in components or work pieces with require machining between centers.|
Good quality center bits, function well. These are pretty basic, no problems so far. No burrs or milling issues.
Size 1: Body Dia. 1/8″, Drill Dia. 3/64″, O.A. Length 1-1/4″Size 2: Body Dia. 3/16″, Drill Dia. 5/64″, O.A. Length 1-7/8″
Size 3: Body Dia. 1/4″, Drill Dia. 7/64″, O.A. Length 2″
|Double-ended HSS Center bits, precision grounded. These are HSS and come with a good edge, better don’t use them on hard steel. Don’t hold an edge terribly long. For home or hobbyist use, they work just fine. If you are a professional buy something else.|
Tip angles: 60°
1/8″ 3/16″ 1/4″ 5/16″ 3/8″
|Plain style 60° angle used for producing center holes in workpieces which require precision drilling or machining between centers.|
It also used for making starter holes to prevent a drill bit from “walking”.
Center and spotting drills are traditionally used to make a conical hole for a lathe center in order to make a starting point for a standard twist drill, designed to prevent the twist drill from walking.
The set is OK but not great. For mild steel and wood they would work great.