Cobalt Steel Drills Super Duty Cobalt Drill Bits for drilling hard metals.
Cobalt Drills are the best choice for stainless steel and other difficult-to-drill alloy applications.
135-degree split-point for quick penetration and reduced walking . M-35 Cobalt steel for increased heat resistance and longer life. Heavy Duty construction.
$16.99
$3.04
$3.13
$3.80
$4.68
$4.36
$5.16
$5.07
$5.11
$6.17
$5.07
$7.18
$7.53
$7.62
$8.11
$10.94
$9.13
$10.38
$15.43
$12.98
$21.28
$18.42
$21.32
$22.26
$111.97
$24.50
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Size (inches)
Decimal Equivalent
Flute Length (inches)
Overall Length (inches)
5/64
.0781
1
2
3/32
.0937
1-1/4
2-1/4
7/64
.1094
1-1/2
2-5/8
1/8
.1250
1-5/8
2-3/4
9/64
.1406
1-3/4
2-7/8
5/32
.1562
2
3-1/8
11/64
.1719
2-1/8
3-1/4
3/16
.1875
2-5/16
3-1/2
13/64
.2031
2-7/16
3-5/8
7/32
.2188
2-1/2
3-3/4
15/64
.2344
2-5/8
3-7/8
1/4
.2500
2-3/4
4
17/64
.2656
2-7/8
4-1/8
9/32
.2812
2-15/16
4-1/4
19/64
.2969
3-1/16
4-3/8
5/16
.3125
3-3/16
4-1/2
21/64
.3281
3-5/16
4-5/8
11/32
.3438
3-7/16
4-3/4
23/64
.3594
3-1/2
4-7/8
3/8
.3750
3-5/8
5
25/64
.3906
3-3/4
5-1/8
13/32
.4062
3-7/8
5-1/4
27/64
.4219
3-5/16
5-3/8
7/16
.4375
4-1/16
5-1/2
29/64
.4531
4-3/16
5-5/8
15/32
.4688
4-5/16
5-3/4
31/64
.4844
4-3/8
5-7/8
1/2
.5000
4-1/2
6
17/32
.531
4-13/16
6-5/8
21/32
.656
5-3/16
7-1/8
BRAND:
Triumph
Type:
Cobalt
I am trying to make a hole for a 5/8" stud in a carbon steel base. Which is the best size of cobalt drill bit to do this task?
parecase parecase
Since you specified a stud I'm assuming you're going to thread the hole. For a 5/8"-11, a 17/32" drill will give about 75% depth of thread. For 5/8"-18, use a 37/64" drill.If you're not going to thread, that is make a through hole, a 41/64" will provide a close fit hole. A 21/32" will give you a free fit.These sizes may be difficult to find, but if Jamestown doesn't stock them they can probably special order them.
BRET M. TERRITO
4.73
Cobalt drill 3/32"
5
Bought several of these expecting them to break or dull quickly, have to admit one bit did the job drilling through a lot of hard steel.Pleasant surprise to be fully satisfied with this purchase.
cjb
Old Saybrook, CT
Very high quality[...]
5
Good product, Quick [...], Fair cost, Good company response. I'm very pleased overall.
Chip
North Idaho
Best for stainless steel
4
I needed to drill additional holes in my SS pulpits. Ordinary HSS drills didn't work for beans. The cobalt drills were the only ones that worked.
Special order items are not stocked and are ordered direct from the manufacturer. They are non-returnable, may take 2-4 weeks, price and shipping charges subject to change.