Countersinks, Reamers & Burs

500+ products

Expected delivery: Wed, Nov 18

These tools finish a hole or edge after drilling. Countersinks cut a cone so flat head screws sit flush and also break sharp edges. Reamers bring a drilled hole to an exact size with a smooth finish for pins, bushings and shafts. Carbide burs shape, deburr and port metal in a die grinder. This section includes single flute, multi-flute and zero flute countersinks, chucking reamers, hand reamers and adjustable reamers, carbide burs in common shapes and cuts, and hand deburring tools.

What to check before you order

• Countersink angle. Match the screw head. Inch flat head screws generally use 82 degrees, metric flat heads use 90 degrees, and some aircraft fasteners use 100 degrees.
• Reamer allowance. Drill the hole slightly under the finished size before reaming. Reamers remove only a small amount of stock.
• Bur shape and cut. Cylinder, ball, tree and flame shapes reach different areas. Double cut burs leave smaller chips and a smoother finish on steel. Single cut suits hard steel and general stock removal.
• Shank and speed. Most burs have a 1/4" or 1/8" shank. Stay within the bur maker's speed rating and wear eye protection.

Browse drill bits, end mills and inserts, Alfa Tool countersinks and reamers, or all cutting tools.

Common questions

What is the difference between a chucking reamer and a hand reamer?

A chucking reamer runs in a drill press, lathe or mill at reduced speed. A hand reamer has a square end for a tap wrench and a longer tapered lead so it can start straight by hand.

Can carbide burs be used on aluminum?

Yes, but standard cuts can clog with soft metal. Aluminum-cut burs have coarse, widely spaced flutes that clear chips better on nonferrous metals. Follow the bur maker's speed guidance and wear eye protection.

Countersinks, Reamers & Burs: page 9

• Approved Vendor 3/8"-120 HSS Single Flute Countersink SKU 22372 $11.61
• Approved Vendor 3/8"-120 HSS Single Flute Countersink (2) SKU 22373 $8.95/pack of 2
• Approved Vendor 3/8"-60 HSS 3 Flute Center Reamer SKU 22760 $8.67
• Approved Vendor 3/8"-60 HSS 6 Flute Chatterless Countersink SKU 22761 $12.55
• Approved Vendor 3/8"-60 HSS Single Flute Countersink SKU 22762 $11.61
• Approved Vendor 3/8"-60 HSS Single Flute Countersink (2) SKU 22763 $8.95/pack of 2
• Approved Vendor 3/8"-82 HSS 3 Flute Center Reamer SKU 22767 $8.67
• Approved Vendor 3/8"-82 HSS 6 Flute Chatterless Countersink SKU 22768 $12.55
• Approved Vendor 3/8"-82 HSS Single Flute Countersink SKU 22769 $11.61
• Approved Vendor 3/8"-82 HSS Single Flute Countersink (2) SKU 22770 $8.95/pack of 2
• Approved Vendor 3/8"-90 HSS 3 Flute Center Reamer SKU 22771 $8.67
• Approved Vendor 3/8"-90 HSS 6 Flute Chatterless Countersink SKU 22772 $12.55
• Approved Vendor 3/8"-90 HSS Single Flute Countersink SKU 22773 $11.61
• Approved Vendor 3/8"-90 HSS Single Flute Countersink (2) SKU 22774 $8.95/pack of 2
• Alfa Tool 3/8-2 Plumber's Reamer SKU MR54577 $65.42
• Approved Vendor 3/A HSS Adjustable Reamer 13/32" - 7/16" SKU 23375 $41.07
• Alfa Tool 31/32 HSS Chucking Reamers SKU CR54060 $66.58
• Approved Vendor 31/32" HSS Straight Flute Hand Reamer SKU 23412 $100.29
• Approved Vendor 31/32" HSS Straight Shank Machine Expansion Reamer SKU 23413 $134.48
• Approved Vendor 31/32" HSS Taper Shank Machine Expansion Reamer SKU 23417 $145.00
• Approved Vendor 31/32" X 3/16" HSS Aircraft Counterbore 1/4" Shank SKU 23424 $80.70
• Approved Vendor 31/32" X 5/16" Pilot Hole HSS Straight Shank Counterbore SKU 23425 $71.66
• Approved Vendor 31/64" X 3/16" Pilot Hole HSS Straight Shank Counterbore SKU 23476 $41.77
• Approved Vendor 33/64" X 3/16" Pilot Hole HSS Straight Shank Counterbore SKU 23535 $47.03
• Approved Vendor 35/64" HSS Straight Flute Hand Reamer SKU 23574 $53.47
• Approved Vendor 35/64" X 3/16" Pilot Hole HSS Straight Shank Counterbore SKU 23584 $48.93
• Approved Vendor 37/64" X 3/16" Pilot Hole HSS Straight Shank Counterbore SKU 23632 $51.28
• Approved Vendor 39/64" X 3/16" Pilot Hole HSS Straight Shank Counterbore SKU 23667 $51.28
• Approved Vendor 5/32" HSS Straight Flute Hand Reamer SKU 25410 $28.01
• Approved Vendor 5/32" X 1/8" Pilots for Counterbore SKU 25421 $6.98
• Approved Vendor 5/32" X 3/32" Pilots for Counterbore SKU 25432 $6.98
• Approved Vendor 5/8" HSS 1/2" Straight Shank Bridge Reamer SKU 25605 $69.89
• Approved Vendor 5/8" HSS 2MT Straight Flute Bridge Reamer SKU 25607 $65.41
• Approved Vendor 5/8" HSS Black & Gold 1/2" Straight Shank Bridge Reamer SKU 25609 $73.38
• Approved Vendor 5/8" HSS Straight Flute Hand Expansion Reamer SKU 25622 $182.80
• Approved Vendor 5/8" HSS Straight Flute Hand Reamer SKU 25623 $56.78
• Approved Vendor 5/8" HSS Straight Shank Machine Expansion Reamer SKU 25624 $87.38
• Approved Vendor 5/8" HSS Taper Shank Machine Expansion Reamer SKU 25629 $97.11
• Approved Vendor 5/8" X 1/2" Pilots for Counterbore SKU 25674 $14.92
• Approved Vendor 5/8" X 1/4" Pilots for Counterbore SKU 25676 $14.92
• Approved Vendor 5/8" X 1/8" HSS Aircraft Counterbore 1/4" Shank SKU 25677 $52.09
• Approved Vendor 5/8" X 3/16" Pilot Hole HSS Straight Shank Counterbore SKU 25711 $46.26
• Approved Vendor 5/8" X 3/16" Pilot Hole HSS Taper Shank Counterbore SKU 25712 $46.60
• Approved Vendor 5/8" X 3/16" Pilots for Counterbore SKU 25713 $14.92
• Approved Vendor 5/8" X 3/8" Pilots for Counterbore SKU 25716 $14.92
• Approved Vendor 5/8" X 5/16" Pilots for Counterbore SKU 25724 $14.92
• Approved Vendor 5/8" X 7/16" Pilots for Counterbore SKU 25750 $14.92
• Approved Vendor 5/8"-100 HSS 3 Flute Center Reamer SKU 25761 $16.50

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