Solid tungsten carbide burrs ground from the solid in Saginaw, Michigan since 1931. Single cut, double cut, and super coarse aluminum cut, in every industry-standard shape.
Find a Distributor Download CatalogA carbide burr (also called a rotary file or rotary burr) is a small cutting tool with a solid tungsten carbide head, driven at high speed in a die grinder, pencil grinder, flex shaft, or CNC spindle to deburr, chamfer, shape, and blend metal.
Severance introduced the precision-ground rotary file in 1931 under the Midget Mill® name. Every carbide burr we make today is still ground from the solid, never stamped or pressed, in our Saginaw, Michigan plant. Carbide holds a sharp edge at higher speeds and temperatures than high-speed steel, and in most applications a carbide burr delivers five to ten times the service life of the equivalent HSS rotary file. When the edge finally dulls, our regrind service restores it.
Need high-speed steel instead? See our H.S.S. rotary files, or compare the two materials in HSS vs Carbide.
Severance grinds four carbide tooth patterns. The material you are cutting and the finish you need decide which one to order.
| Cut | Severance line | Best for | Chip and finish |
|---|---|---|---|
| Single cut (spiral flute) | Carbide Midget Mills® (1/4" shank) Ecarno-Mills™ (3/32", 1/8", 3/16" shanks) |
Steel, stainless, cast iron, and hard alloys. General deburring, chamfering, and finishing. | Longer chips, smoother finish, more control on edges. |
| Double cut | Carbo-Mills™ (1/4" shank, plus 3/32" to 3/16") | Heavy stock removal on ferrous, non-work-hardening materials. The double cut pattern was first introduced by Severance. | Small chips, faster cutting, less grabbing. Rough to medium finish. |
| Super coarse (aluminum cut) | Sever-Cuts™ (1/4" shank) | Aluminum, brass, copper, zinc die castings, magnesium, and plastics. | Wide open flutes that do not load. Aggressive removal, medium finish. |
| Fine double cut | Di-Car Mills™ and Bore-Mills™ | Light stock removal where a very good finish is required. Replaces mounted grinding wheels in die and jig work. | Very fine chips, grinding-wheel quality finish. |
| Plastic deburring | d-burrs™ (1/4" shank) | Finishing plastic parts without melting or tearing. | Severance EFHB cut for fine finishing of plastics. |
Most catalogs identify carbide burr shapes with the SA to SN codes. Severance shape letters predate that convention, so use this table to cross-reference from any competitor's part number. The Ecarno-Mills™ line is named directly with the standard codes; the Midget Mill® shape pages list every diameter, flute length, and EDP number.
| Standard code | Shape | Severance Midget Mill® shape | Ecarno-Mills™ part (3/16" shank) |
|---|---|---|---|
| SA | Cylinder, plain end | Shape A | SA-81 (EDP 21921) |
| SB | Cylinder, end cut | Shape A-EC (end cutting) | SB-81 (EDP 21923) |
| SC | Cylinder, ball (radius) nose | Shape C | SC-81 (EDP 21927) |
| SD | Ball | Shape B | SD-81 (EDP 21925) |
| SE | Oval (olive) | Shape Q | SE-81 (EDP 21928) |
| SF | Tree, radius nose | Shape R and Shape S | SF-81 (EDP 21929) |
| SG | Tree, pointed nose | Shape T | SG-81 (EDP 21930) |
| SH | Flame | Shape FL | SH-81 (EDP 21933) |
| SL | Taper (cone), 14° included angle | Shape L | SL-81 (EDP 21931) |
| SM | Cone, pointed nose | Shape J (other taper angles: Shapes E through M) | SM-81 (EDP 21932) |
| SN | Inverted cone | Shape N | SN-81 (EDP 21934), SN-82 end cutting (EDP 21935) |
Cross-reference taken from Severance Catalog 101, Carbo-Mills™ and Ecarno-Mills™ page. Midget Mills® are also ground in shapes with no industry equivalent, including Shape D, Shape P (pear), Shape U (concave), Shape V (convex), Shape W, Shape X (double angle), and Shape BI (bi-convex). See the full Midget Mill® shape list.
Carbide burrs run faster than HSS rotary files. Use the carbide RPM chart on our speed and feed page, start at the low end for small heads in hard material, and let the tool cut with light pressure. Forcing a carbide burr builds heat and chips the edge.
Not sure which shape to start with? The tool selection guide walks through it by job.
Carbide Midget Mill® sets bundle the most-used shapes in one case, a practical way to equip a bench or a service truck. Junior Mill®, Lab Mill™, and Di-Car Mill™ sets cover miniature and finishing work.
They are the same family of tool. Rotary file is the traditional name Severance used when it introduced the precision-ground Midget Mill® in 1931; burr is the name most machinists use today. In practice, high-speed steel versions are usually called rotary files and solid carbide versions are usually called carbide burrs. Both are ground from the solid at Severance.
Single cut (spiral flute) burrs such as carbide Midget Mills® and Ecarno-Mills™ take longer chips and leave a smoother finish, which suits general deburring and finishing on steel, stainless, and cast iron. Double cut Carbo-Mills™ add a second set of flutes that break the chip into small pieces, cut faster, and grab less, which suits heavy stock removal on ferrous, non-work-hardening materials where a rough to medium finish is acceptable.
Sever-Cuts™ super coarse carbide burrs. Their wide, open flutes clear soft, gummy chips so the tool does not load up, which is the usual failure of a standard-cut burr in aluminum, brass, copper, zinc, and magnesium.
Carbide Midget Mills®, Carbo-Mills™, and Sever-Cuts™ have 1/4 inch shanks for standard die grinders. Junior Mills® have 1/8 inch shanks and Lab Mills™ have 3/32 inch shanks for pencil grinders and flex shafts. Ecarno-Mills™ and small Carbo-Mills™ are available with 3/32, 1/8, and 3/16 inch shanks, and long shank Midget Mills® have a 1/4 inch shank that is 8 inches long.
Yes. Every Severance carbide burr and rotary file is ground from the solid at the Severance Tool Industries plant in Saginaw, Michigan, where the company has manufactured since 1939.
Yes. Severance regrinds carbide and high-speed steel rotary files of any brand from 1/16 to 3 inch diameter, typically saving up to 70 percent compared with buying new, with a 1 to 3 week turnaround.
Every Severance carbide burr is stocked by industrial distributors across the USA and Canada. Find the EDP number on the product page, then order from your distributor or ask us for a quote on a special.
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