Tube End Chamfering for Weld Prep, Fittings and Hydraulic Lines
How to pick a tube chamfer tool, set the angle, size it to the tube, and run it without damaging thin wall
Why Tube Ends Need a Chamfer
A saw, abrasive wheel, or shear leaves the tube end square and burred. Chamfering does four jobs:
- Weld penetration. A bevel on the OD opens the joint so the arc reaches the root.
- Fitting and ferrule seating. Compression ferrules, flare nuts, and push-to-connect fittings need a smooth OD lead-in and a burr-free end face.
- Hose and O-ring safety. A burr as small as 0.003″ can nick an O-ring during insertion (see our tube deburring guide). An inside chamfer gives the seal a ramp.
- Burr removal before flaring or bending. A burred end splits the flare.
In hydraulic lines running 3,000 to 10,000 PSI, a loose burr fragment can score a cylinder bore or jam a valve spool.
Quick Answer
Deburr only: a Tube End Deburring Cutter, 1/8″ to 2-1/4″ OD, ID and OD in one pass.
Weld bevel or fitting chamfer: a Tube End Chamfering Mill, 3/16″ to 2-1/2″ OD, 30° ID and 45° OD.
One side only: an Inside or Outside Chamfering Mill in 30° or 45° centerline.
Inside Chamfer, Outside Chamfer, or Both
The first decision is which edge needs cutting. Severance makes four families of tube end tools, all stocked in high speed steel; the Tube End Deburring Cutters are also stocked in carbide.
| Tool family | Cuts | Standard angles | Stock size range | Depth of cut | Best for |
|---|---|---|---|---|---|
| Tube End Deburring Cutters | ID and OD together | 30° C/L inside, 45° C/L outside | 1/8″ to 2-1/4″ tube OD | Light deburring only | Burr removal before fittings, flaring, or bending |
| Tube End Chamfering Mills | ID and OD together | 30° C/L inside, 45° C/L outside; specials available | 3/16″ to 2-1/2″ tube OD | Heavier chamfering | Weld bevels and fitting lead-ins with a machined finish |
| Inside Chamfering Mills | ID only | 30° or 45° C/L (60° or 90° included) | 1/4″ to 3″ head diameter | Fairly heavy chamfering | O-ring and seal lead-ins, hole and bore edges |
| Outside Chamfering Mills | OD only | 30° or 45° C/L (60° or 90° included) | 1/8″ to 3″ max cutting diameter | Heavy chamfer | Weld bevels on tube, pipe, and rod; one size covers many diameters |
The combination tools cut both edges in one stroke. The single-edge mills cut deeper and suit drawings that call out one chamfer while the other edge only needs the burr broken.
Chamfer Angles and Sizing by Tube OD and Wall
Reading the angle: centerline versus included
Severance tube tools are specified by centerline (C/L) angle, measured from the tube axis to the cutting edge. A 30° C/L cutter produces a 60° included angle, and 45° C/L produces 90° included. A weld procedure calling for a 30° bevel means C/L; a fitting drawing calling for a 90° chamfer usually means included, which is the 45° C/L tool.
The standard Tube End Chamfering Mill puts 30° C/L on the inside diameter and 45° C/L on the outside. Other angles can be ordered as specials.
Sizing by tube OD and wall thickness
Select by tube outside diameter first. Tube End Deburring Cutters are stocked from 1/8″ through 2-1/4″ OD in 19 sizes. Tube End Chamfering Mills are stocked from 3/16″ through 2-1/2″ OD in 23 sizes, each with a minimum and maximum wall. Thin-wall sizes start at 0.022″; the largest tools accept walls to 0.375″. The plug is the pilot that enters the bore and keeps the cutter concentric, so the tube ID must clear it. Tools T-36 and larger are furnished without shanks and take a threaded shank, ordered separately.
If your wall falls outside the range listed for your OD, an Inside Chamfering Mill sized to the ID or an Outside Chamfering Mill sized to the OD covers the job in two operations.
HSS Tube End Chamfering Mills - 30° I.D. / 45° O.D.
| Tubing O.D. | Wall Min. | Wall Max. | Plug Dia. | Shank Dia. | Tool Name | HSS EDP |
|---|---|---|---|---|---|---|
| 3/16″ | .022″ | .045″ | .152″ | 1/4″ | T-6 | 34960 |
| 1/4″ | .022″ | .065″ | .228″ | 1/4″ | T-8 | 34961 |
| 5/16″ | .022″ | .095″ | .290″ | 1/4″ | T-10 | 34962 |
| 3/8″ | .022″ | .095″ | .353″ | 3/8″ | T-12 | 34963 |
| 7/16″ | .028″ | .095″ | .409″ | 3/8″ | T-14 | 34964 |
| 1/2″ | .028″ | .095″ | .472″ | 3/8″ | T-16 | 34965 |
| 9/16″ | .028″ | .120″ | .534″ | 1/2″ | T-18 | 34966 |
| 5/8″ | .028″ | .120″ | .597″ | 1/2″ | T-20 | 34967 |
| 3/4″ | .028″ | .120″ | .722″ | 1/2″ | T-24 | 34968 |
| 7/8″ | .022″ | .156″ | .847″ | 1/2″ | T-28 | 34969 |
| 1″ | .035″ | .156″ | .965″ | 1/2″ | T-32 | 34970 |
| 1-1/8″ | .035″ | .187″ | 1.090″ | 1/2″-20 | T-36 | 34971 |
| 1-1/4″ | .035″ | .187″ | 1.215″ | 5/8″-18 | T-40 | 34972 |
| 1-5/16″ | .035″ | .187″ | 1.280″ | 5/8″-18 | T-42 | 34973 |
| 1-3/8″ | .035″ | .187″ | 1.340″ | 5/8″-18 | T-44 | 34974 |
| 1-1/2″ | .035″ | .250″ | 1.465″ | 3/4″-16 | T-48 | 34975 |
| 1-5/8″ | .035″ | .250″ | 1.590″ | 3/4″-16 | T-52 | 34976 |
| 1-3/4″ | .035″ | .250″ | 1.715″ | 3/4″-16 | T-56 | 34977 |
| 1-7/8″ | .035″ | .250″ | 1.840″ | 3/4″-16 | T-60 | 34978 |
| 2″ | .035″ | .312″ | 1.965″ | 1″-14 | T-64 | 34979 |
| 2-1/4″ | .058″ | .312″ | 2.195″ | 1″-14 | T-72 | 34980 |
| 2-3/8″ | .065″ | .375″ | 2.310″ | 1″-14 | T-76 | 34981 |
| 2-1/2″ | .065″ | .375″ | 2.435″ | 1″-14 | T-80 | 34982 |
Each EDP above links to the catalog on the Tube Chamfering Mills product page. Order by EDP through your distributor.
Running the Cutters in a Drill Press, Lathe or Dedicated Machine
Chamfering mills are chucking tools, most efficient in a lathe, screw machine, or drill press with the tube fixtured. The catalog states that holding parts by hand is not recommended and suggests V-block guides for quick positioning. For production, the deburring guide recommends a rigid fixture and an air cylinder or cam to control feed.
Tube End Chamfering Mills run at about 100 RPM for 1 inch steel tubing up to about 200 RPM for 1/2 inch tubing. Tube End Deburring Cutters run 50 to 200 RPM and Tube End Forming Cutters 50 to 350 RPM. Start slower on any new material or size and increase until results are best. For the RPM formula and material charts, see the speed and feed page.
HSS or carbide for stainless and hydraulic tubing
High speed steel is the right choice for mild steel, copper, aluminum, and brass tubing and for low-volume work. Carbide earns its cost on stainless, titanium, and other tough tubing, and on production runs where tool changes cost more than the tool. Tube End Deburring Cutters are stocked in carbide from 1/8″ through 1″ OD. The full trade-off is on the HSS vs carbide page.
Combination Deburr-and-Chamfer Tools, End Forming and Rod Ends
The Tube End Deburring Cutter deburrs and chamfers both edges of a tube end in one operation. The inside member cuts 30° C/L on the ID while the outside ring cuts 45° C/L on the OD, and the ring adjusts for more or less outside chamfer. These cutters are intended for light deburring; for a deeper weld bevel, step up to the Tube End Chamfering Mill.
When the tube end is exposed, or must be square with the tube axis, forming is the better finish. Tube End Forming Cutters machine the whole end into a smooth rounded lip on steel, copper, aluminum, and plastic tubing. Because they are solid, each cutter is made for one OD and one wall and is ordered by tool number plus wall (for example A-6-.035). They are not recommended for irregular wall or interrupted cuts.
Rod End Forming Cutters put a full radius on rod, wire, and pin ends from 1/32″ through 1″; specials can produce other radii or straight chamfers.
Step-by-Step Procedure and Common Mistakes
Procedure
- Measure the tube. Record OD, wall, and material, then confirm the wall is in range for the cutter and the plug clears the ID.
- Set the wall adjustment on a scrap piece and lock the socket screws.
- Fixture the tube in a V-block or collet, square to the spindle.
- Set speed. About 100 RPM for 1 inch steel, up to 200 RPM for 1/2 inch; slower on stainless and titanium.
- Apply cutting fluid to steel, stainless, and titanium; kerosene-based lubricant on aluminum.
- Feed in with light, even pressure. A clean curling chip is right; a powdery or blue chip means too much heat, so slow down or add oil.
- Inspect the first part with a 10x loupe, adjust the ring if needed, then run.
- Clean the flutes with a brass brush and store the cutter so its edges touch nothing.
Common Mistakes
- Over-chamfering thin wall. A chamfer that consumes a 0.022″ wall leaves a knife edge that will not weld or seal.
- Wrong pilot. A plug that does not fit the bore lets the cutter wander off center.
- Speed too high. Drill speeds burn the edge, work-harden stainless, and cause chatter.
- Dwelling on stainless. Rubbing without cutting work-hardens the surface. Feed in, cut, and pull out.
- Running a dull cutter. A dull tool rolls the burr over instead of shearing it. Send worn mills to the regrind service.
Frequently Asked Questions
Severance Tube End Chamfering Mills produce 30° centerline on the ID and 45° on the OD as standard. Separate inside and outside mills come in 30° or 45° centerline (60° or 90° included). Other angles are available as specials.
Yes. Every Tube End Chamfering Mill adjusts for wall thickness within the range listed for its tube OD. Tube End Forming Cutters are solid, so each one fits a specific OD and wall.
About 100 RPM for 1 inch steel tubing up to about 200 RPM for 1/2 inch tubing. Combination Tube End Deburring Cutters run 50 to 200 RPM. Start slow and increase until the tool cuts cleanly.
HSS handles most steel, copper, aluminum, and brass tubing. Carbide is the better choice for stainless, titanium, and production runs. Tube End Deburring Cutters are stocked in carbide from 1/8 inch through 1 inch OD.
Outside Chamfering Mills may be used in a portable power tool where requirements are not exacting. For a weld bevel or fitting-quality chamfer, chuck the cutter in a drill press or lathe and fixture the tube. Holding parts by hand is not recommended.
Yes. Chamfering mills can be reground many times. Severance offers a regrind service with a 1-3 week turnaround that restores the original geometry.