How to Chamfer a Pipe (Inside/Back Side) with Erix Tool 

To chamfer the inside edge of a pipe or tube quickly and consistently, use an Erix back-chamfering tool: a spindle and folding “wing” cutter that passes through the bore, opens behind the wall, and then machines the chamfer on the way back. This gives you a clean, controlled angle (30°, 45°, or 60°) without flipping the part.  

How the tool works 

• The Erix tool has one moving part (the wing). It folds into the spindle recess to enter the bore and swings out by rotation once it has passed the wall thickness. The pilot on the spindle guides in the bore; spindles ≥ .394″ have coolant-through for chip control.  

Choose the chamfer angle and size 

• Standard back-chamfer angles: 45°, 60°, 30° (series prefixes 45–, 60–, 30–). If you need something else, Erix supplies semistandard/special angles down to 15°.  

• Select a spindle by the pipe’s bore (hole) diameter and a 34– series wing for the required angle. Back-chamfer listings cover .188–2.688 in bore sizes with the matching spindle/wing combinations.  

Set speed and feed correctly 

1. From the material table, find the Number/Letter code for your workpiece material and wing type (HSS or carbide). 

2. Using that code and the chamfering diameter (not the hole diameter), read recommended feed (in/rev) and spindle speed (RPM) from the tables. 
   These are the official steps for both spotfacing and chamfering.  

Run procedure (manual or CNC) 

1. Prepare 

• Verify the wing swings freely; back off the pivot screw ~30° before locking. Fit the correct insert (K20 for cast iron, P40 for steel). Secure the holder rigidly. Use thin oil in the bore; use coolant for steels.  

2. Enter the pipe bore 

• Start counter-clockwise (viewed from the machine toward the headstock). Rapid feed to the bore, then reduce to ≤ .008 in/rev so the wing closes by contacting the bore and passes through.  

3. Open the wing 

• Advance until the entire wing is clear behind the pipe wall so it can swing out. (On large tools with a guide tang, ensure the tang is clear, too.)  

4. Cut the chamfer 

• Reverse to clockwise rotation and apply feed and speed from the table for the chosen chamfer diameter. Machine until the programmed chamfer depth/width is achieved.  

5. Retract and exit 

• Rapid retract to clear the wing, switch back to counter-clockwise, and re-enter at ≤ .008 in/rev so the wing fully closes before withdrawing through the bore.  

Tips for best results on pipe 

• Coolant-through breaks and evacuates chips and keeps the wing cool—use it whenever possible.  

• For interrupted cuts (e.g., across a weld seam or heavy fillet), increase speed up to 2× and reduce feed 20–30% on small spindles (≤ 1.181″).  

• If you fight built-up edge or tough alloys, consider P40 grade inserts for steel, K20 for cast iron, add chipbreakers, or reduce the positive chipping angle as recommended.  

Part numbering at a glance 

• Spindle (27–) + bore + shank (e.g., 27–25.4–CS19.1). 

• Back-chamfer wing (34–) + angle (30/45/60) and insert size (e.g., 34-121-60).  

Conclusion

Chamfering a pipe’s internal edge is fastest and most consistent with an Erix back-chamfering setup: pick the angle, size the spindle to your bore, set speed/feed from the table, and follow the open-cut-close sequence above. If you share your pipe ID, wall thickness, material, and desired chamfer angle/width, Erix Tool will propose the exact 27– spindle and 34– wing (with insert grade) plus starting parameters for your machine. Contact Erix Tool to get a precise recommendation for your application.