Quick answer: To use a tube notching template, identify the intersection angle, choose the template that matches your tubing’s outside diameter, align the template with the tube, trace the cut profile, remove the material, and fine-tune the notch until the joint fits properly.
A tube cope cut, sometimes called a fishmouth or tube notch, allows one piece of tubing to fit against another. Getting that profile right is an important part of building roll cages, exhaust systems, chassis braces, railings, headers, and other tube-fabrication projects.
This guide explains how to use a tube notching template to create cleaner, more repeatable layout marks before making the first cut.
Why Accurate Tube Cope Cuts Matter
If you have ever tried to fit tubing freehand, you know how quickly the process can turn into repeated cutting, grinding, and test-fitting. A poorly fitted cope can create large gaps, require more filler, increase cleanup time, and make the joint harder to weld consistently.
A tube notching template addresses the problem during layout. It gives you a clear profile to follow before removing material, helping reduce guesswork and unnecessary grinding.
What You’ll Need
- Tube notching template matched to your angle and tube outside diameter
- Fine-tip marker or metal scribe
- Angle grinder, bandsaw, or plasma cutter
- Flap disc, deburring tool, or die grinder
- Tape measure, calipers, angle finder, or protractor
- A secure vise or suitable workholding method
- Safety equipment required for your cutting and welding process
Safety reminder: Inspect your tools and cutting wheels before use, keep guards installed, secure the tubing, remove nearby combustible materials, provide appropriate ventilation, and wear the correct eye, face, hearing, hand, and body protection.
Step 1: Identify the Tube Intersection Angle
First, determine the angle at which the tube being notched will meet the receiving tube. Using the wrong angle template is one of the easiest ways to create an incorrect profile.
- 90°: Perpendicular T-joints, roll-cage tubes, chassis braces, exhaust balance tubes, and handrails
- 45°: Diagonal braces, A-pillar bars, door bars, exhaust tubing, and angled railings
- 30° and 60°: Header primaries, lower chassis rails, angled strut bars, Y-pipes, and other tight-angle connections
If you are unsure of the angle, mock up the tubes and measure the intersection with a digital angle finder or protractor before cutting.
Step 2: Match the Template to the Tube Outside Diameter
Tube notching templates are sized according to the outside diameter, or OD, of the tube being notched. If you are working with 2-inch OD tubing, use the 2-inch template for the required angle.
Do not assume a nearby metric size is identical. For example, 45 mm tubing is not exactly the same as 1.75-inch tubing. Using an incorrectly sized template may require additional hand fitting.
Step 3: Wrap and Align the Template
Place the template around the end of the tube being notched. The template should sit securely against the tube without being twisted or rotated.
Use these alignment checks before marking:
- Align the template’s centerline with the top-dead-center mark on the tube.
- Make sure the template sits square to the tube end.
- Confirm that the template has not rotated around the tube.
- Hold the template firmly or secure it temporarily while marking.
To mark the end of the tube being notched, trace the outside profile of the template. If the joint requires a flow opening in the receiving tube, place the template on that tube and trace the appropriate inside opening.
Take your time during alignment. A small positioning error can create an uneven cope and add unnecessary grinding later.
Step 4: Mark the Cope Cut Line
Use a sharp scribe or fine-tip marker to trace the complete profile onto the tubing. Apply consistent pressure and keep the marker against the template edge throughout the pass.
After removing the template, inspect the line from every side. It should be continuous, easy to see, and symmetrical around the tube.
Step 5: Cut the Tube Notch
The best cutting method depends on the tools available and the shape of the notch.
- Angle grinder and cutoff wheel: Leave the marked line visible and remove the remaining material gradually with a flap disc. This method works well for one-off fabrication projects.
- Bandsaw: Make controlled cuts near the layout line, then finish the profile with a grinder or deburring tool.
- Plasma cutter: Follow the marked profile while leaving enough material for final cleanup. Remove slag and inspect the cut before test-fitting.
Do not try to reach the final profile in one aggressive cut. Leave a small amount of material outside the line and gradually work toward the finished shape.
Depending on the tubing’s wall thickness, flat or squared areas may remain inside the notch. Carefully round these contact points until the tube seats properly against the receiving tube.
Important fabrication tip: Leave the tube longer than its finished measurement while creating the notch. Complete the cope and achieve the proper fit first, then trim the opposite end to final length.
For example, if you need a 60-degree notched tube to finish at exactly 6 inches, cutting the tube to 6 inches before fitting could leave it short after material is removed during final adjustment.
Leave it long. Create the fit. Cut to final length.
Step 6: Test-Fit and Fine-Tune the Cope
Place the notched tube against the receiving tube and check the joint from multiple angles. A properly fitted cope should sit securely with minimal rocking and a consistent fit around the perimeter.
If the tube contacts on one side or does not seat fully, mark the contact point and remove a small amount of material with a flap disc or die grinder. Repeat the process using small, controlled passes.
Do not force the tubes together. If the notch will not seat over the receiving tube, additional material needs to be removed from the contact points.
Step 7: Tack and Weld the Joint
Once you are satisfied with the fit and alignment, tack the joint before completing the weld. Multiple evenly spaced tack welds can help hold the tubes in position as heat is introduced.
Recheck the tube’s position after tacking. Welding requirements vary based on the tubing material, wall thickness, joint design, application, and applicable fabrication standards.
Common Tube-Notching Mistakes
- Using the wrong angle: Verify the intersection angle before choosing a template.
- Selecting the wrong tube size: Match the template to the tubing’s actual outside diameter.
- Rotating the template: Keep the centerline correctly aligned throughout marking.
- Cutting directly through the line: Leave material for final adjustment.
- Skipping the test fit: Always check the complete joint before welding.
- Cutting to final length too early: Complete and fit the notch before trimming the tube to its finished length.
- Forcing the joint together: Identify the contact points and remove material gradually.
Tube Notching Template FAQs
What size tube notching template should I use?
Choose the template that matches the outside diameter of the tube being notched. A 2-inch OD tube requires a 2-inch template.
Can I use a tube notching template with an angle grinder?
Yes. Trace the profile, cut while leaving the line visible, and gradually bring the notch to its finished shape with a flap disc or similar finishing tool.
Should I cut tubing to final length before notching it?
No. Leave extra length while creating and fitting the cope. Once the joint fits correctly, measure and cut the tube to its final length.
Do tube notching templates make the cut?
No. The template creates the layout profile. You still make and finish the cut using the appropriate fabrication tools.
What projects can tube notching templates be used for?
Common applications include roll cages, chassis braces, headers, exhaust systems, handrails, structural tubing, and general custom fabrication.
Find the Right Tube Notching Template
Keystone Met’L Co. offers tube notching templates in 30°, 45°, 60°, and 90° configurations, including seven common tubing sizes from 1.5 inches through 3 inches in 0.25-inch increments.
You can choose an individual angle kit or get all four angles and all seven sizes in the 28-piece Tube Notching Template Bundle.
Shop all Keystone Met’L Co. tube notching templates.
Working on a fabrication project? Tag @KeystoneMetL on social media or send us your project photos. We would love to see what you are building.