U-Bend Tube Marking Tool – Pipe Angle Finder & Degree Marker

Mark perfect cuts on mandrel U-bends, every time.

Cutting a mandrel bend exactly at the tangent, or at a precise angle, is one of the trickiest parts of fabricating exhaust, intake, and intercooler piping. Eyeballing it gets you gaps, bad fit-up, and wasted tubing. This tool sits on your U-bend and gives you an accurate degree line to cut to, and doubles as an angle finder for matching an existing cut.

What it does

• Marks the tangent of any U-bend so your straight sections line up perfectly.
• Marks any angle in degrees along the bend for cuts like 30°, 45°, and 60°.
• Finds the angle of a cut tube, so you can measure an existing piece and replicate it exactly.
• Custom-fit to your exact tube OD and centerline radius, so it seats on the bend without rocking.

Includes

• 1x radius bottom block, sized to your tube and CLR
• 1x swivel arm with degree markings

Specs

• Fits: any tube OD and centerline radius you specify
• Lead time: made to order, ships in 2 weeks or less
• Colors may vary unless specified

How to use it

1. Set the radius block on the U-bend so it seats against the outer radius.
2. Swing the arm to your target angle and mark along its edge.
3. Cut to your line, or set the tool on a cut tube to read its angle.

Pairs well with our weld elbow saw jig and X-pipe exhaust cutting jig to mark and cut bends on a bandsaw. 

FAQ

Q: How do I find my centerline radius?
A: It’s usually printed on the bend’s spec sheet or listing, often as a multiple of the tube OD (for example, 1.5D CLR on a 3" tube is a 4.5" radius). You can also measure from the center of the bend to the centerline of the tube.

Q: Will one tool work for multiple tube sizes?
A: No. Each tool is matched to one OD and CLR for accuracy.

Q: Does it work on stainless, aluminum, and mild steel?
A: Yes. It marks the tube’s surface, so the material doesn’t matter.