Tube Bending Fan Calculator
All tubes in a fan share the same run. Choose your fan type, enter tube count, spacing, and run to get kick angles, travels, and rises for every tube in the rack — no limit on tube count.
All tubes kick the same direction — use when the whole rack changes planes.
How a Tubing Fan Works
A tubing fan is a set of tubes in a rack that all need to kick from one plane to another. Every tube shares the same run — the same horizontal distance from where the kick starts to where it ends. What changes per tube is the rise it needs to cover, which drives the kick angle and travel for that tube.
Mark all your tubes at the run distance from the reference end. Then bend each one at its calculated angle. The tubes will all land on the same plane at the end of the run.
One Direction vs. Symmetric
One Direction — all tubes kick the same way (all up or all down). Use this when the entire rack needs to change planes — for example, tubes running vertically that all need to go horizontal, or a horizontal rack dropping to a lower elevation. Tube 1 has the minimum rise (can be zero if that tube is already at the target). Each tube out from there adds one spacing increment of rise.
Symmetric — the target plane runs through the center of the stack. The center tube (or innermost pair for even counts) has the least rise, and tubes fan out equally above and below. Used when the rack splits to both sides of a centerline.
Formulas Used
Symmetric Pairs
In Symmetric mode, tubes equidistant from center are mirror images. They have the same rise magnitude, kick angle, and travel — one bends one way, the other bends the opposite by the same amount. The collapse-pairs toggle cuts the table in half so you only see the unique calculations.
Odd vs. Even Tube Counts (Symmetric mode)
For an odd count there is a single center tube with zero rise — no kick needed. For an even count the two innermost tubes each have a rise of half the center-to-center spacing in opposite directions.
| Tubes | Center / Inner pair | Unique calculations |
|---|---|---|
| 5 | Tube 3 — zero rise | 3 (center + 2 pairs) |
| 6 | Tubes 3 & 4 — ½ spacing rise | 3 pairs |
| 7 | Tube 4 — zero rise | 4 (center + 3 pairs) |
| 100 | Tubes 50 & 51 — ½ spacing rise | 50 pairs |
Frequently Asked Questions
What is a tube bending fan?
A tubing fan is a group of tubes in a rack that all share the same run but each make a different kick to reach a common plane. The run is fixed for every tube. What changes is the rise each tube must cover based on its position in the stack, which determines the kick angle and travel.
What is the difference between One Direction and Symmetric?
In a One Direction fan all tubes kick the same way — useful when the entire rack needs to change planes together, like going from a vertical run to a horizontal plane. In a Symmetric fan the target plane runs through the center of the stack, so tubes fan out equally above and below center with the middle tube needing the least (or no) kick.
Why do all tubes in a fan have the same run?
The run is the straight-line horizontal distance from the start of the kick to the end. Every tube kicks from the same reference point to the same landing point, so the run never changes. That is why you mark all tubes at the same distance from the end — only the bend angle and travel differ.
What does travel mean in a tubing fan?
Travel is the actual length of tube used by the kicked section — the hypotenuse of the right triangle formed by rise and run. Travel = √(rise² + run²). Tubes with more rise always have more travel, even though all runs are equal.
How do symmetric pairs work?
Tubes equidistant from center have identical rise magnitudes and therefore identical kick angles and travels. One bends one direction, the other bends the opposite by the same amount. Use the collapse-pairs toggle to see just the unique numbers — for a 100-tube symmetric rack that cuts the table from 100 rows to 50.
Does this calculator account for bender deductions?
No — this is pure geometry. It gives you rise, angle, and travel from run and spacing. Bender deductions depend on your specific bender, tube OD, and bend radius. Mark all tubes at the run distance, then apply your bender's normal deduct for that angle as you would any other kick.