Create accurate flat patterns
for pipes, cones, transitions and branches
Preview your part in 3D and export production-ready DXF files for plasma, laser and oxy-fuel cutting.
How sheet metal development works here
Choose a part
We develop new parts constantly!
Enter measurements
All measurements are in millimetres.
See and place dimensions on your results
You can also export to CAD or print to PDF
Flat patterns for pipe fabrication
Each part has a page covering what it is, which measurements the calculation needs and a worked example — from cones and transitions to branches and segmented bends.
- Cylinder
- Cone
- Oblique Cone
- Offset Cone
- Chinese Hat
- Truncated Cylinder
- Double Cut Cylinder
- Bend
- 90° Bend
- 180° Bend
- Elbow
- Portico
- Elliptical Tube
- Oval Tube
- Helicoid
- Rectangle to Round
- Inclined Square to Round
- Pipe Branch (Tee)
- Rectangular Transition
- Eccentric Rectangle to Round
- Discharge Chute
- Angle Cut Cone
- Cylinder with Branch Hole
- Rectangular Duct Bend
- Breeches Trunk (Fish Mouth)
- Cross Shell
- Spherical Head in Gores
- Round to Oval
- Truncated Rectangular Tube
- Cone Branch
- Cone with Branch Hole
- Offset Pipe Branch (Tangential Inlet)
- Rectangular Tap on Pipe
- Cylinder with Rectangular Hole
- Conical Tap (Conical Tee)
- Tapered Segmented Bend
- Cylinder with Conical Branch Hole
- Angular Boot, Rectangle to Round
- Parallel-Axis Nozzle on a Cone
- Cone with Parallel-Axis Nozzle Hole
- Obround to Rectangle
- Regular Pyramid Frustum
- Rectangular Tap on a Cone
- Cone with Rectangular Hole
- Nozzle on a Spherical Head
- Conical Tap on Cone
- Cone with Conical Tap Hole
- Oval Segmented Bend
- Oval to Oval Reducer
- Tapered Breeches
Frequently asked questions
Is Planichapa free?
Yes, within a limit: 20 calculations a month, with the drawing, the 3D view and PDF export, and no ads. DXF export, unlimited calculations and saved history are part of full access.
Do I need an account to see the parts?
No. The part list and the page for each part are open. The account is only asked for when you calculate, because the calculation is what gets saved to your history.
Does sheet thickness affect the result?
It does. Every development is calculated on the neutral axis, at mid-thickness, where the sheet neither stretches nor compresses as it is formed. That is why a can's blank length is π times the mean diameter, not the outside one.
Can I take the drawing to a cutting table?
Yes. DXF export writes the outline as lines and arcs, which is what plasma, laser and oxy-fuel tables read. DXF is part of full access.
What units do I enter?
Millimetres. Results come back in the same unit.