A folded paper arch sculpture

PLAN BEFORE YOU COMMIT

Fit, dimensions & layout

Draw the 180 × 160 mm front as an outer arch and a smaller inner opening with broad legs. The example depth is 50 mm. Make a complete scrap-card shell first: the two front faces need outer and inner connecting strips, each with glue tabs beyond the 50 mm visible depth. A paper template around the curves gives strip lengths more reliably than guessing.

Starting size180 × 160 × 50 mm

Active work90 minutesAllow additional product-specific drying or curing time.

The illustration is a concept, not a scale drawing or a record of a tested build. Use a full-size template or dry fit to check the written layout with your actual materials.

Choose materials deliberately

Open-backed version

Use one front face with folded feet as a separate simpler prototype. It has different balance and should not be presented as the same closed shell.

Thicker board

It needs a different cutting and scoring approach. Avoid forcing heavy board into a tight curve; enlarge the curve or return to lighter cardstock.

Make it, step by step

Prototype the shape
Draw a broad upside-down U with wide legs and test in scrap paper.
Step 1 complete
Cut matching faces
Use one face to trace the other, keeping the lower ends level.
Step 2 complete
Prepare depth strips
Make strips with 50 mm of visible depth plus glue tabs along both sides. Prepare an outer strip and an inner-opening strip using the paper prototype for lengths. Segment the tabs around curves.
Check before moving on
Add glue tabs outside the 50 mm depth, then snip the tabs into short segments so they can turn around the curve.
Step 3 complete
Join the shell
Connect the faces along the outside and the inner arch opening using the fitted depth strips. Keep their visible depth equal and align the two feet on a flat surface as the joints set.
Check before moving on
Join the inner opening as well as the exterior to connect both faces into a continuous shell.
Step 4 complete
Dry and balance
Keep both feet aligned while the glue dries and display away from drafts.
Step 5 complete

IF SOMETHING DOES NOT FIT

Troubleshoot this project

Why does the arch twist?

What to check. Connecting strips may differ in depth or one face may be offset.

Next move. Check strip widths and align both feet while the glue can still be positioned.

Why are the inner edges unfinished?

What to check. The shell needs an inner depth strip as well as an outer one.

Next move. Fit the inner strip in the prototype, allowing segmented tabs to follow its curve, before starting the final card.

The final check

Both feet sit level and the shell does not twist.

A detail worth keeping

A shallow broad curve is easier to join than a tall narrow arch.

FROM THE FIELD NOTES

Close both boundaries of a shell

A hollow paper arch has two faces, an outside depth strip, and an inside depth strip around the opening. All visible depth strips share the same width, with tabs added outside that width. Build the whole shell in scrap before moving to your best card.

Read the Craft Buildr notebook ↗

Record your actual sizes, material changes, and the result of your fit check in your project notebook. Keep the product name with any finish or adhesive sample.

Use a stable work surface and tools within your experience. Follow the exact tool and product instructions for preparation, dust control, ventilation, and cure. These decorative concepts have no structural load rating. Stop if the material or existing finish cannot be identified.

A folded paper arch sculpture

Fit, dimensions & layout

Gather your materials

Tools to have nearby