Zip-top round bag — trial patterns and 3D configurator

Zip-top round bag: adjustable dimensions, separate pieces, holes and PDF, SVG, DXF export. Trial construction for checking on a mock-up.

Trial diameter 200 mm, depth 65 mm. Two discs, lower side strip, upper strip with a slot for the zipper, fasteners and strap. The strip lengths are recalculated along the arcs; different width and height produce an oval.

Open this example in the designer

The example opens with the dimensions specified below. Its changes are saved separately from your regular work. You can return to it using the link in the editor.

Example source parameters

Linear dimensions are given in millimeters. Parameter names match the designer fields; these are the initial settings and can be changed.

Parameter	Value
Body width	200
Body height	200
Body depth	65
Strap blank	1100
Strap width	20
Leather thickness	1.5
Stitch offset from edge	4
Additional seam allowance	0

Parts in this example

The dimensions below are derived from the geometric model. The parts list changes with the parameters and enabled options.

Piece	Size, mm
Front disc	200.0 × 200.0
Back disc	200.0 × 200.0
Upper side panel with zipper	314.1 × 65.0
Lower side panel	314.1 × 65.0
Strap attachment · 1	20.0 × 60.0
Strap attachment · 2	20.0 × 60.0
Adjustable strap	1100.0 × 20.0

How the size changes the pattern piece

Calculation example: the “body width” parameter was changed from 200 to 220 mm. The diagram shows the “Front disc” piece before and after recalculation at the same scale.

Zip-top round bag: Body width 200 and 220 mm — The dimensions below the drawing refer to the outer cut-edge contour. This is the result of a geometric calculation.

Open modified example

You can also download the modified JSON project. After modification, check the assembly on a mockup.

Download the pattern example

The files were generated using the standard VLOTHO CAD export from the parameters specified above. They show the model geometry and do not replace checking the product in the material.

PDF A4, 15 sheets PDF patterns, 1:1 SVG patterns, 1:1 DXF patterns, mm JSON project

PDF A4 automatically selects portrait or landscape pages and rotates the pieces to reduce the number of sheets. For assembly, a 10 mm overlap, numbers, and alignment marks are provided. The standard PDF contains one piece per page. Both variants include a 100 mm test segment. For your own dimensions, modify the project and export a new PDF. How to print patterns at 1:1 scale.

What to check before cutting

Calculated construction. Physical sewing has not been tested. First assemble a paper or inexpensive leather mock-up, then refine the fit and hardware.

VLOTHO CAD builds a geometric prototype. Allowances for bending, skiving, assembly thickness, and construction methods are determined by your material. Start with a paper mockup and a trial piece.

How to get a pattern for your dimensions

Open the model and set the dimensions in millimeters. To reproduce the tabular example, first load its JSON.
Check the parts list and enabled options. Adjust the seam and dimensions for your material.
Save the project and export a new pattern set. After changing the dimensions, the previous files no longer correspond to the project.

Dimension reference for this model: Stitching line. Dimensions in the parts table and the outer cut contour may differ due to the seam allowance. How to check seam allowances and stitching lines.

Materials and assembly

Select the leather according to the required stiffness and assembly method. The image was generated and shows the intended appearance.

File preparation

Printing patterns on A4 at 1:1 scale · DXF units and layers before cutting

Next step

Construction and export instructions · Manual contour editing · All models