VOLUME

How to make a climbing volume (DIY plywood guide)

A climbing volume is a three-dimensional plywood shape you screw onto a climbing wall to change the terrain. Holds bolt onto its faces; the volume itself becomes part of the route. This guide walks you through designing, cutting, assembling, and mounting a wooden volume yourself — including how to get accurate dimensions without CAD software.

What you need

  • Structural plywood — typically 18 mm (≈¾″) Baltic birch or equivalent ACX-grade sheet (see materials guide)
  • Wood glue, clamps, and screws with pilot holes
  • Circular saw, jigsaw, or table saw; sandpaper
  • Drill, Forstner/spade bit for T-nuts, countersink
  • T-nuts and mounting screws sized for your wall
  • Plans: edge lengths, mitre/bevel angles, hole layouts

You can derive those plans by hand, in CAD, or in the free VOLUME browser designer — sketch sides and slopes, then export a print pattern, cut list, or CNC files.

Step 1 — Design the shape and get dimensions

Decide the footprint (triangle, rectangle, wedge, hex, custom N-gon), wall thickness, overall height, and face slopes. Steeper faces climb differently; small home-wall volumes often sit in the 100–250 mm height range with side lengths from roughly 200–600 mm.

In VOLUME you:

  1. Open the designer (no CAD degree required).
  2. Set units (mm or inches), scale, wall thickness, global slope and height.
  3. Edit each side length and angle while watching the live 3D model.
  4. Optionally enable T-nut grids and mounting-screw layouts.
  5. Order the exports you need — start with a print pattern and cut list for hand building, or DXF/STEP for CNC (see hand-cut vs CNC).

More detail: design without CAD and dimensions & cut lists.

Step 2 — Transfer the pattern to plywood

Print the dimensioned face schematics (A4/Letter tiles if needed) or mark edges from the cut list. Transfer outlines to the face of the plywood, including mitre notes at each edge. Double-check that top edges are shorter than bottom edges for frustum-style volumes so panels close correctly.

Step 3 — Cut panels and join edges

Cut each panel carefully. Mitre or bevel angles matter: wrong angles leave gaps or force the shell out of square. Dry-fit all faces before glue. Assemble with wood glue and screws into pilot holes — never drive into thin plywood edges without pilots, or you risk splitting the laminate.

Sand edges smooth enough for skin and holds. Paint or texture after hardware holes are planned so you do not clog T-nut seats.

Step 4 — T-nuts and mounting holes

Drill T-nut holes from the climbing face, install T-nuts from the back, and keep a consistent grid or staggered pattern for setting flexibility. Add mounting screw holes through the back/base so the volume can be fixed into wall framing or plywood. Defaults and spacing ideas: T-nut spacing on climbing volumes.

Step 5 — Mount on the wall

Position the volume where framing can take the load — not only into thin panel skin. Use sufficiently long wood screws through the volume’s mounting holes into studs or backing. Recheck that holds clear the wall and that steep faces still leave room for climbers’ bodies.

Hand tools vs CNC

Home builders often succeed with print patterns and careful measuring. Gyms and shops usually prefer nested DXF/STEP for repeatable CNC cuts. Pick the path (and files) that match your tools: hand-cut vs CNC climbing volumes.

Stackable and multi-level volumes

Some designs nest a smaller volume on top of a larger base for dramatic features. That needs matching inset seating and careful nest layout on the sheet — covered in stackable climbing volumes.

FAQ

What plywood thickness should I use?

For bolt-on holds and T-nuts, 18 mm / about ¾″ structural plywood is the usual minimum. Thinner sheet flexes and T-nuts pull through more easily.

Can I make a climbing volume without CNC?

Yes. Dimensioned print patterns and a cut list are enough for circular saw or jigsaw work if you cut and mitre carefully.

How do I get accurate dimensions without CAD?

Use an online volume designer such as VOLUME: set sides, slopes, and height, then export plans. That replaces manual trigonometry for most frustum shapes.

Wooden volume vs fiberglass?

Plywood volumes are planar faces, repairable, and DIY-friendly. Fiberglass suits organic shapes and often commercial production. Most home and many gym features start as plywood.

Next step: Create your volume free in the browser — then export the plans that match how you cut.