Until you have the skills to build spoked wheels, make solid disc wheels from three planks edge-joined and cut round; they are heavy but serve well for low-speed hauling. A bigger wheel climbs obstacles more easily: to roll over a 5 cm step, a 50 cm disc needs a pull of 75% of its load, a 60 cm disc 66%, and a 120 cm spoked wheel 44%.
Part of Cart & Wagon Construction
Basic wheels are solid wooden discs, usually three planks edge-joined and cut to a circle, used on carts until spoked wheels can be built.
Why Start With A Disc
A solid disc needs no steam bending, no lathe and no complex joinery: planks, dowels, a saw and an axe will do. It is heavy and has no give, so it suits slow work on rough ground. The parent article places solid wheels as the stage before wheelwright skills, and Solid Wheels and Spoked Wheels cover both kinds in full. The way a plank disc is made is in Solid Disc Wheels.
Why Diameter Matters: Climbing A Step
A wheel meeting a step of height h must be lifted over it by a pull at the axle. Taking moments about the step’s edge, with the wheel’s radius r and weight W on the wheel, the horizontal pull F at the axle that just lifts it is
F / W = √(2rh - h²) / (r - h)
For a step h = 0.05 m high:
| Wheel diameter | Radius r | F / W | Pull for 250 kg on the wheel (W = 2,453 N) |
|---|---|---|---|
| 50 cm | 0.25 m | √(0.025 - 0.0025) / 0.20 = 0.15 / 0.20 = 0.75 | 1,840 N |
| 60 cm | 0.30 m | √(0.030 - 0.0025) / 0.25 = 0.166 / 0.25 = 0.66 | 1,630 N |
| 70 cm | 0.35 m | √(0.035 - 0.0025) / 0.30 = 0.180 / 0.30 = 0.60 | 1,470 N |
| 120 cm | 0.60 m | √(0.060 - 0.0025) / 0.55 = 0.240 / 0.55 = 0.44 | 1,070 N |
This is statics: the pull needed to lift a wheel from rest over a sharp edge, with no allowance for momentum, softening of the ground or a rounded edge, so real pulls are lower. As percentages of the load on the wheel, the four pulls are 75%, 66%, 60% and 44%. It shows the trend: a wheel 2.4 times the diameter needs 0.44 / 0.75 = 59% of the pull. The parent’s disc, with a radius of 25-35 cm, sits at the bad end of that range.
What You Need
- Three planks of hard, dense wood, 4-5 cm thick (Solid Disc Wheels)
- Hardwood dowels and glue or wet rawhide
- A saw or axe, and a drill, to cut the circle and bore the hub
- An axle arm to size the hub hole against (Wooden Axle Construction)
Method: In Outline
- Edge-join three planks into a panel.
- Scribe a circle of 25-35 cm radius and cut it round.
- Bore the centre hole to the axle arm: too loose and the wheel wobbles; too tight and it seizes.
- Smooth the bearing hole and add reinforcement: cross-battens, an iron band or a rawhide rim.
Common Mistakes
- A hole that does not match the axle — see the sizing rule in step 3.
- Unseasoned planks — they split and loosen as they dry.
- No rim protection — the bare edge wears quickly; the parent article lists iron bands and wet rawhide as options.
- Staying with disc wheels for long distances — a bigger, lighter spoked wheel rolls over obstructions more easily.
Safety
Heavy discs and cutting tools
A solid wheel of dense wood is heavy and rolls: it can fall from a bench onto feet, and a loose wheel on a loaded cart can run a long way downhill. Chock a cart on any slope, never stand downhill of a loaded cart, and clamp planks when sawing or axing the circle.
What’s Next
- Learn next: Solid Disc Wheels — making one
- Combine with: Wheelwright Craft — the spoked wheel that replaces it