WHEELWRIGHTTHE BACK BENCH

LATERAL RUNOUT——

RADIAL, LOADED——

DISH UNDER LOAD——

HUM ON THE ROAD——

LACECART WHEEL, 700 mm3 ROLLS LEFT

The jig has left every spoke somewhere near the mark. None of them agree.

SPOKE 1NEAR FLANGE

SET— PULL— ON THE ROAD— CROSS—

Take the felloe down until it runs round. Every millimetre you take stiffens it less.

1.0 mm

A pad at 70-odd. The wagon is heavy but the felloe is sound.

74 psi

Load it, lift the cart, and run it down the lane. Listen to what comes back.

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ready to lift

WHEELWRIGHT

Every spoke
must agree

A wheel is held in shape by its spokes, and a wheel is only true when every one of them is pulled to the same tension. Too much on one side and the wheel dishes; too little and it runs out; a spoke crossed wrongly fights its neighbours. Build it, true it, fit a tyre — then lift the cart and roll it, and hear the disagreement.

←→ choose a spoke · WS pull it tighter or slacken · X cross · Z lead or trail · Space go on · M sound · H help

ON THE BENCH

THREE ORDERS a barrow wheel, a dished wagon wheel, and a mill wheel that wants mending.

THREE ROLLS EACH a wheel goes on the road or it does not go at all.

ONE TRUTH the wobble you see and the noise you hear are the tension you set.

PAUSED

The wheel is where you left it.

WHAT THE NUMBERS MEAN

Runout, dish, and the noise between them

Set / pull
A spoke you pull to 1250 lbf does not hold 1250. It holds whatever is left after its own slack is taken up. The pull is the number that matters, and no two spokes have the same slack.
Lateral runout
How far the felloe wanders from side to side as the wheel turns. It comes from neighbours disagreeing: too much on one flange and too little on the other, and the section between them is dragged across.
Radial runout
How far the felloe wanders in and out of true. It comes from a spoke pulling its own section in, a bend in the wood, and the tyre squashing the whole rim under the load.
Dish under load
How far the wheel hangs to one side. A disagreement that hits every spoke on one flange the same way dishes the wheel instead of warping it — and the wheel thumps once a turn rather than humming.
Hum
The order the wobble repeats at, times the turns of the wheel per second. It is not a lookup: the sound is the runout, and the pitch is its shape.
Crossing
Crossing braces the felloe against sideways movement, so the same disagreement makes less wobble. Crossing unevenly is worse than not crossing at all.
On the road
A tyre under pressure squeezes the felloe and raises the running tension. A wheel safe on the bench can still let a spoke go at speed.

OFF THE ROLL

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    THE DAY'S WORK

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