Pump Derby

A 4-lane tabletop horse race. Every full pull of your ring moves your horse one notch, and the first flag up wins.

Four horses on the start line, one lane each. Every player sits behind a pump house with a ring on the table in front of them.

Pull the ring about 2 in. Its cord turns a weighted drum inside the pump house, and the drum's arm drives a toothed slider along the lane.

The slider pushes the sled exactly one notch, 10 mm. The horse rocks on its hind hoof and nods 5.3° as it goes.

Let go. Four steel nuts swing the drum home in about 0.12 s, and the orange pawl drops behind the next tooth with a clack.

Everyone pulls at once. Above 4.3–4.6 pulls a second the drum is not home yet, so the pull gains nothing. Rhythm wins.

On notch 19 the number paddle lifts the flag past its balance point, and it swings upright.

To race again: lift the orange grip, slide it aside, push the horse home, slide it back and tip the flag down.

The four runners

For two to 4 players around one table: each takes a ring and a horse, and the race goes to whoever keeps the steadiest beat.

1Red silks on a cocoa-brown horse
2Navy silks on a black horse
3Orange silks on a grey horse
4Green silks on a chestnut horse

Lane colour carries through the jockey, the saddle cloth, the pump-house lid, the pull ring, the number on the paddle and the flag, so every player can find their own horse at a glance.

Lanes two to four at the start: black, grey and chestnut horses in their fenced lanes, the pump houses behind — On the line, each horse behind its own fence and in front of its own pump house.

Rhythm, not speed

Each full pull swings the drum and moves the horse one notch. The drum needs about 0.12 s to fall back; pull again before its clack and that pull is wasted. A steady 2.5 pulls a second never loses one.

Tap Pull in a steady beat.

0 of 19 notches, 0 pulls lost

Fingers hooked through lane one's red ring, pulling it back from the pump house on a dining table, with a mug and a bowl of popcorn — One finger through the ring, a short tug, let go. Our kids learned in one race that yanking gets them nowhere. The steady one won.

The finish end of the course: lane one's red flag up, the other lanes' flags still lying down on their posts — The finish end. One flag up is the whole verdict; the other three are still lying down.

Up close

At 15.3 × 18.9 × 7.3 in, it covers about the same table space as a board game box opened flat, with room for four players to sit along the start end.

Low view along the lanes: horses at different notches, white rails and the toothed track — Eye level is the best seat in the house: the nods, the paddles and the flags all read from here.

Lane one's horse and red jockey on the dark sled, the toothed track beside it — Flat-cut horses, like the old carnival tin ones, each with its jockey in lane colours.

Lane one's horse at the finish post with the red flag swung upright — The flag only goes up on the last notch, so there is never an argument about who got there.

Four lanes and a finish arch

4: racing lanes with white rails and a toothed track
4: horses with jockeys, each on a numbered sled
4: pump houses with a weighted drum and a pull ring
4: finish posts with lane-colour flags
1: FINISH arch, lettered on both faces

Size: 15.3 × 18.9 × 7.3 in (388 × 480 × 185 mm)
Weight: 2.5 lb
Lanes: 4, each 4.3 in wide
Race: 19 notches of 10 mm to the flag
Pull: about 2 in on the ring per notch
Drum return: about 0.12 s, by four M10 steel nuts
Rhythm: 2.5 pulls a second always counts; above 4.3–4.6 pulls are lost
Material: PLA

The whole course on a dining table under a hanging lamp, with lemonade and a bowl of popcorn

Good to know

How many people can play?

Two to 4. Each player has a lane, a horse and a ring; empty lanes simply sit out the race.

Why didn't my horse move?

The ring was pulled again before the drum had swung home. Let the ring go, wait for the clack, then pull. A full pull is about 2 in.

What swings the drum back?

Gravity. Four M10 steel hex nuts sit in pockets on the drum's arm, and their weight returns it after every pull. There are no springs anywhere in it.

Can a hard yank cheat the race?

No. A lock on the sled drops into the next notch of a rack in the lane, so the horse never coasts past one notch however hard the ring is pulled. Pull firmly; there is nothing to gain by yanking.

How do I start a new race?

On each lane, lift the orange grip behind the horse, slide it sideways, push the horse back to the start, slide the grip back and tip the flag down.