# A running chalk tally is the only maintenance log there is

> A hand-chalked running total on a workshop wall, rubbed out and rewritten so many times the old figures still show through, is the only record of how hard a lamp has worked.

August 21, 2026 · https://justog.club/stories/the-lamp-hours-on-the-wall

Near the top, one clear number in chalk: `1,940`. Below it, a dense block of older marks — white and
rust-orange, layered over each other, rubbed out and written again so many times that nothing in the
block is readable any more.

The top figure is the only one anybody needs. Everything underneath it is just proof that the top
figure is real.

## What is this number actually counting?

The hours a projection lamp has been switched on and burning.

A lamp is a consumable with a working life measured in hours rather than in years or in shows run.
Somebody has to know, at any point, roughly how many hours are left before it's due for replacement —
and the simplest way to know that is to add to a running total every time the lamp goes on.

## Why chalk, on a wall, instead of a logbook?

Because a logbook gets carried off, left in a drawer, or lost outright, and a number written on the
wall where the lamp actually lives cannot go anywhere.

Whoever's on shift walks past it on the way to the lamp house anyway, which means the total gets
updated by the person doing the work, at the moment the work happens, rather than filled in later
from memory — the same reason
[a handwritten instruction stays taped up rather than filed in a manual](/stories/the-house-lights-on-a-cue).
Chalk rubs out cleanly for the next total, and grease pencil holds up against a bit of grime.

## What's the point of the half-erased marks underneath?

They're an accident, and they're also the only thing that makes the top number trustworthy.

Rubbing out a chalk figure never lifts it completely — a faint version stays, and the next total gets
written over it, and the one after that over both. Nobody set out to keep this record; it built up
because a wall in the same room as
[the bench where the print itself gets checked by hand between shows](/stories/the-rewind-bench)
was reused rather than replaced. But it means the current total sits on top of visible evidence that
it's part of a sequence, not a number somebody made up on the spot.

## Does a maintenance total like this belong to anybody?

No — a running count is a fact about one lamp in one building, not a design or a piece of writing
anybody could claim.

There's no equipment brand named anywhere in this design, no maker's mark, nothing that identifies a
specific machine — just a number and the wall it's written on. What's being reproduced is the
*format* of a chalked total, common practice in any workshop that tracks a consumable by hand, not a
particular record from a particular building.

## Whose number should actually be on the shirt?

Whichever total means something to the person wearing it — the current figure isn't the only one
that works.

A specific hour count from an actual piece of equipment somebody maintains, a number that happens to
match a date or an age, or a total invented purely to look plausible on the wall all work; the design
doesn't require the number to be real, only for it to sit at the top of the block the way a genuine
running total would.

## Isn't a maintenance log a strange thing to want printed on a shirt?

It reads as a strange source and an obvious shirt at the same time, which is most of why it works.

The appeal isn't the number itself, it's the layered evidence underneath it. Anybody who has kept a
running count of anything by hand — on a wall, in a margin, on a whiteboard nobody else was allowed
to touch — recognises the object immediately, in the way
[four seconds is recognisable to anyone who has ever had to do several things in order under
pressure](/stories/four-seconds-to-change-over), even without the specific job.

## Does it print well?

Yes, in two layers that print very differently from each other.

The top figure is a clean, legible numeral and should stay exactly that sharp — it's the one part of
the design doing a job that has to work at a glance. The palimpsest underneath is the opposite: it
wants to be messy, overlapping and slightly illegible, one of the few places on this whole site where
more noise in the print is correct rather than a compromise.

Olive, faded black and rust all suit a workshop wall. Two inks: one clear tone for the top number,
one warmer, dustier tone for the layered marks beneath it.

## How do I get one made?

Describe the wall at [JustOG](/) — the number on top, and how much of the older writing should still
show through. Pick a direction, drag the crop frame, see it composited on the real garment, and it's
made to order and shipped.

Designs other people have published are in the [shop](/shop).

Somebody rubbed out a smaller number to write `1,940`, and somebody will rub that out too.