# A bobbin wound twice, and the ridge where it shows

> A bobbin's thread changes colour partway round — grey underneath from a job that finished, bright teal wound fresh on top, the join a small raised ridge between the two.

August 22, 2026 · https://justog.club/stories/the-bobbin-wound-from-a-different-job

One bobbin, printed small on the chest. Most of its thread is a flat grey. The last third is a
bright invented teal. Between the two, where the winding changed, a small ridge sits raised off
the surface of the reel.

Nobody rewound the whole bobbin to match the new job. They wound over what was already there.

## What actually happened to this bobbin?

Two different jobs went onto it, one after the other, without emptying it in between.

The grey thread was left on the spool once whatever it was sewing was finished — not much of it,
not worth binning a working bobbin over. Rather than stripping the reel bare, the next colour was
wound straight on top, thread over thread, until the fresh layer covered enough of the barrel to
sew with. The grey underneath didn't go anywhere. It's just wound under, not over.

## Why is the join a ridge instead of a clean line?

Because winding thread over thread adds a layer, and a layer has thickness.

Where the teal starts, it sits on top of however many wraps of grey were already there, so the
diameter of the spool steps up slightly at that point rather than staying constant. Thread wound
evenly from an empty bobbin builds up smoothly from the barrel outward; thread wound onto a
partial one carries a visible step at the point it started. That step is what reads as a ridge.

## Why keep the old colour on there at all?

Because a bobbin with useable thread on it is a bobbin you don't have to rewind.

Emptying a spool just to start clean costs time and wastes thread that still works. A machine
doesn't care what colour is underneath — only the outer layer, the one actually feeding through the
needle, does the sewing. The grey stops being relevant the moment the teal covers it, in the same
way [a repair sewn in whatever thread was to hand](/stories/the-repair-done-in-the-wrong-thread)
doesn't wait for a matching spool before it gets used. It just hasn't been unwound to check.

## Whose thread colours are these, and is there anything to clear?

Nothing. Thread colour isn't owned by anyone.

A grey-to-teal bobbin is a description of a physical object, not a reference to a brand, a
proprietary dye lot, or anyone's identity. If a design specified an actual thread manufacturer's
branded spool end, printed logo and all, that would be a different, licensable ask — this is a
plain reel with invented colours standing in for whatever two jobs actually used it, the same way
[a replacement zip in whatever colour was on hand](/stories/the-zip-replaced-with-the-wrong-colour)
needs nobody's permission to be mismatched.

## Does this work with other colour pairs, or is grey-to-teal the whole idea?

The mechanism holds for any two colours; what changes is how visible the join reads.

A pale colour wound over a dark one shows the ridge as a hard, high-contrast line. Two closer tones
make the same ridge but a quieter one — present if you look, easy to miss if you don't. That's a
different kind of visible-if-you-look than
[a bleach mark whose edge only shows in the right light](/stories/the-bleach-spot-you-kept),
but the same idea: proof of an earlier state, sitting right under the current one.

## Isn't a bobbin too small and too specific to read as anything?

It reads as a cross-section before it reads as sewing equipment at all.

Two colour bands split by a ridge is a legible shape at a glance — a small object, cleanly cut in
half by something that isn't quite a straight line. Knowing it's a bobbin and knowing what the
ridge means both deepen it, but the shape carries even without either.

## Does it print well at this size?

Yes — it's two flat fills and one hard edge, which is exactly what survives small.

The barrel outline and the winding texture need to stay linework rather than soft shading, or the
thread pattern fills in below the weave's floor and the two colours blur into each other instead of
meeting at a visible step. Two inks plus the near-black garment is enough; a third would crowd a
print this size without adding anything legible.

## How do I get one made?

Describe the bobbin at [JustOG](/) — the two colours, and where along the reel the join sits. 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).

Somewhere under the teal, there's still enough grey to finish a small job, if anyone ever unwinds
that far.