A lock manufacturer needed machined brass lock bodies, casings and plugs critically clean before assembly — free of the swarf and oil that cause pins to stick, rejects to climb and finished locks to look second-hand. This is the documented trial process (T-3173) that solved it, stage by stage, with the photographs to prove it.
The contamination, understood before it was attacked
Nothing about this soil load is exotic — what makes it stubborn is how the three contaminants work together.
Fine brass swarf
Machining leaves a fog of fine brass chips and needles through every drilling, pin chamber and thread. In a lock, one retained needle is a mechanism that binds — this is functional contamination, not cosmetic.
Cutting oil — the binder
The oil film is what turns loose swarf into stuck swarf: it glues the fines to bores and casing walls, so air-blast and vibration can't shift them. Break the oil and the swarf loses its grip — which is why degreasing leads the process.
Machining pastes
Lapping and forming pastes don't blow off and don't rinse — they must be chemically dissolved or lifted from the surface they've bonded to. This is what sets the chemistry requirement: detergency plus surface-adhesion release, not just oil splitting.
The insight that shapes the whole process card: the swarf is not the problem — the oil holding it is. Dissolve the binder and paste load in a hot chemical stage, and the mechanical actions (spray, flood, rotation) can then evacuate the freed solids. Attack the swarf first and you're scrubbing glued chips.
The process: three stages to critically clean
| Parameter | Stage 1 — Hot degrease | Stage 2 — Rinse | Stage 3 — Dry |
|---|---|---|---|
| Action | Spray wash + injection flood wash (IFW), hot solution degrease | Identical spray + IFW mechanics, run on water | Hot air + vacuum |
| Medium | Brulin AquaVantage 1990 GD, 4.0% | Demineralised water | — |
| Temperature | 60 °C | 60 °C | 110 °C air |
| Filtration | 50 µm bag | 25 µm → 10 µm staged bags | — |
| Movement | Basket rotation, intermittent | Basket rotation | Rotation under airflow + vacuum |
Two details carry the result. The rinse deliberately repeats the wash mechanics with water — same spray, same injection flood through the bores — so anywhere chemistry reached, rinse water follows; nothing is left to dry into a pin chamber. And drying finishes with vacuum as well as hot air, because a blind hole holds its water against airflow alone; pulling the pressure down evacuates moisture from exactly the features that matter most in a lock. That combination — every stage reaching every feature — is what "critically clean" means in practice, and it is the difference between a part that is clean and a lock that works.
Before and after
The results
The hardware and chemistry behind it
Misonics UltraWash — multi-stage cleaning system
Spray, injection flood wash, ultrasonics, rinse and hot-air/vacuum drying in one enclosed sequence, with basket rotation through every stage and staged filtration keeping removed contamination out of the process. Sized from cell to production line.
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Brulin AquaVantage 1990 GD
Heavy-duty aqueous degreasing chemistry with the detergency to dissolve cutting oils and machining pastes and release bound swarf — free-rinsing, so nothing is left behind on a critically clean surface.
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