Mold cleaning or line cleaning: which are you buying?
Decide this before comparing anything. On a mold, the surface you clean is the surface that makes the part, so the damage you can accept is none, and the fill starts softer than the tool steel or the glaze it touches. Softer is not a guarantee: a fill that picks up hard particles, or works on a plated or mirror-polished face, can still mark it, so try a new fill on a test area first. On a ceramic or brick line the pressure is the opposite: the material is abrasive and the brush is a consumable.
Which jobs fall under this heading?
- Mold and die cleaning: release agent, carbonized residue, flash and rubber deposits on a polished or textured tool, often cleaned hot, in place, between shots. Nothing may mark the cavity.
- Ceramic and glaze lines: dust on green bodies before firing, glaze slurry and overspray on the line, kiln debris afterwards. The dirt is abrasive and constant, and the brush wears rather than the work.
- Brick, tile and building-material machines: heavy abrasive clay on the machinery rather than on the product. The brush is a maintenance consumable, and stiffness matters more than finish.
- Rubber and plastics processing: mold release and rubber dust, usually held on the tool by static.
Which fill for which surface?
| Surface being cleaned | Where to start | Why |
|---|---|---|
| Polished or textured mold cavity | Brass Wire or Phosphor Bronze Wire | Softer than tool steel, so the deposit gives way first. On a mirror polish or a plated cavity even brass can mark, so test it first |
| Hot tool, cleaned between shots | PEEK Filament or natural fiber | Keeps its shape at tool temperature, where nylon slumps |
| Green ceramic body before firing | Goat Hair or Horsehair | Lifts dust without marking an unfired surface |
| Glaze line and overspray | Nylon PA | Washes clean and does not carry pigment into the next color |
| Brick and tile machinery | PA66 Nylon or Abrasive Nylon | A stiff, replaceable fill against constant abrasive clay |
| Rubber or plastic dust held by static | Conductive Nylon or Anti-Static Filament | The charge holds the dust; removing the charge is the job |
How are these brushes built and mounted?
Mold work is mostly hand work with the tool locked out, so handle length, head size and tip protection make up most of the specification. Line work is the reverse: fixed strip or roller brushes bearing on moving product, where the mount and the path for removed material matter more than the head.
What usually goes wrong?
- Steel wire on a mold cavity. It removes the deposit and the surface finish together, and the finish is the part.
- A polymer fill on a tool still at working temperature. It slumps on first contact and leaves melted filament in the cavity.
- Using glaze-line brushes across colors. The fill carries pigment, and the next color shows it.
- Specifying a brick-line brush for wear life with nowhere for the clay to go. The clay packs the fill, and the brush stops working long before it wears out.
What should you send for a quote?
What the surface is and how it is finished, its temperature when it is cleaned, what is being removed, and whether the work moves or the brush does. For line brushes, add the working width and how the removed material leaves the machine.
