Laser cleaning of injection moulds — how it works and when it makes sense
RC-Laser Team ·
How a laser removes carbon deposits and release agents from injection moulds, what it will not do and how it differs from dry ice.
Deposits on a mould are more than just a dirty mould
Injection moulds accumulate carbon deposits, burnt plastic residue, resins, release agents and outgassing deposits. According to a manufacturer of laser systems, material residue and release agents can cause defective details; this is promotional material, with no comparative data [1].
How a laser cleans a mould
Laser cleaning works by ablation: the beam is absorbed by the contaminant, which vaporises, while the metal reflects most of the energy. According to Wikipedia, laser ablation is one of the preferred methods of cleaning rubber moulds because it damages their surface minimally [2].
What we do on moulds
We clean injection moulds, injection moulding machines, cavities, slides, vents and hot-runner elements. We work on tool steel, including nitrided and coated steel, and on beryllium inserts. Cleaning is done directly on the injection moulding machine, without removing the mould.
Laser versus dry ice and mechanical methods
Dry ice can also clean plastic and rubber moulds without dismantling [3], so the lack of dismantling alone does not set a laser apart. The differences we describe on the service page are different ones: compared with mechanical cleaning and brass brushes, a laser does not change the roughness of the cavity, and compared with dry ice it does not cool the mould, which shortens the return to production. This agrees with the description of dry ice, in which sublimation absorbs heat from the surface [3].
What a laser will not do
A laser will not restore a surface structure that was damaged earlier: if the cavity was rubbed with a brush or over-polished, this will show after cleaning. Nor does it replace dimensional regeneration, because it removes deposit rather than adding material. On polished surfaces the laser has to be chosen so that the microstructure is not damaged [1].
What a job looks like
Analysis of the type of deposits and the condition of the mould, cleaning without disturbing the working surface, a quality test of the first moulded parts. An estimate from a photo is preliminary; we give the final price after inspecting the object on site.
Sources
- LaserPhotonics, “Why laser cleaning is essential for plastic injection molding machines” (manufacturer's promotional material)
- Wikipedia, “Laser ablation”
- Wikipedia, “Dry ice blasting”
Sources as of 2 November 2026.