JOS Blasting Machines

JOS blasting machines and Whirl Blasting Technology for Sensitive Surfaces

JOS blasting machines are primarily used where a surface needs to be cleaned without unnecessarily removing too much of the existing material. The JOS process is a form of vortex blasting technology: a mixture of air and abrasive media, combined with water, is directed in such a way that the jet does not strike the surface exclusively at a single point or head-on, but instead moves in a rotating or spiral pattern.

This method is particularly useful for historic and delicate surfaces. Typical applications include natural stone, sandstone, stucco, facade reliefs, sculptures, fountains, historic masonry, and other restoration projects. Depending on the substrate, soot, dirt, weathered deposits, or unsuitable old coatings can also be treated using appropriate settings.

Why Whirl Blasting Works Differently

With a conventional straight jet, the energy is more concentrated on a small impact zone. The JOS principle distributes the effect more broadly and in a more controlled manner through the vortex. Combined with low operating pressure, this allows a surface to be cleaned gradually without immediately producing a high ablation effect.

However, this does not mean that the process is fundamentally damage-free. Even a gentle blasting process can alter unsuitable or already damaged materials. The actual material removal depends, among other things, on the abrasive media, grain shape, hardness, working pressure, distance, water addition, and dwell time.

JOS Blasting for Natural Stone and Historic Facades

With natural stone in particular, strength and the degree of weathering vary considerably. Sandstone, limestone, marble, and other types of stone react differently to mechanical stress. In the case of historic facades, joints, plaster, paint finishes, and repair areas are additional factors to consider.

Therefore, the cleaning process should not be determined solely by the visible degree of soiling. What is more important is which surface layer needs to be preserved. For objects relevant to historic preservation, a preliminary evaluation based on materials science or restoration principles may be advisable.

Water addition for dust suppression and process control

In JOS blasting, the addition of water helps bind dust and can simultaneously influence the surface finish. The goal is not to saturate the surface as much as possible, but rather to introduce water into the process in a controlled manner. Excessive amounts of water can place unnecessary strain on sensitive building materials and result in additional cleaning or drying efforts.

Particularly with porous building materials, it is important to determine how much moisture is absorbed and whether salts, the risk of frost, or subsequent coatings need to be taken into account.

Selecting the Right Abrasive Media and Grit Size

The abrasive media are a key factor in the surface finish. Fine and suitable abrasive media allow for more controlled processing than coarse, sharp-edged, and very hard abrasive media. At the same time, the abrasive media must be dry, free-flowing, and compatible with the respective equipment.

The right choice depends on the type of contamination and the surface. A firmly adhering coating on sturdy stone requires a different setting than soot on delicate stucco or a thin deposit on a historic sculpture.

Using JOS Blasting Technology Properly

The strength of this process lies in its adjustability. Working pressure, abrasive flow rate, water, distance, and movement can be combined in such a way that the cleaning process is gradually adjusted to achieve the desired result. Especially when working with valuable materials, the focus should be on controlled operation rather than maximum speed.

This category is therefore particularly relevant for users interested in JOS blasting machines, JOS blasting technology, and gentle whirl blasting. Since no specific JOS devices are currently listed in this category, the information provided here serves as a technical guide to the process and the key selection and setup criteria.