The art of separating dirt from patina

Restoring technical objects requires dedication, sensitivity and a lot of time. However, time is a factor that can be weighed against money in any industry, which is why restorers are always looking for ways to optimise their work processes without compromising the result.

A restorer will always do everything possible to protect the historical object from further damage. The pivotal point of a restoration is the preservation of an authentic historical appearance and the reduction of physico-chemical risk factors. In order to gently remove unsightly and destructive crusts and soiling from historical objects, restorers often adapt processes from industry. In the restoration of wrought iron objects, the Dresden State Art Collections have been working together with the Dresden Fraunhofer FEP for many years.

The Fraunhofer FEP analysed the vacuum suction blasting unit from Systeco to test its suitability for restoration projects. It proved to be well suited in terms of dosing and visibility of the surface to be treated during the process. In addition, it proved to be very positive that potential hazardous substances remain in the cycle, are filtered and sieved by suction. A central parameter in the investigations was the blasting abrasive used; 13 different blasting abrasives were tested. Surprising correlations and findings emerged during the tests, which in turn revealed new application perspectives in retrospect.