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Thermal spraying is a technique first discovered in the 1800s. Today it is a process used in a wide range of industrial processes and for countless applications. The purpose of thermal spraying is to apply a coat on a surface in order to reduce or enhance different mechanical or thermal properties. In many cases not all surfaces of a part are subject to be coated. These areas must be covered by a protective masking. There are a number of different masking methods available today, each with its unique benefits and disadvantages. The work conducted in this thesis is investigating how to optimize the masking of a jet engine combustion can which is to be processed in a plasma coating process. The current masking method is a disposable flame resistant tape. A new masking solution must withstand abrasive grit blasting and the thermal spraying process. Other processes are outside the scope of this thesis. The method used has been to gain knowledge from a thorough literature study, advice from engineers with many years’ of experience, collecting of data and performing several tests. Choice of a material that can withstand both extreme wear from abrasive blasting and extreme temperatures in the plasma spraying process has been a challenge. Silicone rubber, POM and Teflon has indicated sufficient properties fit for purpose. The new solution, consisting of a capsule in two halves and a silicone rubber tube, has been suggested. A prototype of the capsule was processed in a CNC milling tool in the workshop at Mälardalen University. The prototype has passed the tests included in this thesis with sufficient results. The material of the capsule was meant to be Teflon but POM (Acetal) showed unexpected sufficient results from the thermal test. Manufacturing of the capsule can be performed by several methods including; milling, lathing, 3-D printing and molding. The silicone tube with desired dimensions has not been tested due to difficulties in finding a supplier which could offer test samples within the time frame of this thesis. However, tests indicate that silicone rubber is promising as a part of the final solution as the usage of flame resistant tape would be reduced by 100%. The new masking solution is reducing factors as time consumption, material consumption, environmental impact and agility in handling and application.