Mach Bloc & Powermask Masking Compounds

MachBloc™ HVOF masking compound was developed to withstand the rigors of the HVOF plasma spray environment.  MachBloc™, in the uncured state, is a soft, conformable putty-like material. Machbloc™ is great for masking holes, grooves, key slots or any unique configuration for both plasma spray and HVOF processes.  Once cured MachBloc™ becomes a strong, abrasion-resistant mask allowing users to take full advantage of HVOF coating technology.

MachBloc™ features include:

  • Extruded profiles easily fill holes, grooves etc.
  • MachBloc™ is instant, flexible, and economical, allowing for quick turnarounds on small or large runs.
  • Halogen & chloride free for aviation applications.


  • Maximum Temperature: Continuous use - 625 F degrees, Peak - 900 F degrees
  • Cure Cycle: 25 minutes @ 250 F
  • Density: 50 lbs/cubic ft
  • Free Chlorides: < 1 PPM
  • Free Halogens: < 1 PPM
  • Cured Tensile Strength (3 mm thick): 6.9 MPa
  • Hardness (Shore A): 55 Degrees
  • Shelf Life: 6 months @ 72 F in sealed container

Praxair PowerMask™

We also offer Praxair’s PowerMask which is a liquid masking compound that is painted on with a brush.  PowerMask is a versatile, easy to use silicone based masking compound that prevents bonding of unwanted thermal sprayed particles.

PowerMask is ideally suited for flame, arc, and plasma spray systems where high velocity spraying is not being used. In these lower velocity applications, PowerMask is ideal because it is economical and all overspray is removed when PowerMask is peeled off of the substrate.