How to overcoat mineral oils such as Cutek™ CD50 with Intergrain® UltraDeck®

Cutek™ CD50 is marketed as a coating that “penetrates deeply into wood”. One method Cutek™ uses to do this is to use an oil that does not dry but that initially penetrates and then continually migrates within the timber. As such, these mineral oils have the potential to migrate from within the timber back to the surface and pose potential issues when recoating the timber with other products. The initial use of a non-drying mineral oil coating such as Cutek™ CD50 may result in problems with any subsequently applied coating system. Even if the timber appears to be dry and weathered, it will still contain some of the Cutek™ CD50 oil.

Surface preparation is vital when attempting to coat over timber previously treated with Cutek™ CD50. The timber must be prepared as follows. This preparation is for exterior timber only.

  • Wash timber with Intergrain® PowerPrep™. Follow all label instructions.
  • Then wash with Intergrain® Reviva®. Follow all label instructions.
  • Allow timber to dry thoroughly.
  • Check to see if water is beading on the surface. Water should soak into the timber readily. If water beads on the surface then further cleaning is recommended.


This preparation step is extremely important as it may help to remove some of the Cutek™ CD50 from the surface of the timber. However there is no guarantee of complete removal of Cutek™ CD50 oil through this process.


Once the above surface preparation is complete:

  • Allow timber to fully dry.
  • Apply one coat of Feast Watson® Proofseal™. Follow all label instructions.


Feast Watson® Proofseal™ is a solvent based sealer designed to seal in tannin and natural oils in timber. It may also help to seal in Cutek™ CD50, minimizing its potential to migrate to the surface of the wood. However, there is no guarantee it will completely prevent migration of Cutek™ CD50.


Once you have competed the above process, apply either Intergrain® UltraDeck® or Intergrain® NaturalStain®.


Cabot's Premium Woodcare Brands will not accept responsibility for coating performance problems that occur if Cutek CD50 has been previously used.