You can create a Disable Collision constraint for nCloths, passive objects, or vertices to prevent them from colliding with all other nCloths, passive objects, or vertices. This constraint is useful when you want to improve the performance of your nCloth or you want to avoid collision geometry crossovers.
You can also use the Paint nCloth Attributes Tool to create a Collide Strength vertex map or texture map that dampens or disables collisions on nCloth and passive collision object components. See Paint nCloth property maps
To create a Disable Collisions constraint
The nCloth objects, passive objects, or vertices you selected no longer collide with any other objects or components that share the same Maya Nucleus solver.