Auxiliary Materials
Breathers, bleeders and air paths
Breather materials maintain a connected air path under the bag; bleeders additionally accept controlled excess resin. One material can perform both roles only when the process allows it.
In simple terms
Breather materials maintain a connected air path under the bag; bleeders additionally accept controlled excess resin. One material can perform both roles only when the process allows it.
Best for
Vacuum continuity, volatile removal and controlled resin management.
Watch out for
A breather must remain continuous to the vacuum port. Excessive bleed can reduce resin content; blocked or compressed breather leaves trapped air.
Typical applications
Wet bagging, prepreg debulk, oven cure and autoclave bagging.
Related tools
Use the calculators to turn these concepts into preliminary engineering estimates.