we have to manufacture a hollow composite component by using prepreg and 3d printed mold.
when we are applying prepreg on two half of the cavity and putting an inflatable flexible bladder inside to apply pressure.
How we can join the two halves to get a hallow components
You must place the prepreg plies on each half tool as accurately as possible, without exceeding the edges of each half tool; then, if you have a good inflatable mandrel, you must place on the mandrel along the "area where the two half tools close", a narrow prepreg laminate not less than 40mm wide (for a part with a volume up to 10 Litres) with the same number of prepreg plies that were applied to the half molds. Finally you close the two half tools and increase pressure (approximately up to 2 Bar) and adjust the curing cycle as indicated by the prepreg supplier, wait the indicated curing cycle and ready to release the part. Don´t use release agent with silicone. I recomend Airtech Safelease 30 release agents.