Complex sentence: To insure that the material is totally devoid of air bubbles, the entire mold/mold box may be placed in the chamber for an additional few minutes, this will assist the material in flowing into difficult areas of the mold/mold box.
Split into simpler sentences: To insure that the material is totally devoid of air bubbles you can place the entire mold/mold box into the chamber for an additional few minutes. This will assist the material to flow into difficult areas of the mold/mold box.