Substrate interior pressure control method

A substrate coating method comprising:

• (a) positioning a hollow substrate having a first end and an open second end in a solution, wherein the open second end is submerged in the solution, wherein gas is present in the hollow portion of the substrate between the solution and the first end, thereby defining a quantity of trapped gas molecules;
• (b) removing the substrate from the solution;
• (c) changing the quantity of the trapped gas molecules by (i) withdrawing a portion of the trapped gas molecules, or (ii) introducing additional gas molecules into the hollow portion, wherein (i) and (ii) are accomplished through the second end of the substrate, thereby controlling the pressure of the gas in the hollow portion;
• and
• (d) depositing a coating on the exterior surface of the hollow substrate.