you can get away with cardboard and masking tape if you put a hole at one end of the tube and the other end get the gas hose, just set the flow to keep it filled with fresh gas. you just have to keep the flow, aluminum foil is also used. lots of option, be creative and find one that works for you or you can look to the market for the many premade options. some more $$ than others but lots of options out.
great work on the pipe's