Dave,
The way you worded it I thought you were trying to get a pipe cleaner down the needle.
You are talking about the opening in the airbrush body where the needle goes correct? I never run a pipe cleaner in that area as pipe cleaners can leave tiny bits of material behind as cause problems.
I use the nylon Airbrusher's Brushes that they sell at Dixie Art, BearAir, and Coast Airbrush.
Mike
“Wisdom is the right use of knowledge. To know is not
to be wise. Many men know a great deal, and are all the greater fools
for it. There is no fool so great a fool as a knowing fool. But to know
how to use knowledge is to have wisdom. " Charles Spurgeon