If you are using lacquer and dipping I might suggest that you use a dowel rod that fits the tubes and after dipping slide each section onto the dowel rod for drying. You might also want to wax the dowel rod to try and keep the lacquer from sticking to it so well. Make sure the dowel rod is sized to fit the tube so that you can turn the rod as the lacquer is drying. If you can't find -or make - a dowel rod of the right diameter, you can always "foul" the tube onto the dowel using a toothpick as a little wedge. Slide the tube onto the dowel, insert the toothpick and break off the excess. You only need to hold one end of the tube in place to allow the dowell to be turned a bit.
Surplus lacquer an easily be cleaned fro inside the brass tubes by using a barrel cleaning brush in the proper calibur of the tubes. I have used a .38 brush to clean many tubes. I mount it in a short section of the cleaning rod and put that into the drill press and spin away. Be careful of sharp edges though.
You can vary the length of the dowel rod to make it hold as many as you want - within reason. AND do not let the ends of the blanks touch.
I like the idea of spraying lacquer since that allows ME the ability to control how much and where the lacquer is applied. Just remember that any dust collected on the sticky lacquer will caus a lot of extra finish work. The inside of a large cardboad box lined with tacky paper works rather well. Spray adhesive on paper towels might be a good trick to use to try and catch any stray dust.
Again, just my .02 worth of an idea.