Flossing A Snorkel Tube
It is not uncommon to find a Sheaffer Snorkel tube that is so clogged with dried ink that you cannot get ink to flow through it. Soaking and an ultrasonic cleaner can often help but can't always clear the clog. The best way to remedy this type of clog is to make a flossing tool that you can use to clear the breather tube manually.
Take a piece of piano wire that is 0.020" in diameter and about three inches long. Find a piece of scrap dowel rod and drill a hole in the end with a #76 drill bit 1/2" deep. Epoxy the piano wire into the dowel. The scrap dowel rod will give you something to hold onto and give you the ability to twist the wire.
Start from the back end of the breather tube. If the feed inside of the tube is not damaged, it should extend beyond the tube. The inner feed is shaped like half a cylinder with an ink fissure cut into the flat surface that runs the entire length of the Snorkel tube. This leaves just enough room for the piano wire to work its way through. As you start to work your way through the tube, twirl the dowel between your fingers back and forth. This will assist in breaking up any obstructions. Doing this under running water also helps. Once you have run the piano wire up and down the inside of the tube a few times, take the wire out and attempt to blow through the tube. If you can blow through the tube, then you now have the obstruction cleared. If you cannot blow through the tube, keep working the piano wire until you have cleared the obstruction.
Once the obstruction is cleared, you can now finish cleaning the inside of the tube with Rapido-Eze in the the ultrasonic cleaner. The last trip through the ultrasonic cleaner will ensure that you get all the remnants of what was causing the clog. The ink fissure in the tube feeder is too small for your tool to get into and now that you have cleared any blockage, the Repido-Eze and the power of the ultrasonic cleaner will clear out any dried ink. Finally, flush the tube thoroughly with water to remove any remaining Rapido-Eze