Sheaffer’s TM (Thin Model) Snorkel Gives Collectors Plenty To Get Excited About

by Paul Erano

Some vintage pen collectors dismiss Sheaffer’s TM Snorkel a little too easily. Without hesitation, they repeat what they’ve heard over and over: it is the most complicated pen ever made, it is too slender, and its ink sac is hair thin. Restoring one is a nightmare. And, of course, its nibs are stiff and ungiving. Yet other collectors see the Snorkel’s complicated nature and thin profile as the product of outstanding design and engineering. In their eyes, the pen’s components fit together like pieces of a puzzle, forming a larger and more interesting picture. Add a touch of mystery (what was the Snorkel’s real purpose?), unravel the pen’s construction, throw in some rare and unusual barrel colors, a demonstrator model, and a few esoteric nibs, and I think it adds up to a vintage pen that gives collectors plenty to get excited about. 
Snorkel’s origins date to 1949, the year Sheaffer’s pneumatic Touchdown model replaced the venerable piston pens the company had offered since the 1930s. Outwardly, Touchdown and the earlier piston pen looked similar, but they filled using entirely different methods. A rod and piston created a vacuum and held ink in the barrel in the piston-fill model. Touchdown’s larger diameter tube created air pressure to deflate an ink sac. The new Touchdown was made from injection molded plastic, and it was full bodied at first. A thinner model appeared soon afterwards and was given the TM (thin model) designation. 

The TM Snorkel was introduced in 1952, and without the snorkel extended it looked almost exactly like the TM Touchdown. Both pens employed the same pneumatic-fill system that relied on an O-ring to create air pressure to deflate the ink sac. A groove in the metal tube at the end of the down stroke broke the airtight seal so that air rushed into the barrel and allowed the ink sac to expand. A small hole in the barrel equalized air inside the pen with outside air.
Snorkel’s extendable tube required considerable modifications to the pen’s internal mechanics, and these changes are what turned the new pen into something much more than a modified Touchdown. A hole in the feed allowed the snorkel tube to pass through freely, and a gasket at the mouth of the sac assembly kept things airtight. Grooves in the section align with ridges on the sac assembly to guide its movement, and an even thinner ink sac allowed the long spiral spring to fit in the same space inside the barrel. The metal sac housing was threaded. Finally, the barrel was made a tad longer to accommodate the new mechanism’s back-and-forth movement. The result was a durable, beautifully engineered, high-quality pen that worked without a hitch. The Snorkel’s mechanism is truly marvelous, and for this reason demonstrator models are extremely popular. For collectors who do not have a demonstrator model to enjoy, simply take a pen apart to see how it works works. But understand that much about the Snorkel is counterintuitive.