How to identify a red hard rubber fountain pen and how to service it safely. Red hard rubber is one of the most brittle of vintage pen materials, easily broken unless you know what precautions to take.
I found the part just below the thread would very likely shrink if you overheated it even slightly, especially on cheaper celluloid pens. So I warp some paper tape to keep this part from being heated.
This is not an issue with hard rubber, though. Localization of heat is desirable in any case. Quality heat guns typically come with an assortment of nozzles, allowing for a suitably narrow air stream.
