The string that comes with the Eibos Filament Dryer was not a pleasure to interact with. It came out under normal use and gave me the gumption to make a better replacement. I wanted a spring loaded knob, thinking it would be much better to interact with. So far, I am very happy with this mod/fix.

The spring is from a typical clicky ballpoint pen.

The threaded brass insert is an M3x0.5x4LG.

The screw is an M3x0.5x10LG socket head cap screw

I printed it in ABS because the dryer can get quite warm. It is meant for drying up to PA/Nylon after all.