silicone tube cap metal liner

thingiverse

Many tubes come pre-packaged with a metal foil seal that gets punctured before use. The main issue lies in the shelf life after the tube is opened. Update: February 2020 saw the addition of a replacement nozzle cap. Manufacturers' original tube caps split in two, so I came up with an oddball thread diameter - M11.5x1.25. Scale the diameter of the STL model if it's not correct for your tube. This solution uses an aluminum foil metal liner for silicone RTV tubes and similar materials. The solvent used in RTV tubes diffuses through injection-molded plastic screw caps. Thin metal foil stops this, dramatically extending uncured material shelf life. For me, uncured urethane rubber with toluene is the worst - it goes bad within weeks. Use epoxy or another adhesive to attach aluminum foil to the flat print bottom. The PLA/metal liner design tilts slightly about the center ball. Evenly distribute sealing force on the tube's end. A disposable nozzle for tubes comes included, using an M12x1.25 thread. I'm not sure how common this size is, but you can scale any axis before printing. Finally, PLA works, but a filament with less creep deformation would be better. Designed in Fusion 360. Printed on a Cetus MK2 Extended. Happy printing, Peter