A better way? to keep RTV usable.

We did this at the "wheel chair joint" I worked for 4 years, and this seems to work. There were several procedures whereby we needed RTV but not very much, so preserving tube contents for subsequent use was desirable, otherwise, lots of waste

Instead of attempting to seal the tube with the factory cap, we'd take a screw approximating 3/16" --so quite large in relation to the tube opening--and about 1 1 /4" or so long, and stick it into the tube clear up to the head.

Next time you wanted to use it, you took a pair of pliers, twisted the screw to break it loose and pull it out. My theory is, that this created a channel in surrounding cured RTV. This, really, works quite well.

We did not normally use the supplied nozzles, but if you do, you can cut/ scrape / tear off the cured RTV and still screw it on there