I've been using the same set of Hysol nozzles for well over three years now...one short and one long. Works if you have a couple simple things available...compressed air, a sealable cigar tube, and acetone.

After I'm done with the Hysol, I remove the tip from the gun (being careful to wipe down the tip of the glue cartridge with an acetone soaked cloth, and then replace the tip seal cap on the cartridge). I grab a handful of paper towels or an old rag with the end of the nozzle pointed towards the center of the bunched up rag(s). Using an air nozzle, I carefully blow out the mixed glue from the tip until it runs clear. Make sure the air nozzle seals tightly against the base end of the tip, or you'll get a serious back blast of epoxy!

After that I insert the tip into a large ring gauge cigar tube - the 50+ Churchill size gauge metal tubes work best - that is 3/4 full of acetone. Screw the cap on, shake vigorously, and remove the tip with some needle nose pliers. Wipe the outside down with a rag and store until needed again.

I've been able to reuse the acetone for 3-4 cleanings before I need to replace it. One note - don't store the nozzle in the sealed tube for too long, or it might dissolve - I've had it happen a couple times.

Works great for me.