You don't say which hysol you are using.Safest just to let it harden over night, Clean the tip with
acetone, just drop the works in a jar. then you have to pull the center out and blow or scub it. And watch for fire hazard with acetone, of course.
Helps to keep the cap on that cartridge clean too as one side can harden near the tip. no guarantee of even flow with that thing.