I have used epoxy. In the future I will use clear silicone adhesive. It will bond tight, gives you a few minutes to position the knot, is waterproof, and makes it a whole lot easier to remove the knot should the need arise.
Get a good waterproof glue. There are a zillion. I don't trust hot glue because it doesn't seem to set very firmly. I think it might come loose after a time. But, others here have used it without any issues. Epoxy is awesome, but it is permanent. If you decide to change a knot you won't be able to preserve an old one set in epoxy. You will probably have to drill it out. You will never get it hot enough to break the epoxy bond without melting or damaging the handle. So, other glues might be a better choice if you want to change knots. I use golf club shafting epoxy mostly for shaving brushes. It has serious strength and I've never had the 24 hour variety fail in a golf club if I mixed it well (I have had 5-min epoxy fail in a driver). And, I don't intend to keep the knot if I replace it. But, other glues to consider that won't be as permanent: E6000 Beacon Power-Tac Beacon Quick Grip (if you are in a hurry) Good construction cement from your hardware store; try to get the clear variety
I use silicone almost exclusively now unless someone wants to use epoxy. If you ever have to change out a knot, you can usually reuse the knot if it was set in silicone. If it was set with epoxy, you will have to destroy the knot.
I have used both epoxy and silicone. I prefer epoxy. The 15 minute gives plenty of time for adjustments. Both are good....just my preference.
+1 for Silicone. I have used this brand and one other on about 30 brushes now. I don't believe there has been a failure reported yet.
I've used a hot glue gun in the past, and it worked well. I had to take the knot out and put another in, and tried hot gluing it, with newly acquired glue sticks, and it just wouldn't hold. Not all glue sticks are made the same. I gave up, and used Gorilla Glue 5 Minute Epoxy, and it worked fantastically. The trick is to let it start to thicken, before application, or it will be too runny.
I went by the title of epoxy or hot glue, so I chose epoxy. But silicone is another good choice as others have mentioned.
Thanks, I've decided to "re-glue" using silicone, in particular had some G.E. stuff. Waited 3 days prior to using. So far so good will otherwise but feel confident on recommendations.