One glue solution for the ferrule problem that I use is "Flex Coat"
It is a 2 part epoxy that remains somewhat flexible and is used in fishing rods for coating the thread holding down the eyelets.
Down side, it takes time to set though. Several house to set and then about 24hours to finish.
They make a 5 minute flex coat also. Will try that later
It is self leveling, so having the rod turn slowly at first keeps the glue even and not puddling.
Fishing rod supply businesses, websites have the product, and info.
I use just enough to coat the entire surface of the ferrule.
Push in and twist at least 30 degrees and hold for a short time so it doesn't back out.
Haven't had one come loose yet.
I can remove it later also....drop tapping on a block of wood works after numerous taps.
I have used it on ferrules on the 1/4" rods and rods for SLE and Super Sonic.
I have also used Zap a Gap. It has worked great so far.
I also use Flex Coat with wrapping the rod ends, about 2 to 3" or so, of some of the rods that have cracked or chipped, using rod wrapping line and the tools for wrapping fishing rods.
Works great until a new rod(s) is ordered and to have emergency rod(s) available just in case that would have been otherwise thrown away.
With the colors of wrapping thread available, I use color threads to match the sail colors.
Rod bling, yeah baby!
It does add a just tad bit of weight though.
Steve