I know this will set a few of you off but I did it, I admit it, and I promise not to do it again.......well maybe not. I bought a premade cork handle. What a piece of @&%$ !!!!. Now, how do I fix it? Both ends crumbled when I reamed it out, and I went slowly and carefully. I was able to hide all but the butt end. I left myself a little working room but the cork seems very brittle. I have seen composite cork butt caps. Do these glue in, over, mount flush? is there a better way? I know that even if I can sand it smooth without any more mishaps that it won't hold up without some kind of protection.
Thanks,
Tom

Tom,
It sounds like you got a bad piece of preformed cork. But to answer your question you can slide a butt cap over the end of the cork and glue it,that is if it doesn't keep breaking down. If it does then I would say trim it down to the blank and glue the butt cap on.
Neal's Fishing Product

I've got about 10 rods behind me and all were made with the preformed cork. It really sound like you got ahold of bad or old cork. I'm going to switch over to turning my own someday but I've had really good luck with the pre made ones. Where did you buy it?

I've used the St. Croix preformed handle kits extensively and have never gotten a bad one. St. Croix uses a burl cork ring for the bottom of the handle. I recently started making my own handles from cork rings, and I incorporated this technique into my own handles. The burl cork is VERY tough and chip resistant.

Here's what I do: I put the burl ring on a bolt and nut, chuck it into my drill press, and use a double-cut flat bastard file to for shaping - I don't have a lathe. I turn the ring to a slightly smaller diameter than the rest of the handle, give it a pleasing shape depending on the type of rod it's going on, and then sand with 220 grit sandpaper to smooth it. All of this is done in the drill press. I then epoxy it to the end of the rear grip, center it visually, clamp it in my cork clamp, and clean off any excess epoxy. After the epoxy has cured, I use 220, then 400 grit sandpaper to blend the regular cork handle into the burl ring. I tried to do the opposite (blend burl into regular) but the burl is VERY tough to sand. Works for me!