Lol, after seeing the other post, I thought I'd post about my (opposite) problem - I have some cab mandrels which have no 'nub thingy' in the middle, and I lose nearly every cab! As soon as I do anything even remotely tricky (raking a dot! In one case, placing a dot and pulling gently on the stringer as I was melting it off!), the bead release breaks and I lose the cab. I have tried filing the surface to create extra 'grip', to no avail. I've now asked a friend to try and weld a nub onto it, but no idea if it'll be as easy as I imagine. Any clever ideas?
I make mine successfully on the end of a regular mandrel. I tried a cab mandrel and find this method easier.
Maybe try a harder bead release like SuperBlue Sludge. I could never get anything off a mandrel using that bead release. Might make the cab stick better? The other option may be to drill small holes into the cab mandrel so that the glass might be pressed a little into the holes? ???
Oh, intriguing, Sal....I guess I could, and then grind it down...hmmmm...........
I do make them on the end, too, but they have to be pretty much exact in size, and I haven't got the patience to faff :/