I picked up a really knackered bowls ball last year. And since I'd decided it was too hot to go out again I finally got to make my heavier carving mallet.
First off I took one of my beloved carboot 50p beech rolling pins and turned a section down to nearly fit down the hole in the bowls ball where the plastic caps had conveniently been broken off. I then sanded it until I thought it could be hammered on, turned a bunch of grooves into the place where the head would go, applied copius amounts of model aircraft grade Alphetic resin glue and with my heart in my mouth hammered the head on. I was convinced I would split the basically donut shaped piece of wood ( I'm pretty sure it's Lignum vitae , if not its some other super heavy, dense, impact resistant wood ) but it laughed it off which bodes well.
i'd sharpened a set of tools before I went over sick so they handled the very hard wood well.
The final shape was dictated by my trying to keep as much weight as possible while removing most flaws, cracks and holes. When some sort of balance was achieved i then took it through three grades of sandpaper, sawed off the ends, sanded down the turning stub things and gave it a coat of linseed.
It it weighs in a 1lb 10oz compared to its bought sibling at 13oz. I'll give it a day in the linseed tank which will probably add a ounce or so and swell the handle into the head, not that it's going anywhere.
im pretty pleased with it, feels right in my hand.
ATB
Tom