I'm pretty handy at fixing all sorts of things - as long as wood is not involved, but I am, without a doubt the world's worst carpenter - bar none. No...there is nothing anyone can do to help me in this area. [ok. i can frame, but forget finishing - of any sorts - too artistic for my brain. if ugly finishing carpentry/woodworking won prizes, i'd have no competition. ok...now, to get serious.]
Yet, I think this one is somethiing I could actually do, especially since pretty doesn't count. I'm not familiar with pool cues, but based on the other Poster's brief description, I've seen similar joinging mechanisms in store bought Coat/Hat trees.
I've actually got some of this hardware in the basement which was taken off of old, broken, now burned as kindling in my coal stove coat tree. I might give this project a go myself. Sounds like fun.
Here's what is running through my mind right now...
1. get the hardware you think that you will need. the local hardware store will have what you want. the male side will be threaded on both ends with a splined divider area/ring. the male threaded part that is screwed into the wood will have a wood thread pitch and cut. the other end of the male piece will have a machine/metal thread pitch and cut. the female end will have a threaded insert to accept the male machine end. the outside of the female will either be a wood thread or fully knurled and/or splined for press fitting (hammering/pounding) into the wood.
2. cut your walking stick at the appropriate length.
3. This is the most crucial and error prone step in this procedure and must be done correctly. Drill holes in each end of the wood which is the same diameter as the central unthreaded portion of wood screw ends of the hardware. This way only the threads cut into the wood and you won't run the risk of cracking your wood or not having enough bite from the threads. If you're still concerned about cracking the wood even from drilling and then screwing in the joining fasterners, then you can wrap your wooden staff with some cloth and bind it tight with some hose clamps (local auto supply store will have them) for extra support when drilling and screwing. This will help if the wood is very hard or old, and you fear that it might crack. Make sure that the holes are deep enough to accept the full wood threaded length OF THE SIDE/HALF OF THE HARDWARE THAT IS TO BE INSERTED INTO THE WOOD. If it is difficult to screw these fasterner halves into the wood, drag the wood threaded ends across an old bar of soap before attempting to screw them in. You'd be better off getting advice on using a carpenters glue or some type of bonding agent on this wood-to-metal interface. I really don't know anything about whether this should be done or not.
Note: About drilling the holes. It is absolutely essential that the holes be drilling "perfectly" vertical for the completed, assembled walking stick to be straight. Find a drill press to do this. A hand drill with one or two leveling bubbles might be used if you're skillful and careful, but it might shift while drilling making the hole on an angle.
One other thing. Since I am so bad at carpentry, I often drill in two, three, or four steps, beginning with a very small bit, and working my way up to the proper size. So, a pilot hole first, at the very least. In this case, I'd go with the drill press, or an end mill with a drill bit. If you know anyone who can work with a table leg, maybe they have the right equipment. This is really way beyond me.
Best bet, take your walking stick to a professional woodworker and ask them to cut it and drill it. They've got the right equipment for "perfectly" vertically drilled holes. You can easily take it from there. Take your joining hardware with you so the woodworker can drill the right diameter and depth holes.
4. thread both the male and female pieces of the fasteners into the wood. Press fit, or carefully hammer the female end in if it is not threaded.
5. now you can simply screw the two pieces together.
6. if there is a gap, then you need to insert (screw, press, pound) one or both of the pieces of the fasterner deeper into the wood. If you have trouble doing this, then the holes need to be drilled deeper. Remove the hardware (only if screwed in) and return to step #3 above. If it's press fit then you might have a problem. In this case, you might have to countersink the male half so that the little portion of the female half that is extending too far can be accepted and you can screw the connection down tight.
Keep in mind that this joint is going to be a weak point in you walking staff, and may be subject to unexpected failure when stressed/loaded during use on steep terrain (the worst time for a failure!!). You may want to bind, for added strength, both ends of the cut wood, near the joint, with some type of band/banding that is more flush than hose clamps.
I'd appreciate any feedback from real carpenters, woodworkers, hobbyists, out there. Please correct any errors, or enhance any deficiencies. I don't want to give bad advice.