Doug, I may be wrong, but as I understand how those things work (if they're what I think they are) is that you drill the holes for you initial dowels. Slide a dowel into the freshly drilled hole, place one of those pointy little caps on it, then match it up to the piece of wood you want to join to the dowel, give the set up a tap with a mallet. When you pull the two pieces apart, there is a dimple on the piece to be drilled. Supposedly, when you make the drill and insert the dowel, it will match up both pieces of wood.
If, in fact, this is the correct way to use these, I hope you have better luck than I did.
Disclaimer, what I just posted may just be a POS and I may have my head up my butt.
Blake
Yesterday, at a local hardware place, I found this interesting little set of
> General dowel jigs. It's not the clamp-on jig, but a set of little
> coin-shaped things with points, in different sizes. Although I have a clue
> as to how to use them, there's nothing at all on the package itself. The top
> of each piece has a point, as I mentioned, and the bottom appears to
> correlate to the proper drill size for the dowel. Is this correct? Before I
> open the package, is there something better for my purpose?
>
> Specifically, I'm making a step stool. The cross pieces (stretchers?)
> between the sides are dowelled in place.
>
>