This dowel maker makes 3/4" dowels. It has a slitting knife that helps to cut the fibers before the wood interacts with the main cutter.

You could just clamp the cutters in place using chisels or plane irons. But, a permanently mounted blade is more efficient as shown at the end. You'll see me experiment with the clamping method first to check that the concept works, then I mount the permanent cutters at the end.

You'll see me using two different taper or step bits. The one with the wider taper worked better.

Just be patient and tinker with the main cutter and the tapered hole until it works.

I mention in the video that you need to drill a hole slightly larger that your desired diameter. Here, I use a 13/16" bit trying to get to 3/4". The end result was a dowel just proud of 3/4" which was fine for my purposes of making stock in preparation to be used with a trapping plane to make a golf shaft tapering from 3/4" to 1/2" of which you can find info on making a trapping plane on this channel.