The above log has been rough notched and is ready for scribing.  Rough notching is a notch cut at each perpendicular intersection that allows the worker to get the bottom of the upper log parallel to the top of the log below.

The scriber is a tool that writes on the surface of the log leaving a road map of the contours of the adjacent log. The distance between the pens, or scriber setting, is adjustable while the ball point of the pens are plumb from one another. Once a log has been rough notched and the remaining gap is as consistent as possible, then the scribe setting is determined by the widest gap, so that the long groove is at least 3" wide at that point.

First cut is approx 3/4 deep, just inside the scribe line.

Next cut is a shallow angle or waste cut. You learn to get comfortable holding the saw in any position, you can see my hand is rotated on the handle so my thumb operates the throttle.

Although out of focus, you can see the angles and depth of the first two cuts.

Once the cuts have been performed from both sides the middle triangle falls out. The remaining needs to be removed. This is a point where I think most all log builders differ, how to clean out long grooves. Some use a chainsaw, a chisel, an axe or adze, a scorp, some make tools specifically for this. I've tried out a chisel and a scorp, with mediocre results. It works but is time and energy consuming. Currently I'm working on a technique where I use a router that is fastened to a sled that guides its distance off the edges. So far it's fast and accurate. Will post more on that later.

Above, a lateral groove finished.

The first step in cutting notches is to score with a chisel, which prevents splintering within the wood that is outside of the notch. Next is to cut just inside the scored line with an angle that is slightly concave, so as to leave the notch concave.

Above is a notch, cleaned out and ready for install. You can see the edge is crisp and smooth, that was the portion scored with a chisel.

Almost three rounds complete. Will be 8 tall total.

Ripping logs

I've chosen the logs for the base round, determined their heights and ripped them flat. Ripping was a two person operation. We used a Stihl MS660 with a helper handle bolted to the tip of the bar. We cut with the top of the bar, so the guy holding the helper handle is getting sprayed with wood chips. Mike said he's been a carpenter for 20 yrs and that night he found wood chips in places he'd never had them.
After ripping they received a once over with a hand-held planer and out to the building yard they went.