To recap the past few work sessions: I tried to re-open the channels on my lap by warming the pitch and pressing a steel ruler into the existing channels. This caused the edges of the facets to mushroom up, so I tried a warm press to fix things. This was overdone (too hot, too much pressure, left for too long) so that I ended up with a perfectly smooth featureless lap. I then tried fixing it by cutting channels in with a craft knife, but my knife-fu was weak and I ended up chipping great divots out of the surface. So I tried the warm press - steel ruler combination again, this time paying more careful attention to the variables, and ended up with a normal-looking lap again. I put in an hour's polishing, during which the lap behaved like it was brand new: Sticking, skipping, and generally misbehaving.
Last night I returned to regular procedure: Cold press, with a thick layer of cerium oxide slurry, followed by 1/3 MOT W-strokes. That lap finally seems to be fixed again. I only put in a half hour's polishing, and did not examine the surface to see my progress - I assume that it hasn't changed much since last time - a few cm's near the edge still remaining to polish out.
On a different topic, the family and I have been looking to own a home for a number of years but have struggled to find something that's big enough, to our taste, in a suitable area, and within our budget. So now we're looking for vacant land and planning to build. Yesterday we visited a property that's a lot further out from the city that we'd previously considered. Virgin land, proper African savannah, and if you pay attention to the ground you see many different species of plant woven through the grass. And it's quiet. And it will be properly dark. So if we buy it, expect a new series of stories in this blog about the construction of my observatory!