Installing the Ring
Now comes the very careful process of installing the ring, with goal #1 being to get it on straight.
I started by dry-fitting everything once more. The top piece was *very* tight sliding into the vertical stab (presumably due to the paint), so I did a bit more sanding of the slot to loosen it up a bit. This actually had no effect, and the insertion of the ring was a bit fraught, but it finally went in OK. The bottom ring was installed as well and I took a look:
The bottom ring piece is just too long. Clearly, the pods ended up a bit lower than spec'ed in the design, for whatever reason. I trimmed the bottom piece down a bit (with scissors) until it looked like this:
Now that is what I'm looking for. In addition to the two ring pieces almost (but not quite) touching, together they appear to form a perfect circle.
At this point I went to glue in the top piece with my SuperGold+, when I discovered that the bottle had completely gone bad. That is a bummer. I didn't have any other medium (gap-filling) CA on hand, so I decided to see if my thin CA would work. To my pleasant surprise it did; I applied a few coats at the seam with the vertical stab, and it looked good. I did where the ring entered the slots in the pods. I only applied the glue on the outside; I couldn't see any easy way to get it on the inside, at least not without some better CA nozzles. Also I'll definitely need some gap-filling glue for the insides. And so, gluing the inside is for future investigation. In the meantime, it's plenty solid with just the outside glued.
Next up: the bottom piece. I fiddled with it and looked at it many times to ensure it was straight, and applied the thin CA fillets as before. After a few coats it seemed very solid. Then, while inspecting it I realized I had never looked at it from the side before gluing...
It's a little hard to see in this picture, but the bottom ring piece is leaning a bit towards the front (left in this picture, and as a bonus it's ever so slightly in front of the top piece. This is a bummer but I'm not going to worry too much about it because this is not an angle that you'll ever be looking at the rocket, and from most other angles it looks fine. Still, it's funny how I just completely forgot to double-check it from the side when aligning it.
And so, the ring is in place. After all my initial hand-wringing about how to make this happen, my plan seems to have worked OK, while my fear about aligning the two pieces also appears to have been well-founded. Unfortunately there really is no obvious way to do it other than eyeball alignment, and it just needs to be done slightly better than I did it. But we move on.