TAIL CONE
The tail cone shroud is pretty straightforward, as far as shrouds go. BT55 to BT60, 1.25" long. But it will have fins mounted on it, which adds an extra wrinkle or two. Also, *every* shroud I make is a technique exploration where I try to get better at it for the future. Apologies I didn't take enough pictures on this one to really show everything I did. More detail on request.
Since this one will have fins on it, I needed fin placement marks, which are surprisingly hard to add yourself after-the-fact. After an
endless amount of fussing, I finally got my Perl installation fully working on my laptop so I was able to use my custom shroud generator to create this template, which is more of an adventure in trigonometry than you might think:
I wish I had had this script when I did Diamond Cutter; getting precise placement of the canards onto the forward transition was quite difficult (and I did not succeed TBH).
Anyway, I made the first shroud on 110 lb cardstock normally. I put the tab on the top of the template shown above, so the top fin line was "below" the other end of the paper. Then I cut out a second template to go on the inside, and here's where my technique deviates from typical practice. I do not form a second complete shroud, because I when I do this I always end up with bulges where the seam is on both the inner and outer shrouds. Instead, I cut off a piece from one end of the template about the size of the overlap tap on the outer shroud. Then I glue it in place like so:
Things to note here (click to enlarge):
- One end of the inner shroud just about butts up against the glue tab on the outer shroud. Normally I want to get it touching, but I didn't quite hit the mark here. Close enough.
- The other end comes just about to where the seam is on the outer shroud (not visible in above picture).
- The inner shroud is still offset a bit from the narrow end of the outer shroud. If this were not true than the inner diameter of the shroud would be too small.
When glued like this, there is (almost) exactly two layers of paper around the entire shroud. There are *no* spots where there is an extra layer that will tend to bulge. Also, there is never a problem where the inner shroud is not *quite* the same shape as the outer, and they don't glue perfectly surface-to-surface. The inner shroud conforms perfectly to the outer. Downside is there is a *slight* weak spot in that gap between the inner shroud and the outer glue tab. It also is very difficult to do this on long skinny shrouds (will explore this further in a future build). Frankly it is a bit tricky to pull off just in general, but I really like the results.
Finally after the glue is totally dry the extra is trimmed off the large end and here's the finished piece:
Final notes:
- I *always* set my shrouds on a body tube and centering ring to keep both ends in perfect round while drying. And usually I store them that way (if necessary) until it's time to use them. That is why the shroud looks so perfect in the above pictures.
- This finished shroud is almost certainly stronger than it needs to be. I have no problem with that.
An there is Too Much Writing About A Paper Shroud. You're welcome!
(Seriously though: do folks actually want to read this much about little stuff like this?)