Okay; finally got around to posting what I did/learned. I really hope somebody finds this useful.
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The first thing I did after actually ordering fur and all was to design the shape. At first I looked for some sort of template, but there wasn't really any good ones out there specifically for a fox tail (Sciex has a good wolf one, though), so I decided to just try and draw one out by eye.
It seemed easiest to divide the tail into four parts: the top (black) and the tip (green) are of course separate, and each is divided into lengthwise halves. I finally decided on a 30" tail with a 7.25" cross section (when flat; when rounded, the diameter becomes ~2/3 of the flat length). I drew that out on a whiteboard:
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Following that, I got out my faux fur and re-sketched the relevant portion of my design onto the reverse side of the black fur. In retrospect, it would have have been better to sketch it on a piece of posterboard, and cut that out so I could trace it twice, but I didn't think of that until after I had cut out the first piece.
At this point, I made a mistake: since the tail was wider on the bottom than on the top, I thought I could be space-efficient with the fur by cutting out the reverse half upside-down. While I was busy playing tetris with my cutouts, I completely forgot that faux fur has a *direction* (the direction the fur points in) and it should match on the both of the length-wise halves. So, now I have an extra, backwards piece of tail laying around
Make sure you keep the direction of your fur consistent on all your pieces!
Once I had two corresponding (and directionally consistant) cuts of black fur, I made a posterboard cutout template for the bottom half (the tip) and traced it out on the green fur. That went quickly and without incident. After I cut them out, I sewed them onto the black halves using my tracing lines as a guide (I cut made my cuts about ~0.3in from my template lines, to provide a nice margin).
Finally, I was able to align the two length-wise halves of the complete tail and pin them together (inside out, so I could use my template lines as sewing guides). I had to use a pencil tube to carefully stuff all the fur inside as best I could before I could sew it. You want all the fur to be facing inward so that when you turn the final product right-side-out, you don't have fur stuck inside.
Once the sewing was complete (this took several days), I pulled the tail inside out again so that the fur was on the outside, and pushed some generic stuffing inside. Apparently, however, the density of stuffing matters - my first attempt left me with a tail that probably could have functioned as a baseball bat (the stuffing was far too densely packed, so it was really stiff and heavy). I pulled the stuffing back out and gently seperated it with my fingers until the density was reduced to an acceptable level. After pushing it back in again, I had to sort of "massage" it around inside the tail until the proportions matched what I was aiming for.
The final consideration was the attachment. I had originally though that using velcro loops would be a great idea, but it turns out that velcro doesn't play nice with faux fur
. At that point, I was pretty tired, so I just purchased some large safety pins and attached them to the top of the tail, then looped my belt through them. I would like to use elastic bands instead at some point, but I haven't purchased any yet.
And that's it! If anybody sees anything that could be improved, feel free to comment.