This came about after realizing that somehow, the original skid stoppers I had gotten with my Align 550 had fallen out. Apparently, I stuck them in and didn't glue them in very well, and during the course of flights and transport, I ended up missing a few of them.
Well, when I looked up just buying the stoppers, NOBODY (and I mean NOBODY) sells JUST the little plastic stoppers - the only way to get them is to buy an entire set of skids, which wasn't worth it JUST for these little caps.
So, I busted out the calipers, measured it out as best I could, and mocked these up in Onshape.
I printed this in PLA, but you can print them in PETG, or, if you think they'll come out better, try them in TPU - the rubber might help them grip the inside of the skids better. (I haven't tried it yet, but it might work out ok)
This was printed at 0.2mm, and you WILL need supports for the lip and a brim of at least 3 lines, or else it won't print properly. I know it doesn't seem like the supports would be needed, but I found it was necessary or else the stopper didn't seat properly on the skid. They do fit a little loosely in the skids, but a little bit of hot glue or thick CA glue (you can try some thin CA, but that might not be enough and might just run) around the end of the stopper, and you should be good to go!
The author marked this model as their own original creation.