Not as far as I know. Practically speaking there are several disadvantages–the slots limit the light on the markings, parallax effects can mess with the reading, it requires two full surfaces sliding against each other which increases friction, etc. Plus with a regular vernier scale you can see both sides of a line, which could give you a better sense of how they line up (“vernier acuity”). But in a case like this, where precision isn’t a top priority and ease of use might outrank it, I think there’s an argument to be made for it.

I wouldn’t have caught that the gallery link was wrong if you hadn’t mentioned not knowing how the tool was used, so thank you as well!

Yeah, it’s definitely not the most precise thing. It’s good to around ±1mm. I tried to measure 1.75mm filament with it, and it just reads 1, not even between 1 and 2, so for critical measurements the physical matches are definitely better.

And yeah, here the vernier effect is not giving very high precision; it’s just giving a way to space the marks out enough to be printable, but indicate movements that are as small as a printed line.

Vernier calipers are absolutely ingenious, and it’s a shame that more people don’t know how to use them.

Sorry, just realized I also had the wrong link for the gallery that included photos of the tool in use! I edited the post, but here’s the corrected version of that: https://imgur.com/gallery/moire-vernier-radius-gauge-design-3d-printing-ajy0GBg

Sorry all! I meant to post a video of the moire/vernier effect in action, which is the most eye-catching part of the whole project, as the main image for the post, but it didn’t upload. And now when I try to edit in a link, or post a link to it in the comments, it’s telling me “blocked URL.” But there’s a link on the printables page, and the version with the older version is in the imgur gallery which is linked.