We added a short guide to the measuring vacuum section that covers the trapped balloon gauge. The write-up walks through how to size the container, prep the airflow holes, and use the balloon expansion as a quick visual check that a bag has pulled down to around 80% of atmospheric pressure.
If you need a reference while setting up a bag, read the new page here: Trapped Balloon Vacuum Gauge.
The bike-spoke nose clip project page is now published in the lab guide. It documents the parts list, bending sequence, and finishing steps used in the current build.
Read the full guide here: Bike-Spoke Nose Clip Project.
When I talk about how "heavy" a fin feels, what I'm really pointing at is the hydrodynamic resistance the blade builds as it sweeps through the water. The raw feeling is easy to notice, but hard to quantify. To make comparisons across builds, I pulled together a quick benchmark-based model so every fin gets an apples-to-apples resistance score.
The new Predicting Flex page is now live with the tapered cantilever beam calculator embedded on it.
I finally pulled together a quick comparison of what "long" and "short" blades actually mean for bifins. Across the usual depth fin brands there is a pretty clear split between competition-length blades and travel/pool blades.