Fish Fails: my new watercooled Vive sucks
You could call it giving up, but I’m going to call it reaching a conclusion. I know what I would do differently if I were to make a third attempt at a VR face-cooler but I don’t think I have the patience for another go after building my second one. This is the story of where I got with take two, shared in the hopes that someone is inspired to do better. Let’s start with the plan.
I needed to draw this out for myself before I got started. For some reason it was a bit hard to wrap my head around at first. The build is in three layers because I had the “clever” idea of stacking the cooling “tubes” instead of running them side by side. The goal was to present a smooth surface to the face instead of a split one.
I started with a few tests. My primary concern was how to hook up my vinyl air line tubing securely and without leaks. I made a small three-layer bag out of 12-mil polyethylene and used Gorilla Glue to hold the tubing in place. It took a few coats of glue, and 24 hours of waiting, but I ended up with a good proof of concept.
For my second test I switched to the material I wanted to use for the final version, reinforced vinyl. As before, I used various scraps from work, but you could get the same result by harvesting materials from a busted air mattress or even a dollar store beach ball. I welded together a two-layer pillow and left channels opening into the pillow for the tubing. This time I used a vinyl glue to seal the tubes into place. I was pretty proud of my idea to use syringes to draw a vacuum on the pouch and pull the glue deep into the gaps on the side of the tubing where the fabric met. The welds were good, and the glue held back any potential leaks by the tubing. It was time to make the real deal.
I used three different vinyl materials for the final mask. I tested to make sure they welded together first. The bottom layer was the same Velcro-friendly material I used on the original mask. The middle was clear vinyl so I could check alignment of the pieces easier. The top layer was the same as the bottom layer except for being smooth vinyl on both sides. In the photo above you can see my trick for preventing unintentional welding, parchment paper as a layer separator.
Welding the inside was the first step. I used parchment paper folder over the middle layer and worked my way around the outside, reaching into the inside to make the seal. This was pretty fiddly, but it worked. However, it’s when I made a mistake that really took the wind of out my sails. As I was welding, I slipped up and accidentally sealed my water paths all the way across right as I was finishing the inside track. I didn’t have the parchment paper in quite the right spot. That oops meant spending the next hour trying to salvage my work by heating up and delaminating the layers with mixed results. I was able to open it up enough to move forward, though.
Oh yeah, I should probably mention how exactly I’m welding this plastic. It’s a flattening iron wrapped in Teflon tape—a pretty handy trick. I used a potato masher to apply pressure to the top of the iron while welding and it served double duty by also mashing the proto-mask into my work platform, cooling the weld quickly so I could keep working.
Finally, we have the complete picture. At this point I already knew my creation had one too many mistakes to be completely happy with it, but the general plan worked out ok. One of the biggest problems was the unevenness of my welding. The void on the inside is not a consistent size all the way around. I can blame my tools and artistry for that problem. Once I’d hooked up the tubes for a pressure test, though, I found the biggest design flaw.
If you recall back to the original drawing of the design, the middle layer was cut short of the ends so that water could flow around it into the other layers. This worked great in my original test, but the material swap and confines of the mask apparently turned the middle layer into a check valve and essentially no air is able to move between the layers. Bummer. If there was some structure at those points, say some more air line tubing, that wouldn’t be an issue. As things ended up, I think I’ve had my fill of experimenting for now but feel confident this could work with a bit more effort. We’ll see if I want to go another round with it as the summer continues…