Henry, when I saw your photo of your blower tool, I had to laugh because I had just thought of building something like that myself. My wife and I joke that when I dream up something clever, it “magically” appears somewhere on the web.
I haven’t built a thing. My idea was to create a small, acrylic box (because they are easy to glue and you can see through them and cut and glue a silicon gasket for the seal (because I have silicon casting material). I would have to make sure to use the right kind of glue to attach silicon to acrylic.
It’s nice to hear that you have yours working. Wouldn’t it be nice if someone would sell something like this?