Good news/bad news situation. I’ve managed it, but….
Oaky, firstly, I’ve attached two straps to the ends of my facebow. Clear plastic straps with a few reinforced eyelets. Then I bent the headgear hooks shut (a Leatherman tool is such a handy thing to have!)so that straps cannot be unhooked from the ends of the facebow.
So now you have a facebow with two straps hanging from the end. Attach headgear to facebow as per normal (elastics on my high-pull slips through the hooks even when bent closed to keep the straps locked in place) Bring the loose ends of the straps together behind the neck, and padlock together through the t-piece at the neck of the headgear – ta-dah! Headgear locked in!
Or is it… I’ve discovered no matter how tightly I padlock my facebow in, I can always slip it out of the buccal tubes. And I can slip it out of my mouth. Thus it’s technically “removable”. (Also, if it’s too tight around the head to try and make it “un-removable” it gets really uncomfortable, and then I just want out and all the fun is out of the game – its better for me to have a bit of slack – I want to feel the headgear, not the locks.). However, because the straps are still locked round my neck, and connected to the headgear itself, it still sits round my neck like a collar, and there is this big mass of webbing hanging down my neck. In case no one noticed, headgear inner-bows are sharp, and when tied round the neck it pokes nastily at the throat… so ‘tis easier to just wear the darn thing in the mouth as it was meant to, than it is to remove and wear it round the neck. Which can be a blessing really – the facebow can then be removed for cleaning and eating, but provides enough discomfort to put it back where it belongs when lunchtime is up!
I’ll see if I can take some pics sometime next week to show. I’d call this myth “confirmed”.