Great work peeps
I do give myself a lot of leeway on allowable materials considering history. Brass bowls, aluminum tokers, and beer can bongs. I've eaten out of pitted aluminum pan throughout my entire youth. What's going to kill me now has long been established in my system. However, I have to say that the frequency of use is different today so daily drivers must be safe. Short of vaping arsenic directly, I find my neighbors are killing me faster than my little DIY treks. I will make clear however that I in no way wish to subject anyone else to these hair brained ideas without full disclosure. No less than what I have a right to expect from any of you.
Having said all that, I looked for 8mm or 5/16" ID stainless tubing with a wall of say ~.005". Not to be found on the general market but that is what I would need to make things 'special'.
As to alumina, pretty simple stuff. It is a grainy substrate that is normally vacuum tight. There are 2 ways to buy it; fully cintered or bisque. Bisque is soft and machines like chalk. You fire the bisque at some insane temp and you get a hard stem roughly equivalent to B-glass and better as noted on thin elements. There are 2 ways to fabricate alumina; you can machine the bisque for rough dimensions and do post-fire work with diamond grinding. Many shops elect to fully hard grind short runs.
Today, you can buy ready-to-use 8mm ID and 12mm OD 100mm long alumina tubes from eBay. The reason I say these are inert is that they come to you after having gone through a 3,000F furnace. There is absolutely nothing going to off-gas from a fully fired alumina part even if you put a torch to it. This is the primary material they use for ceramic heaters. The only thing you might do if you want to make sure all process materials are gone (like oils from hands or dust from surfaces) and washing is not sufficient for your constitution - take the flame torch from the garage and set it ablaze. You can't hurt alumina with heat unless you have the professional equipment.
I am considering making my 'glass' stem using an alumina tube. I like the fact that these mostly opaque stems hide/obscure the messiness inside the stem and is still a usable element in design. I do like the fact that alumina is completely inert and doesn't sluff off alumina dust.
From eBay, the 12x8x100 tubes are ready to use, I also found a thin-wall 7x5x100 that would follow my fabrication convention perfectly. These run under $15 if anyone is interest. I'm talking myself into one today.
Where I was going with a haughty multi-hundred dollar ceramic stem for George
@VapCap would look something like this:
That stem just felt 'right'... but that was the first time I vaped flowering Quince. Not bad I must say. No buzz though.
Didn't I warn you all that my VAS is expressed in DIY?