Crack is not something I find a safe courting, or even a desirable one. I have assayed its effects in vivo over divided occasions suitable to determine time curves, reinforcing tendency etc. But if I was a crackhead, I would not keep my pipe there of all places. Especially as I use glass vape pieces for smoking the likes of DMT, methamphet, kit, etc. if I am going to vaporize anything I at least know how to build a good pipe from borosilicate glass. But for one, would you really want to put in your mouth, what has been up there? didn't think so. And aside from the propensity for the stems being thin, almost capillary like (I blow them from volumetric pippettes that are past useful, chipped and such, because there is a bulb, connected on the air inlet and inhalation side both, which creates a partial vacuum, when pulled on, burning/charring less compound and allowing the vacuum produced by confinement of the airstream to create a higher vacuum, loaded by cannula and measuring syringe in solvent allows for tiny quantities of highly potent compounds active in the mg range to be dissolved in acetone, a pressurized air stream forced gently through to evaporate it (bearing in mind the quantities are in the range that one would measure with an insulin syringe, only takes better plastic to stand it if acetone be the solvent, methanol works fine, evaporated and deposition of the compound within the evaporation chamber formed from the bulb part)
Wound snap in a heartbeat if treated roughly, but boro glass has a low coefficient of thermal expansion, and it doesn't shatter from heat shock. But the design does work well, and it is an intended feature, the narrowness of the stem, although thinking of improving it by a solid glass spiral-wound around it, so as to allow heating the stem to clear it, and bending it round to act like the bipod of a rifle and the far end as a 'stock', so it can be set down without either rolling or burning a surface. vaping pipes get a LOT hotter than ones for tobacco or ganja/hash.