My opinion is DIY Glass Tubes = Bad because:
1) The glass will be unpolished which means that there will be micro-cracks that can cause shattering and further cracking which could lead to glass in the lungs.
2) The glass will not be annealed so it will be susceptible to thermal shock
3) Quartz is overpriced and unnecessary for this purpose. It is also more brittle than borosilicate which could lead to cracking/chipping with normal use and thus glass in the lungs.
4) Cutting glass is hazardous. I can't tell you how many times I have gouged my thumbs and I have even seen people (yes, more than one) pass out from loss of blood after doing the same with the score/cut method. I have also seen a few people go to the hospital for stitches. It takes practice, and why do it yourself when I am here offering to do it for you?
Pyrex is a brand name of borosilicate glass. I currently have a borosilicate teapot, which I use on the stove without problems. Chemists all over the world use borosilicate glass for boiling water and other chemicals. It should be able to withstand the heat.
Kami has ordered and will be sending me a whole bunch of borosilicate glass for this wick application. I will be cutting it all, polishing it all, and annealing it all free of charge for her. There will be WAY more glass here than any one person could use, so I assume she wants to share...Kami?
If that's the case I will be sending them out "Buddy Tip Style" for free on TrippyTips.com after sending Kami back however much she wants. I think this is a really cool project. In fact, this project is what caused me to join ECF way back when, and I am still willing to contribute my effort/skill to it, but I want to see it done right.