cutting borosilicate glass tubes

[adhd-brouwerke]

consulting the hive mind

i'm building some sight glasses for my kettles butt i can't seem te got u nice cut when i'm trying to cut some glass tubes.
i've tryed to cut i with a glass cutter and the tube in a v-block and breaking the tube, grinder with diamond tipped blade, dremmel tool with cutt off wheel, scoring and then heating with a torch and quenching

i cut scorred the tube with a glass cutter butt when you break te tube it isn't a nice cut and croocked so sanded it flat but that took over an hour so i'm looking for a good way to cut it.

this is what i ended up with.

 

[MaxStout]

I have cut thin (i.e., 1/4") borosilicate tubing by notching with the edge of a triangular file and snapping it. No idea how to cut tubing the size you are using. Maybe there is a YouTube video? Anyway, I'm curious to see what you end up doing.

After cutting you can round off the sharp edges by heating the cut ends with a propane torch.

 

[ancientmariner52]

There are glass cutters made specifically for cutting gage glass tubes. No idea what they cost, probably not worth it for a single use. You can try scribing all the way around with a diamond glass cutter, or as MaxStout says, a three cornered file.

Personally, I'd try to find a boiler shop and ask them to cut it.

I seem to remember something about wrapping a piece of copper wire around the desired cut line, leaving a twisted pigtail sticking out. Heat the pigtail, not the glass, with a torch, then quench the whole works in cool water. The cut end should drop off. Then flame polish, as suggested above. Don't quench the hot tube after polishing!

 

[day_trippr]

I've seen folks wrap alcohol-soaked cotton string around the scoring, light it off, and have the waste piece literally fall right off.
Don't think any of them were cutting borosilicate but it might be worth a try...

Cheers!

 

[ancientmariner52]

Just took a quick look on Amazon. Tons of cutters for glass tubing for $10 or so. They look nothing like the internal cutters I've used on gage glasses, but they ought to work.