Excellent tool for quickly cutting holes in steel. The only problem with this and other rotary power cutters is that after the tool has been used, the heat and pressure of the process causes the cutter to be very tight against the mandrel. You then need to use a vise to loosen the cutter. Well, they crack if you squeeze them too hard. The cutters require flat surfaces to seat the mandrel wrench.
If you're drilling holes and have used traditional hole saws, make the switch now, unless you're drilling holes in wood that don't require neatly finished edges. For holes in aluminum and plastics like acrylic and polycarbonate and other manufacturing applications, this is the cat's meow. After 30 years of using traditional hole saws and drill bits I can't say enough about them or regret not finding them 3 decades ago. Now we have small and large sets.
The thread is screwed on but there are no key points on it, just a nut that goes behind and rubs on it. Adjusting the torch taut by hand seems normal, but be sure to slowly increase the cutting pressure. I suspect the cutter was a bit loose and when it touched the material it immediately crossed the cutter onto the shaft. No amount of force will remove it (I'm talking about the force of a pipe wrench) and emailing Blair didn't help as they don't guarantee it, so now the kit is useless to us…