Laser Thermometer

[Alex_Blackwood]

Ah, right. That might knock the idea on the head. What sort of range could I usefully expect? I don't need great accuracy, just the ability to tell whether the stuffing gland is getting unreasonably hot.

From three feet away it will be next to useless.

It may not be accurate but it will indicate a change in temperature so if your gland gets hot it will indicate a rise.