At least with my Ilford thermometer I can get the temperature right. Thought it's going to take a bit of trial and error with regard to how long the 1 litre of ID11 and 500ml of fixer need to be in the University's Hall of Residence freezer to bring them down from room temperature of 75F to the optimum of 68F. (Though, incidentally, the Ilford thermometer has 65F marked in red, as if that was the optimum... Perhaps it was in pre-central heating times. It's pure social history, this retro photography lark.)
[EDIT 9.30PM: I made a right arse of that. The roll stopped winding on, and in in the confined space of a halls of residence wardrobe, I was getting very hot and stressed. I thought I had most of the roll on, and it wouldn't hurt to sacrifice a few frames from the end...
So I snipped it off. Which was a blunder because only the first ten or so exposures were wound on, and I lost most of the film when I opened the wardrobe door. Bastardo! The roll's hanging up to dry now, and it looks as if there'll be three or four exposures that are ok. Which is piss poor out of 36 exposure roll.
I went through my collection of unexposed film and I've got a roll of Kodak TMax. It will be sacrificed to the Gods of Film Dev later as I play around with the dev tank's spool to see where the hell I went wrong.]