I had to "Calibrate" those at a paper plant I worked at years ago... you just compared it to the "Control" measure at a certain temperature to make sure it was in tolerance...
Sorry for the hijack...
I had to "Calibrate" those at a paper plant I worked at years ago... you just compared it to the "Control" measure at a certain temperature to make sure it was in tolerance...
Yep, that was the case - I was told by Chapmans (John) when I visited them that the idea was that the handles could be machine-produced to a high standard and that this saved them material (cane) and labour costs over a cane/cork handle - the idea was to remain cost effective as fibre-glass came onto the market. I've fished with a Mk.IV and a 550, I much preferred the 550.