Its amazing how you find things to waste your time when you're retired. Following yesterday's attempt at a canal calculator disc, I've come up with Mark II and a new name.
Here's a close up view in case the main view is too small.
Red underlining of the lock name shows there is a reasonable pub nearby. The main difference form yesterday's model is that the time scale has moved to the inner disc, and the places (all locks in this case) have moved to the outer. Following an idea from Halfie (thanks) I've used a standard 24 hour inner disc. Rotating this inner disc gives times between any two places.
I used an average cruising speed of 3mph and allowed 15 mins per lock. Everyone knows that won't always be right, but past experience shows it averages out tolerably well.