Well I'm truly impressed with this spreadsheet though a little depressed by it too - it's so professional.
I have a suggestion. I've found it useful to included two extra columns that give the distance from the hour point to the centre and to the noon point. Then you can use a very simple method of construction. Put a peg in the centre and noon points and attach one of those retractable steel tape measures to each peg. (A loop of string round bamboo pegs works well). Then you retract or extend the two rules, one in each hand, with them crossed over in front of you while someone reads out the distances. All the hour points can be very quickly marked this way. Cheers, Richard -
