I live in michigan, and like any good descendant of french canadians I love maple syrup. Starting in 2012 I began experimenting with making my own syrup.
I typically collect the sap with re-useable stainless-steel health spiles (health spiles have a smaller 3/8" diameter than a traditional 7/16 spile.) from http://www.rmgmaple.com/. Depending on the location, I'll either use 1-gallon milk jugs (I buy empty purified water jugs from the grocery store) or 5 gallon buckets.
To boil the sap (which must be reduced 40:1 to become syrup), I use a stainless steel half-barrel keg with the top cut open set inside a 55 gallon drum with a cast iron propane burner modified for natural gas (mostly this involves drilling a larger orifice into the bronze fitting).
Maple sap only flows when the weather is below freezing at night and ideally above 40°F
There may be less than a dozen days of high sap flow in an entire season, so tapping at the right time is critical, if trees are tapped to early, the tapholes will heal before the season ends. It trees are tapped to late, the prime sap flows will be missed (the earliest sap flows are the sweetest, later sap flows become bitter and lacking in sugar)
To help decide when to tap the trees, it is extremely helpful to be able to see a plot of daily temperature fluctuations at your sugarbush. To help with this I've written a python script that pulls hourly temperature data from wunderground's API and charts them with some helper coloration so that it's easy to identify when temperatures are beginning to fluctuate in the right range.
The source code is available on github
Check out a chart generated from Jan 2014 - May 2014. Notice that the ideal tapping time starts near the end of march. If the trees had been tapped at the beginning of march, some sap would have been harvested, but the tapholes would have healed too quickly.