Free 3/16 flow meter

[littleTapper]

Can't believe I didn't think of this a long time ago, but whipped up a spreadsheet to help the calculation. Anyone who wants to check the math; please do!

Make two marks a foot apart on the 3/16 tubing, then time how long it takes a bubble to get from one to the other. Luckily almost everyone has a stopwatch available on their phones. Rates are gallons/min and gallons/hour.

https://www.isaacolson.com/web/maple/flowRates.png

[maple flats]

Can't possibly be vary accurate for one reason, the length of the gas bubbles is not a constant, it will vary as temperatures and air pressure vary. it might come close but at best t's just a very rough estimate.
If you want to test the flow on any given day, time how long it takes a container of known size it takes to fill, but realize that will only give you the flow right then, it will usually vary every day, even at different times during the same day.
Just look at the flow, but be careful, it might hypnotize you.

[littleTapper]

Oh, I'm well aware of the limitations and that things change throughout the day. But, it costs very little to do and yes, measuring what's collected will be better. It's just a tool and there can be value in knowing point in time flow rates.