Volume calculations

I can't seem to find it.... but I thought someone posted a spreadsheet to determine your volume in inches based on the container size. Anyone have better search foo than I do?

The reason I ask is that I marked off my stir paddle last time I brewed for every gallon I added to my pot, but it is hard to get the line exact using a marker when you are marking up against water. Thought someone may have the calculations.

This also gives me an idea for a sticky.... The "measure stick sticky". If you manage to get a good measurement for your equipment, post the brand and model along with the measurements and where to place the measuring stick. This could save a lot of time considering a lot of these containers are not perfect cylinders Example:

Equipment: Brewer's Best 6.5 gallon ale pale
Placement: Center
Measurements:
1 gallon - 1 1/8"
2 gallon - 2 1/4"
3 gallon - 3 3/8"
4 gallon - 4 1/2"
5 gallon - 5 5/8"
6 gallon - 6 3/4"

Assuming a perfect cylinder, its a pretty easy calculation
Volume = pi * radius^2 * height (times conversion to gallons)
=3.14159265358979323846 * r^2 * height * 0.00432900433
= 0.0135999682004864049730980625318 * r^2 * h

Once you have your radius squared for a given vessel, you can hold the multiplication of that with that huge number as constant and your only variable is height.

For a pot of 16" diameter, you values are
= 0.0135999682004864049730980625318 * 64 * h
= 0.870397964831129918278276001984 * h

Inch...... Gallons
1 ...... 0.870397965
2 ...... 1.74079593
3 ...... 2.611193894
4 ...... 3.481591859
5 ...... 4.351989824
6 ...... 5.222387789
7 ...... 6.092785754
8 ...... 6.963183719
9 ...... 7.833581683
10 ...... 8.703979648
11 ...... 9.574377613
12 ...... 10.44477558
13 ...... 11.31517354
14 ...... 12.18557151
15 ...... 13.05596947
16 ...... 13.92636744
17 ...... 14.7967654
18 ...... 15.66716337
19 ...... 16.53756133
20 ...... 17.4079593
21 ...... 18.27835726
22 ...... 19.14875523





EDIT: I realize it can be very difficult to measure the diameter precisely. Because of this, it might be easier to get a known measurement (such as 5 gallons is 6.3 inches) and work backward.

Once you have that, you can create a spreadsheet for each of your vessels and grab one of these:

http://www.amazon.com/dp/B000I5Z4TE/?tag=skimlinks_replacement-20

If you wanted to get fancy, you could factor in the expansion of liquids at various temperatures also.