# SS Brewtech Volume Markers Way Off

### Help Support Homebrew Talk:

#### slurms

##### Well-Known Member
Looking to see if anyone else has this problem...

I've got the older version of the 10.5 gallon SS Brewtech boil kettle. It has the nice etched volume markers. However, their marker spacing seems to be way off with increasing water volume. Two gallons seems fairly close, and as you fill up and put 8 gallons in, the kettle is reading closer to 9.5-9.75. That's a pretty big difference. Says it's a 10.5 gallon kettle, but it seems that it holds 10 gallons filled to the top.

FYI, I've been measuring water volume by calculating it based on kettle diameter and water height. Ignoring any of the small, constant water displacements (transition from flat bottom to sides, ball valve, and thermometer).

#### rburrelli

##### Well-Known Member
If I were you I would use another way of determining what a gallon actually entails. Use a container and something like a measuring cup to determine exactly what constitutes one gallon. Then add one by one and check markings that way.

#### day_trippr

##### "Feeling much better now, thanks"
I would go with water weight to get the volume additions exact...

Cheers!

#### McKnuckle

##### Supporting Member
HBT Supporter
Weigh your water! 1 kg = 1 L. 3.785 L = 1 gal.

#### day_trippr

##### "Feeling much better now, thanks"
Observe temperature effects, of course. In the "comfortable range" of temperatures water will weigh somewhere between 8.33 and 8.34-something pounds per gallon...

Cheers!

#### Tom R

##### Well-Known Member
The volume markings on my BK are consistently off by about 1/2 gallon.
I made a dip stick by adding one gallon at a time, then marking the stick. A few coats of varnish sealed the stick.

OP

#### slurms

##### Well-Known Member
I originally used a 2qt pitcher I have to fill up and judge based on that. Then I figured, maybe that pitcher is way off. Which lead me to just calculating volume based on diameter and height. Then I finally weighed the pitcher for half the weight of a gallon. It turns out the first time I used the pitcher, and the diameter/height calcs were more or less the same as weighing the water.

My plan is to just use a stainless steel ruler. I know 4cm is one gallon in my kettle now. And just assume a 1.02x factor (roughly) on expansion at 150F and 1.04x at boiling. Close enough! And much closer than guessing based on the kettle markers.

Thanks for the input everyone!

#### Spartan1979

##### Supporting Member
HBT Supporter
Mine are pretty accurate, but I have a BoilCoil in each one so that makes up some of the difference.

#### NathanL85

##### Member
You need to see how the volume markers were made, cold calibrated vs. hot. Water expands when it is heated (specific volume changes) so this does make a difference and the volume markers can be off when cold vs. hot.

OP

#### slurms

##### Well-Known Member
That was my original though for a second, but 5 gallons of the "cold" water (room temp) is showing ~5.5gal on the kettle. Maybe it's calibrated for nearly freezing water? Haha