Equipment Calibration

Hey all.
It's been a while since my last post, I'm more of a reader than a poster, but this weekend something happened that I thought I would pass on and hopefully save someone else some headaches.

I bought a new fermenter (plastic bucket type) and it had the gallons marked on the side. After brewing up a Pils and pouring it into the new fermenter I noticed how far off the marks where.

Here's the headache part I used a plastic koolaid pitcher to fill all my old equipment and mark the fill lines. It wouldn't be so bad but it looks to be about 1/2 gallon off at the 5 gallon mark. That probable explains why I was always tweaking my software to get the numbers to match and why I only get about 38 beers per batch.

I used a measuring cup to check the koolaid pitcher and it was off so I used the wife's other measuring cup to check it and I got another all together different result. (Everything is off.)

So after a little Google searching I discovered that a gallon of water weighs 8.34 pounds.

Where I work at we have to have ISO certified scales for weighing, so I'm going to bring home one of their 5 pound weights today to check my scales and then mark my koolaid pitcher after weighing out 8.34 pounds of water.

You would of thought I would of learned my lesson after earlier in the year I discovered my Wally World thermometer was off by 7 degrees.

I just might become a brewmaster yet.

So is there anything else I should be checking?

I am wondering if the difference you are seeing may also be, somewhat, attributed to temp difference between the "calibration" water and your final water. I wouldn't expect the difference to be as dramatic as you state tho'.

At boiling there is an average of 4% volume increase due to expansion. I doubt you are putting boiling water in your buckets but...........

After checking and double checking I was off one cup per gallon which was 2-1/2 quarts per 5 gallon batch. That's a lot.

My scale for grain was only off about an oz at the 10 pound mark.

It pays to start with the basics.

Spending enough time in a lab I've learn not to trust any equipment.