DIY volume gauge

I have been having a hell of a time with getting accurate volumes. What I have been doing so far has been good enough, but I'm always seeking ways to improve my process and I feel accurate volume measurements will help me do that. I'm not much of a craftsman, so to keep this as simple as possible, I was thinking maybe I could buy a pressure gauge and attach it near the bottom of my kettle. Then all I would need to do is replace the pressure scale with a blank circle of paper and mark off increments as I pour in known volumes of water. Pretty straightforward, but just wanted to see if anyone could see any inherent flaws in this idea. Thanks.

The difficulty is getting a gauge with a range of 0 to 15 inches of water, which is 0 to .5psi.

Interested in ideas also

Sight glass is the only way I can figure and it's pretty simple too.

measuring mass would be the most feasible solution.

But honestly, how far off is your sight glass? are you trying to measure down the the mL?

As long as your within a few hundred mL you should be fine, i mean, when you extract from the fermenter, what kind of measurement device would you use there?

It sounds to me like the OP was looking to use a pressure gauge. Every inch of liquid in the vessel would add .03 PSI to the gauge. I haven't seen anything with that kind of sensitivity in a mechanical gauge.

Stop nuking it out!! I'm assuming you're on one of the boats in Pearl and I just had to say that after seeing your name! Just go with a Bobby M Sightglass, calibrate it using a one gallon water jug and mark off the increments and you will get a pretty accurate readout.

I saw on here some one is using a load cell. After seeing that i use my shipping scale under my mash tun.

I use a stick with "self-calibrated" markings at specific volumes. Cost = $0.00

rcsoccer said:

I use a stick with "self-calibrated" markings at specific volumes. Cost = $0.00

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I do the same using the spear of an old keg I converted to a keggle, just didn't know if there was a better way

What Im thinking of doing in the future is using a force guage under the kettles. Ill know and zero out the weight and be able to know the amount of water based on weight and density. The problem that will arise is for the boil volume, the density of the wort will be different for each batch, so figuring it out would be the problem for the boil volume, but for mash volume and sparge volumes it would be simple.

The problem that will arise is for the boil volume, the density of the wort will be different for each batch, so figuring it out would be the problem for the boil volume, but for mash volume and sparge volumes it would be simple.

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Well, in theory the definition of specific gravity is just the ratio of the density of the wort to the density of water, so if you take a preboil gravity reading you just need to multiply/divide by the gravity to convert back and forth, but how this would vary with temperature might get tricky.

Thats what I was thinking also

Although, now that I think about it a little, you don't necessarily need a pre-boil volume. At the end of the day, you want say 5Gal of wort with a certain gravity, so from that you can calculate what the final post-boil weight should be. If you know your evaporation rate, you can convert that back to water weight that gets lost during the boil, so from that you can figure out what your target pre-boil weight should be (which is then independent of temperature).

The only catch here is if you miss your target gravities you'll have to correct, but if you add enough water to hit you pre-boil weight and then take a pre-boil gravity reading you should be about to see if you're off.

Although, now that I think about it a little, you don't necessarily need a pre-boil volume. At the end of the day, you want say 5Gal of wort with a certain gravity, so from that you can calculate what the final post-boil weight should be. If you know your evaporation rate, you can convert that back to water weight that gets lost during the boil, so from that you can figure out what your target pre-boil weight should be (which is then independent of temperature).

The only catch here is if you miss your target gravities you'll have to correct, but if you add enough water to hit you pre-boil weight and then take a pre-boil gravity reading you should be about to see if you're off.

Pretty much what I was thinking of doing, for example my system is going to be a Brutus 20 electric (controlled by an Arduino/Android): Here would be the steps in theory:

1. Pre mash water volume in MT - calculated based on force gauge and known density of water, zero out the weight of the equipment (use water value for recipe based on calculations from beersmith or however)
2. Sparge water volume in BK - calculated same as MT and the amount via a program or however
3. After mash and recirc and all wort is transfered to BK measure SG, based on SG can find density and get preboil volume from force guage and calculations.
4. Adjust water volume as needed to get desired volume if low, this is again easy, you know the current weight and can figure out how much water to add to get desired volume
5. Post boil volume, same as pre boil can take SG reading and with the weight know the volume.

Here are the problems I see with this technique: If you are wanting to boil off to a specific volume would need to know the starting volume and SG and could only calculate a theoretical final SG based on a boil off calculator and then could find a theoretical weight. This can be useful to know in cases where your brewing environment changes, for example, outside humidity and temp changes. You could tell if your boil off rate is too vigorous and need to lower heat or cover to adjust.

Another option Ive been looking at incorporating into my build is a differential pressure guage:

Following this guide HERE

It would use on of these and have a tube go into a tee right before the ball valve.

That is very cool. Is it sensitive enough for the tiny, tiny pressure change?

Havent got it yet, working on ideas for how I want to monitor and measure volumes, though there are several people using this already. Also brewtroller website sells them so Im guessing it is enough for our uses