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Question: : What measuring equipment do you use for brewing?

Answer: If you're a "freestyle" brewer, careful measuring is not particularly important. However, if you're trying to use someone else's recipe, brew to style, or especially if you're trying to reproduce one of your earlier award-winning beers, then careful measurements are critical. Accurate measurements of weight, volume, temperature, bittering and gravity will let you hit your targets and brew great beer time and time again.
With a typical brewing session, weight is the first factor you have to consider. If you don't hit your starting weights, you'll miss your gravity or bittering. Fortunately, you can use the scales at the shop for this. I use the big floor scale to weigh out my base malt and any specialty malt that uses more than a pound. Make sure you tare the bucket before you start. Then, try to hit the mark as close as the scale will read. For small amounts of specialty grain and for the hops, I use the Pelouze scale. Be especially careful with the hops, since the 0.1 ounce resolution is just barely good enough. And don't forget to note the alpha acid level.
Once you get home, there are some more measurements you have to do. The first usually is measuring out brewing water. I find that the easiest way is to use the volume marks on the inside of the "Gatorade" cooler. Some of the stainless steel boiling pots have volume marks too. Remember that if you are draining from the Gatorade cooler that you won't get the last bit of water. I fill it up an extra gallon and stop when it gets to the bottom mark.
Next on the list comes temperature. I found that the fat floating thermometers from the brewshop are too slow to respond to be useful for mashing. Instead, I use the long-stemmed dial thermometer. Also, I have a digital thermometer from Taylor for fine-tuning. It reads to 0.1°F and responds quite quickly. However, the electronics are sensitive to moisture. I've had to replace it twice so far. As I've mentioned before, the mash temperature is the most critical. The temperature of the sparge water and any later measurements are far less exacting. If you have one of those fat floating thermometers, throw it into the sparge water, rather than the mash. It should have plenty of time to respond.
For some water sources, you'll need to adjust the pH. An electronic pH meter works well, but it is expensive and needs to be calibrated each time. pH papers are easier to use and are much cheaper. An even easier method is to add some gypsum (calcium sulfate) to the sparge water. This works well for any high-sulfate beer, including most English styles. The pH is self-regulating, so all you have to do is throw in a rounded teaspoon per five-gallon batch. Stir thoroughly, since it dissolves slowly. For low-sulfate styles, I use 10% phosphoric acid. But be careful: this stuff is strong and you can over-do it unless you check with pH papers.
Next comes bittering calculations. Assuming you got your initial weights and alpha acid correct, bittering is determined by time. Fortunately, just about any clock will do. If you like to RDWHAH a lot during your brew sessions, you might want to get a timer. (Remember, a ding is better than a Doh!) Also, keep your boiling and finishing hops straight, since they usually have different alpha acid levels. The timing on the flavoring hops is the most critical, since the rate of bitterness extraction is at a maximum when you shut off the heat.
Next comes the starting gravity. You'll need to buy a hydrometer from the brewshop for this. Assuming your mashing extract efficiency is good, the gravity will be at the target when you get the fermenter up to its "full" mark. What, you don't have a "full" mark? Go back and fill your fermenter up with a known volume of water from your Gatorade cooler. Then put a mark there with a waterproof marker. Now, if your wort volume is low, check the gravity. (Don't forget to make that temperature correction.) If the gravity is a bit high, then top up the level. Stir the wort thoroughly and then take another gravity reading. If the gravity is already at the target, leave the level alone.
The last measurement you'll need to do is the priming sugar measurement. Most recipes call for ¾ cup per 5-gallon batch. Rather than use volume, I usually weigh out the amount, using the Pelouze scale. I use 4.4 ounces for a medium-carbonation beer.
Finally, don't forget to take notes. The most accurate measurement in the world does no good if you can't remember what you did. Notes are most important when you miss your targets. Keep track of them, and you can fine-tune things like your mash temperature, mashing efficiency, and bittering estimates. If you brew using a reproducible technique, you'll find these come out the same time after time.