Weighing wood

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What do you want to find out by weighing the wood? Water content?
 
No. I understand MC. In my mind i will weigh my wood after loading a wheel barrow. Might even have a set of scales to do it with. Just curious of those who have scales, or a way to weigh wood.....how they do it.
 
For weighing, I use a small electronic shipping scale (about 12" x 20"). It will weigh up to 440 pounds and is located on the floor just next to the loading door of the firbox. For calculations I use a software spreadheet where the input is temperature readings at storage, 4 locations. I seem to get about 5200 btu's per pound and have adjusted the calculations in the spreadsheet to reflect that including the moisture content on average. The initial numbers needed some adjustment but did not take long to find good numbers. Maybe 3 weeks to get there. Within the same spreadsheet are input cells for indoor and outdoor temps every two hours with a final 24 hour average. My base figures for btu content was based on information from the linked website concerning btu's in firewood:

https://chimneysweeponline.com/howoodbtu.htm

The very first thing is to enter the temp readings of storage to determine that days requirement to get storage back up. Second thing is to weigh out a full or half load and go at it. Third, is to enter other data that I would like to see over time. Forth, if a second loading is required, weigh that amount and continue.

If there is a current demand, I just wing the extra few pounds and most often it is close enough.
 
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I enter top and bottom tank temps along with my current boiler temp into my iPhone. It tells me how much wood to burn to hit my target temp. It also factors in current heat load and hours of burn.

I put 20 to 30 lbs a time on to scale and put in shopping cart until I have what I need for the burn. Then burn whats in the cart.

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I weight wood for moisture content. Most hard wood, oak, locust, red maple is around 35%-40% water. If you take a sample of the splits weight it at the beginning and weight its as it seasons. As it loses 1/4 of its original weight you know it is ready to burn.

I just weight it with a digital scale.
 
Subtract tank top temp from 85, multiply the difference by 2.5 to get pounds to burn. With no load, that gets my tank to 85 top, 81 or so bottom with no idling. When I have a heat load, I repeat the same process just before bed, but by then, my tank top temp is somewhere in the high 70s, so it's 15-20 pounds to top things off.

I have one of those plastic deals for mixing concrete in that I attached some chain to the corners and attach to a luggage scale hanging from the joists in the basement. I can load 100 lbs in it without too much trouble and that is what I burn in my weekly summer burns for dhw.
 
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