Estimating weight of timber.

[mark_goldfinch]

Afternoon all, could any one advise me on how to estimate the weight of a popular trunk. It is approximately 10'6" in circumference and 32' in length, need to estimate for skip allowance on a quote, or could some one point me in the right direction for an equation that might help, much appreciated, mark.

[agrimog]

do a quick volume calc, then refer to one of the many charts that are available on line(googol is wonderfull) bingo quick weight

[morten]

Being from the continent, I have to convert everything to metric units before I can do any calculations (sorry).

 

* 10'6" circumference = 3.2m, giving a diameter of (3.2/pi) = 1.02 m.

* 32' height = 9.75 m

* Fresh poplar density = 600 kg/m3

 

An easy formula for calculating the volume of a cylinder is (height*diameter*diameter*0.78).

 

Total volume, assuming diameter of 1.02 through entire length = 8 m2

As it is likely that the circumference was measured at breast height, I would guess the actual volume to be about 30% less (which would assume a top diameter of 0.7 m) = 5.6 m3

 

In that case, the weight would be 5.6 * 600 kg = 3,360 kg.

Edited May 21, 2014 by morten

[FatherJack]

Here's a very simple Excel spreadhseet that I've used before. Feel free to play and adjust.

Tree Trunk Dimensions 1 etc.xls

[morten]

I found a calculator for you for computing weight of logs: Log Weight Calculator at WOODWEB (imperial)

 

It doesn't have Poplar, but you can use Aspen for similar density.

 

Input:

Species: Aspen, Quaking.

Small End Diameter: 28 inches (my best guess at 70% of large end diameter).

Large End Diameter: 40 inches (your 10'6" circumference divided by 3.14)

Length: 32 ft

 

Resulting estimated weight: 7979 lbs (which is 3620 kg).

 

The metrically inclined can use this calculator: Log Weight Calculator at WOODWEB (metric)

[jomoco]

I got 544kg from the bartlett app for iPads, or 1200 lbs.

 

32 feet at 12 inches dia. Yellow poplar.

 

Jomoco

[se7enthdevil]

I found a calculator for you for computing weight of logs: Log Weight Calculator at WOODWEB (imperial)

 

It doesn't have Poplar, but you can use Aspen for similar density.

 

Input:

Species: Aspen, Quaking.

Small End Diameter: 28 inches (my best guess at 70% of large end diameter).

Large End Diameter: 40 inches (your 10'6" circumference divided by 3.14)

Length: 32 ft

 

Resulting estimated weight: 7979 lbs (which is 3620 kg).

 

The metrically inclined can use this calculator: Log Weight Calculator at WOODWEB (metric)

 

 

good calculator.

 

pity they dont list the species as well as the common name. it's american so sycamore will be "platanus" not "acer".

[morten]

I got 544kg from the bartlett app for iPads, or 1200 lbs.

 

32 feet at 12 inches dia. Yellow poplar.

 

Jomoco

 

The diameter is 40 inches, not 12 inches!

[jomoco]

Oops, yellow poplar at a five foot dia for only 16 feet up weighs in at 12000 lbs or six tons,

 

So yeah could be real heavy pick with a crane.

 

Jomoco

[jomoco]

The diameter is 40 inches, not 12 inches!

 

So I run the yellow poplar app at 40 inches by 32 feet and still get 10,624 lbs or 5.25 tons.

 

That's a heavy log.

 

Thanks for the correction mate.

 

Jomoco