How Much Sawdust Will I Make?

Formulas and rules of thumb for estimating volume of sawdust generated in bandmill operations. September 5, 2011

Question
I'm waiting for delivery of a new Timberking1220. I've got the place it goes leveled off, but now it has 1' of new snow on it. Good thing I laid down a tarp.

Anyway, my question is how much sawdust should I expect to get from this per 1000 BF of plank or 4/4, and what are you guys doing with sawdust? Should I save and try and resell?

Forum Responses
(Sawing and Drying Forum)
From contributor S:
I operated a small lumber business for many years and my sawdust extraction equipment was a grain scoop shovel and a big contractor's wheelbarrow.

I graduated to self dumping hoppers, still loaded by hand. Get a farm tractor with bucket and scrape it up and dump it in a pile. I gave away sawdust to people who used it for livestock bedding. I told them they could have it for free, but I wasn't going to load it. I always got rid of it.

You might be able to sell sawdust in your area, but you'll have to spend time loading it. Throw any walnut sawdust on the burn pile or over the bank and bury it.



From contributor R:
Ditto to everything above. You'll get about 2 big wheelbarrow loads from 1000' of 4/4.


From Professor Gene Wengert, forum technical advisor:
You can figure the amount of sawdust by multiplying the kerf (width of cut by the blade in inches) times 1000 (for 1000 BF) and then dividing by 12 (to convert inches to feet) and then multiplying by 1.2 (as there are two sides to about 20% of the pieces that do not have lumber adjacent (that is, have a slab)). This will give you the cubic feet. You can also multiply by 1.2 (adding 20% more for sawdust coming from the edging and trimming process). You will find that sawdust is only about half as dense as solid wood... so 1 cubic foot of wood converted to sawdust is about 2 cubic feet of dust, so double the number.

Example: [3/32" kerf x 1000 / 12] x 1.2 x 1.2] = 11 cu ft. And then x 2 = 22 cubic feet.

Another estimate is that 6% of the log's volume will be sawdust with 3/32" kerf.

Note that you will likely have more volume of slabs (a slab is the rounded piece that is first cut off the face of the log and is not big enough for lumber), edging strips and end trim... perhaps 30% of the log's volume. Disposal of this material (usually firewood in a small operation, but chips in a larger mill) will be important.