Fuel economy

[bandmiller2]

Anyone know of any studies comparing the economy of bandmills, swing mills and circular mills for the same amount of board feet cut. ?? Frank C.

[Holmes]

That's an interesting thought. I've not heard anything about that, ever.

[Ron Wenrich]

Circle mills often add other support equipment to the power consumption.  On our gen set, we ran a bunch of hydraulics, the circle mill, decks, a vertical edger, a horizontal edger, blowers, conveyors and chippers.  We were getting about 6 gal/Mbf and our time factor was about 45-50 minutes.  That was in short oak.  Put that to black locust and the gal/Mbf goes up as the production goes down.  Put that to long tulip poplar and you can cut those numbers is half. 

There are a lot of factors that go into the numbers that its hard to make an apples to apples comparison.  To me, fuel is just part of the equation.  I can buy all inputs to the equation except time. 

[Chuck White]

With my mill, I usually saw somewhere around 1,500 bf on 5 gallons of gasoline!

So, roughly 300bf/gal!

[dboyt]

By economy, do you mean overall cost (amortization, maintenance, labor, logs, taxes, insurance, etc.) or just fuel?

A lot depends on the design of the mill.  My previous mill used about 20% of its power to keep the hydraulic pressure up, most of which was just lost. A lot also depends on the operation of the mill.  Taking heavy slabs and shutting off the mill when it won't be used for a couple of minutes can squeeze out a few more board feet per gallon.  As Ron says, there is a lot more to getting boards than just the sawmill.

Wood is a far more expensive resource than fuel, and that's what pushed me in the direction of the band saw.  After working with the Portable Sawmill Shoot-Out for a number of years, the band mills  (1/8" kerf) get about 15% over the International 1/4 scale.  That's 8 boards for every 7 cut on a circle mill.

I use less than 3 gallons to mill 1,200 board feet of oak on my manual Norwood sawmill-- but a day's work for me (working solo) is an hour's production on Ron's mill.

[bandmiller2]

Thanks guys, myself I think it would come down to the swinger or the band for strict cost per board foot not including other costs. If production is figured in mayby the circle rig would be in the running. Frank C.

[Brucer]

Over the last 8 years I've averaged 88 BF per litre on an LT40HDG28 (28 HP Kohler gas engine). That's 334 BF per US gallon. At our current (very high) fuel rates that works out to about 1-1/2 cents per BF.

That number could go way higher if I was sawing 12' -8x8's exclusively (with a helper). It could go way down if I was sawing 30' - 8x12's exclusively (with no helper). That's what makes it tough to do a comparison.

[drobertson]

If I did my numbers correctly, the cost for fuel only is .013 cents (avg) per bd/ft.   51 hp, cat, david

[Dave Shepard]

I usually come up with $.017/ft for fuel, bands are the same per foot.

[Nomad]

I usually come up with $.017/ft for fuel, bands are the same per foot.

Those numbers work pretty good for me, if the logs are clean.

[Brucer]

David, I suspect your numbers will work out to .013 dollars per BF. If not, I definitely need to upgrade to a diesel ;D.