Past work on band sawmill is here.
Present work (note: present development involves powering the swingblade with a detachable power take-off hydraulic motor from LifeTrac):
Interestingly, with LifeTrac, we can power a hydraulically-driven variant of this device. This will eliminate the engine and 90 degree gear requirements, thereby simplifying the machine greatly. The detachable, hydraulic PTO motor from LifeTrac will be the power source. We know of no other swingblades driven by hydraulics - let us know if you know of any.
This hydraulic variant eliminates engine cost and 90 degree gear cost - reducing prototype cost respectively.
Hydraulic power is defined as Flow x Pressure. The hydraulic power supplied by a pump: P in [bar] and Q in [lit/min] => (P x Q) / 600 [kW]. Ex. Pump delivers 180 [lit/min] and the P equals 250 [bar] => Pump power output = (180 x 250) / 600 = 75 [kW]. 75000W / 745.7 = 100.58hp
LifeTrac has 93 l/min available from the auxiliary hydraulics, and 250 bar - 112x250/600/.746 = about 52 hp.
Our particular PTO motor has 25 hp available, and the following specifications:
According to the calculations above, the power is: 76 [l/min] x 175 [bar] / 600 / .76 = 29 hp. Multiply that by .85 for efficiency and you get 25 hp. Both figures agree.
- Lucas blades, $185
- Peterson - 13-30 hp, 4-8-10" blades - 
Running costs of an 8" blade sawmill per day, from :