Control Design
Automation of the cutting operation utilizes linear actuators for adjusting each cutter at the press of a button. Firgelli Bullet .50 Linear Actuators were chosen because of their capability of moving 1124 pounds (5,000N) at a 0.08 in/sec and being easier to maintain than similar hydraulics. the need for hydraulics. Each actuator is controlled by FCB-1 Control Boards with touch-screen displays allowing for feedback of greater than 1/16" precision in this application.
Fully assembled control cabinet testing prior to install.
Power is supplied to the control cabinet via 120v mains power and is transformed to 12V DC 25A output for the controllers. The actuators are moved in and out by rocker switches mounted to the outside of the cabinet. These are each wired to fuse to protect the actuators in the event of a mechanical jam. While the power supply and the control hardware have internal fuses with higher ratings, they have a higher current failure rating. Externalizing the fuses allows for easier maintenance and trouble shooting.
Control cabinet wiring diagram.
Mounting Actuators
The trailer jacks used to adjust the cutting heads previously were removed. The actuator brackets were welded in their place and the actuators installed. The two 12" stroke actuators mounted underneath the rough cut motor sleds, while the 18" stroke was attached to the planar housing.
Trolley Solidworks model illustrating actuator placement.
Bottom view of the rough cut motor sled with actuator installed.
Wiring and Cabinet Installation
Each actuator's wiring harness is routed to a weathertight junction box attached to the trolley. Threaded holes are used to bolt the junction box in place.
Each actuator is wrapped in a color coded electrical tape, with matching tape on each wire run along the festoon. The festoon runs the length of the lathe and back into the nearby operator's shed.
Weathertight junction box with wiring for each actuator.
The cabinet is secured in the operator's shed with the addition of a fused mains power disconnect. This ensures the control cabinet can be opened safely.
With the wiring complete the actuators are calibrated to the minimum diameter log. The lathe is now ready for operation.
Finished control cabinet installation with fused disconnect.
Operation
With the installation complete, the lathe returns to service.
Turn the volume down before playing this video. The lathe is very loud during operation.
