Slab Mill

Rollin Bicskei and Travis Haley

Problem Statement

Design and build a mill that will auto-matically cut junk slabs to standard firewood lengths.

Background

• After the client is done processing logs in to lumber there are leftover slabs unfit for standard use.

• Instead of wasting the wood it can be processed in to firewood.

Specifications

• PTO shaft driven, 550rpm, 34hp• Hydraulically powered drive units• 12-24” cuts off of 16’ slabs• Maximum width of slabs 20”• Manually loaded slabs• Portable, most likely on a trailer

System Diagram

Conveyor

Adjustable Stop

Saw Blade

Gap between conveyors

Conveyor

Roger Howes

Wood SlabsClamp

1

2

3&45

6

7

Electrical System DiagramPLC Cut Length

Selection Buttons

Slab Fully Advanced?

Sensor

Mechanical Stop Pos. Sensors

Clamp Pos. Sensors

Saw Vert. Pos. SensorsConveyor Motor

Valve

Worm Gear Motor (Horizontal Positioning)

Chainsaw Motor (for motion) Valve

Chainsaw Valve

Mech. Stop Motor (Vertical

Positioning)

Sensors (Input)

Mechanisms(Output)

Hydraulic System Schematic

Mechanical Stop

Conveyor

Cutting Mechanism

Mechanical Stop State Diagram

Raise

stop

Stop- right

Pause

16”

20”

24”

Lower

Stop

To conveyor S.R.

State

stop==up

Stop==right

lengthsel.==24”

lengthsel.==20”

lengthsel.==16”

dist==16”

dist==20”

dist==24”

stop==down

raise stop

lower stop move left

move right

Pause

lengthsel.==dist

lengthsel.!= dist

Conveyor State Diagram

pause

Conv-eyor off

Conv-eyor on

From mech. Stop routine

To clamp routine

stop==down

stop sensor == 1conveyor != on

State

Conveyor Status

Clamp State Diagram

Pause

Raise clam

p

Lower

clamp

To saw routine

From saw routine

To stop routine

conveyor==off

clamp==down

From conveyor routine

clamp==up

State

raise clamp lower clamp

Saw System Diagram

State

raise saw lower saw

Pause

Cut-ting

Raise

Saw

to clamp routine

from clamp routine

clamp==down

saw==through

saw==up