Sawmill Design

Overview
Design

Design
Z Height Leveling
 * Turnbuckle attached to upper z adjustment peg

Evenness of Z Height Raising Along 4 Posts
 * Build 4 inch winch drum - each revolution winds 1' of wire

Log Taper Adjustment
 * Disconnect mechanism for connecting rod between front and rear z-risers to create a height differential between the two ends of the log

Edger
 * Adjustable from 1-3 blades in standard version, up to 6 for 6 2x2 lumbers in one pass
 * In 3-blade configuration, top edger blade is controlled by a crank that can be adjusted while sawmill is running

Gantry
 * Box truss design

Carriage'
 * Clearance of 1/8" around gantry

Hydraulic Hoses
 * 4 Hoses
 * Mast at either end

Trailer Hitch
 * Telescoping piece of tubing in frame
 * Hitch retracts for sawmill operation

General
 * Counterweight for hydraulic motor on one side of gantry - balancing
 * Saw and collar - typically from same manufacturer

Vertical Motion
 * One crank with a worm gear controls one side, connected to second side via connecting rod
 * Vertical adjustment - 4 worm gear sets -
 * Bronze bushings - for vertical adjustments

Horizontal Motion - Crosswise
 * Crank with indicator
 * Sprocket with chain to another sprocket with pinion, riding on rack
 * Rack faces down
 * Sprocket and pinion sheltered from dust
 * Connecting rod connects to other end
 * Link rod contains a telescoping slip joint with pin, to retain of modularity of track lengths

Horizontal Motion - Lengthwise
 * Festooned hydraulic hose
 * Hydraulic motor rides under the gantry
 * Engine moves carriage via a spool over which a wire is wrapped

Horizontal Dimension
 * Set by guides that are rolled out with a single crank

Automatic Feed Dust Ejector Set Works Log Holding
 * Separate hydraulic motor - with a riding bidirectional valve that trips its lever to other dimesion upon reaching end of track
 * Wire drives carriage
 * Have a safety trip in case of running into metal objects in wood
 * On top of blade guard
 * Set relationship of saw to the log to make the next cut
 * Dimensional sawmill needs setting in 2 dimensions
 * 2-stage dogs - one for staring the log (high center of gravity), and second for low center of gravity
 * May want to flip log if it's difficult to hold towards the end

Outstanding Design Issues

 * Hydraulic hose cabling guide
 * Multiple edger blades in future
 * Crank edger adjuster

Action Points
 * Saw collar

=Design=

CAD

 * http://openpario.mime.oregonstate.edu/projects/osusawmill/documents

Materials Sourcing

 * [10] 3/4" bearings for rollers on top of gantry-
 * Cam followers - 4x the cost -
 * [4] V-groove bearing for x (transverse) direction motion on inverted angle-
 * [4] 2-bolt, 1/2" flange bearing for y (lengthwise) motion - for pinion gear shaft
 * Rack - 8' -
 * [2] Main shaft pillow block bearings, 1-7/8" -
 * [2] Secondary blade pillow block bearings -

Fabrication
Blade
 * Anneal blade to machine
 * Harden blade by heating and quenching
 * Surface grind to flatness

Dogs
 * 1.25" square bar, sharpened to a 45 deg angle

Log Handling
 * CAT 966 was industry standard for large sawmills; largest logs are 14000 lb
 * John Deere 450 bulldozer - entry level, handy tool
 * Yale lift

Documentation

 * Z raising mechanism: worm gear for 4 posts, with adjustable wire tension
 * Y axis - transverse motion - gear rack with chain linkage