Electric Mini Sawmill

This is a small sawmill using an electric chainsaw, similar to an Alaskan sawmill except that the saw is fixed and the wood moves. It is suitable for slabbing small logs that can be finished in an electric planer. The maximum log diameter is about 13 inches, the maximum length about 4 feet.

Material: electric chainsaw, threaded rod, nuts, washers, plywood, 2x4 lumber, screws, dowels, switched electrical outlet.

I used a chainsaw with a 16" bar and 3/8" threaded rod. Drill two holes in the saw bar, as far apart as possible, making sure not to get too close to the motor housing (leave clearance for a nut) or damage the chain sprocket at the end of the bar. The bar material is typically hardened and difficult to drill. I started with a small good-quality twist drill and ended up blunting a few drills, filing the hole out, and using carbide-tipped masonry bits to finally get a 3/8" hole.

The bed is made from 3/4" plywood reinforced with 2x4" stringers underneath. There's a 2x4" piece at the back of the bed, which guides the log, made in two pieces with a gap in the middle.

The threaded rod goes through the saw bar, through the bed and into a piece of 2x4 screwed underneath. The original version of the sawmill had only that much support, but the rods bent in use. The current version adds a plywood arch to support the top end of the rods. The top of the arch is removable to allow removal of the chainsaw. There are a couple of dowels for alignment, and two screws to hold it in place.

There are a total of 6 nuts and 4 washers per rod, plus two lock washers, From the underneath, the sequence is nut, washer, 2x4, plywood, washer, nut, space, nut, chainsaw bar, lock washer, nut, space, nut, washer, plywood, washer, nut. The height of the cut is adjusted by screwing the nuts up and down the rods. The chainsaw body needs some support to avoid bending the bar. I originally used wooden blocks underneath but the current build has a rope suspended from the shelter roof. The arrangement could be improved.

(In the photo, there are extra washers either side of the chainsaw bar. I had to remove those when I slabbed a log that barely fit between the rods; the washers were catching on the log, and they aren't really necessary)

The basic idea is to slide the log against the running saw. Since the bottom of the log is probably not flat and the log won't slide in a predictable way, I screw a flat piece of lumber into the flattest side and then slide that along the bed. Sometimes it helps to place strips of wood between this flat and the rear wall of the bed; in operation using the top edge of the saw to cut, the saw pushes the log against the wall.

For easier control of the sliding pressure, there is a simple lever pivoted on a bolt that can exert force on the end of the log. As the log moves down the bed as the cut progresses, I add pieces of 2x6 lumber to push it further.

The chainsaw has a momentary-action trigger switch. In order to use the saw continuously, I tape the trigger down and control the saw with a switched outlet box

The photo shows a couple of slabs before planing