Chainsaw Milling and Alaskan Mills: Turning Logs into Rough-Sawn Lumber for the Home Shop

Every maker who works in wood eventually looks at a downed tree — a neighbor's storm-damaged oak, a felled backyard walnut, a load of free logs from a tree service — and wonders whether it's actually lumber waiting to happen. It is, and you don't need a bandsaw mill costing thousands of dollars to get there. A chainsaw mill, sometimes called an Alaskan mill after the classic Granberg design, turns an ordinary chainsaw into a portable sawmill that can slab logs right where they fall. It's slower and wastes more wood to kerf than a bandsaw mill, but for a home shop that wants a few slabs a year rather than a full-time milling operation, it's the cheapest and most accessible way to convert logs into rough-sawn lumber you can then dimension on the planer, jointer, and table saw already covered elsewhere on this site.

How a Chainsaw Mill Works

An Alaskan-style mill is a frame that clamps to the bar of your chainsaw, running parallel to it with adjustable height rails that ride along a guide — typically a straight edge, ladder, or the first flat cut you make. The chainsaw's own bar and chain do the cutting; the mill just constrains the cut to a consistent thickness as you walk the saw down the length of the log. The first pass, called the "slabbing cut," removes the rounded top of the log to create a flat reference surface. Every subsequent pass rides on that flat face (or on a straight edge clamped above it) to produce parallel slabs.

ComponentPurposeNotes Mill frame (Alaskan-style)Clamps to the bar, sets slab thicknessGranberg is the common reference brand; frames typically fit 20–36 inch bars Ripping chainCuts along the grain instead of across itStandard crosscut chain works but cuts far slower and rougher; a dedicated ripping chain (different tooth grind angle, ~10° vs ~30°) is the single biggest upgrade for milling Guide rail / ladderEstablishes the first flat cutA straight 2x4 or aluminum ladder clamped to the log works; some mills include their own guide bar PowerheadDrives the chainMilling is the hardest work a chainsaw will ever do — a 60cc+ saw is the practical minimum for anything wider than a small log, and big slabs favor 90cc+ saws Auxiliary oilerExtra bar and chain lubricationMilling runs the saw at sustained full engagement far longer than felling or bucking; many millers add a secondary oiler to prevent bar and chain wear

Choosing and Preparing a Log

Not every free log is worth the effort. A few things to check before you set up the mill:

• Metal detection first, always. Old fence wire, nails, and lag bolts hidden in bark are the single most common cause of ruined chains and dangerous kickback situations in urban and yard-tree milling. A cheap metal detector pass over the whole log before cutting is non-negotiable if the tree grew anywhere near a structure, fence line, or yard.
• Species and figure. Walnut, cherry, maple (especially spalted or curly), and oak are the classic high-value urban lumber species. Softer woods like pine and poplar are easier to mill but less rewarding for furniture-grade work.
• End sealing matters immediately. Logs that sit even a few days after felling start checking (cracking) from the ends inward as moisture leaves faster than it can migrate from the log's core. Coat both end grains with wax-based log sealer or even leftover latex paint before milling if there's any delay.
• Log diameter vs. bar length. Your guide bar needs to be several inches longer than the log's diameter to clear the cut. A 36-inch bar mills logs up to roughly 28–30 inches in diameter after accounting for the mill frame.

Setting Up and Making the Cut

1. Support the log off the ground on cribbing (smaller logs or dimensional lumber) so the bar has clearance underneath and the log won't roll.
2. Set up the guide rail for the first slabbing pass, checking level and that the rail is fully secured — any movement here telegraphs into every subsequent slab.
3. Make the slabbing cut in one continuous, steady pass. Rushing the feed rate is the top cause of stalled cuts and chain binding; let the ripping chain do the work at a slow, even walking pace.
4. Remove the guide rail, set the mill to your target slab thickness, and ride subsequent passes on the flattened top surface.
5. Sticker each slab immediately (thin wood strips between layers) to allow airflow, and move fresh-cut slabs out of direct sun to slow initial moisture loss and reduce checking.

After the Mill: Drying and Dimensioning

Freshly milled slabs are far from usable lumber — they need to dry slowly and evenly, and this site's wood moisture content guide covers the specifics of air-drying timelines and kiln options. As a rule of thumb, air-dried lumber loses moisture at roughly one year per inch of thickness, so a 2-inch live-edge slab needs about two years stickered in a covered, ventilated space before it's stable enough to build with. Once dry, the planer and jointer techniques already covered here bring rough-sawn faces to usable flat and parallel surfaces, and a CNC router sled is the standard way to flatten a slab wider than your planer's capacity.

Safety

• Chainsaw milling is significantly more physically demanding and slower than normal chainsaw work, and the saw is under sustained load for much longer stretches — full PPE (chaps, helmet with face shield, hearing protection, gloves) is essential the entire time, not just during felling.
• A saw under full engagement for minutes at a time overheats faster than during normal bucking; watch for bar and chain temperature and take breaks to avoid oil breakdown and chain stretch.
• Never mill a log you haven't scanned for embedded metal — a chain strike on buried metal at full engagement is a serious kickback and laceration hazard.
• Two people milling a large slab is safer and dramatically faster than one — a second person can manage the guide rail, clear sawdust, and watch the cut line while the operator focuses on feed rate.
• Keep the work area clear of bystanders; chainsaw milling throws a continuous stream of large chips and sawdust well beyond normal bucking distances.

A chainsaw mill won't replace a bandsaw mill for volume or precision, and the kerf loss from a wide chain is real waste you're paying for in wood. But for the maker who wants to turn one good log a year into a set of usable slabs — for a river table, a workbench top, or simple air-dried boards — it's a low-cost, portable entry point that turns free material sitting in a yard into project-ready lumber, using a tool most woodworking shops already own.