Step 1: Crafting the Wheels
Embark on your DIY bandsaw mill project by first manufacturing the essential wheels. Select a 3/4 inch thick Medium-Density Fiberboard (MDF) sheet, known for its affordability and ease of machining. Aim for wheels approximately 16 inches in diameter. To achieve perfect circular shapes, utilize a beam compass—a versatile tool for drawing precise circles—then carefully cut out the two matching wheels using a fine-toothed saw. Ensuring both wheels are identical in size and shape is vital for smooth operation.
Step 2: Creating and Attaching the Pulley
Next, fabricate a pulley to fit onto the wheel, facilitating effective blade drive. Use a 3/4 inch thick plywood sheet to cut a pulley with a diameter of about 7.5 inches. Drill a centered 5/8 inch hole in the pulley to accommodate the shaft. To prevent slippage and maintain alignment, affix a stock collar onto the pulley with hot melt glue, ensuring a secure, permanent bond. Before assembly, prepare a small spacer disc—glued between the pulley and wheel—to act as a precise distance buffer. Secure the pulley to this spacer, then attach the entire assembly onto the wheel, ensuring alignment and stability.
Step 3: Installing Wheel Bearing Blocks
For smooth rotation, bolt two wheel bearing blocks onto each wheel using four 3/8 inch threaded rods. The rods should fit snugly into the wheel’s holes but allow for movement of the bearing blocks. To prevent lateral shifting during use, apply a sturdy construction adhesive at the corners of the bearing blocks. This step ensures that the wheels rotate freely and stay aligned throughout the milling process.
Step 4: Building the Frame
Construct the foundational frame using salvaged 2×4 lumber, selecting straight, warp-free boards. Smooth the edges with a hand planer for a clean fit and improved stability. Position the supporting beams to hold the wheels, placing the stationary drive wheel 8.5 inches from the frame’s end. Drill two 5/8 inch holes in each supporting frame to house the axles, with an adjustable hole on the opposite side for fine-tuning wheel position. Create an adjustment collar out of plywood, bolted into the frame and attached to the shaft, to facilitate precise wheel alignment. To reinforce the structure, add cross braces across the frame, securing supporting boards firmly and preventing unwanted movement during operation.
Step 5: Installing the Front (Top) Wheel
The front wheel, or top wheel, serves dual functions: lateral movement for blade tension adjustment and tracking control. Fabricate two small sliding pieces that lock onto the shaft of the front wheel, allowing back-and-forth movement. Incorporate guide pieces to ensure straight sliding paths, preventing wobbling. Drill a 1-inch hole into the slider and secure a 3/8 inch threaded rod with a nut and washer, enabling blade tension and tracking adjustments during operation. Prior to mounting the blades, coat the wheels with silicone caulking to smooth surfaces and reduce friction, offering an advantage over bicycle inner tubes that can cause surface draping and additional resistance. Secure sturdy gusset blocks made from plywood or MDF to the legs to enhance stability during cutting.
Step 6: Mounting the Motor
Attach the motor onto the frame using a robust melamine board, affixed to the side of the stationary wheel with screws. This configuration provides vital support and bracing to prevent rocking or instability during cutting. Ensure the motor is centered and level relative to the blade before fixing it firmly with additional screws and bolts. Proper alignment is key to efficient operation and safety.
Step 7: Installing Blade Guides
For safety and blade longevity, install blade guides near the bottom of the saw. Use a small steel angle piece glued to a ceramic block to craft the guides, which serve to keep the blade aligned and prevent twisting. These guides do not contact the blade while in motion but constrain it should it attempt to move vertically or laterally. Incorporate a thrust bearing composed of standard ball bearings bolted onto an aluminum angle, attached to the guide assembly, to help maintain blade position and reduce heat generated from friction, thereby extending blade life and ensuring consistent cuts.
Step 8: Constructing a Dolly Cart
To facilitate the movement of large maple logs through the saw, build a mobile dolly cart with 2×4 boards and castor wheels. Secure the castors onto the ends of the boards using quarter-inch bolts, positioning them to allow smooth, single-direction movement. This cart simplifies log transportation, minimizes effort, and enhances safety during the milling process. The design ensures stability and ease of maneuvering, making your homemade bandsaw mill both practical and efficient.
Image Credits: John Heisz – Speakers and Audio Projects