#082 — Circular Saw Table Saw

Circular saw inverted under a plywood table, blade through a slot. Add a fence. Budget table saw. Respect the blade.

Ratings

🧪 What Is It?

A table saw is just a circular saw mounted upside down under a flat table with the blade poking through a slot. That's it. The table provides a flat reference surface, the fence provides a parallel guide for rip cuts, and the inverted mounting means both hands are free to guide the workpiece instead of holding the saw. Build the table from 3/4" plywood, mount the circular saw underneath with the blade extending through a precise slot, add a straight fence that locks parallel to the blade, and you have a functional table saw for free. Commercial table saws cost $200-800. This one costs your time and attention to safety.

🔨 Build Steps

1. Build the table frame. Construct a sturdy table from 2x4 legs and a 3/4" plywood top, sized at least 24"x36". The table must be flat and rigid — any flex or wobble is dangerous with a spinning blade. Make the table waist-height for comfortable work.
2. Mark the blade slot. Place the circular saw upside down on the underside of the table top. Position it so the blade will be about 8-10" from one long edge (this is your rip capacity). Trace the blade path — you need a slot just barely wider than the blade kerf.
3. Cut the blade slot. Drill a starter hole, then cut the slot with a jigsaw. Keep the slot as narrow as possible — a wide slot is a safety hazard (small offcuts can fall through and jam). The slot should be long enough for the blade to extend its full cutting depth above the table.
4. Mount the circular saw. Secure the saw upside down to the underside of the table with bolts through the saw's base plate. The saw must be rigidly mounted — any movement during cutting is extremely dangerous. Use large washers and lock nuts. The blade should protrude about 1/4" above the height of the material you're cutting.
5. Wire the saw. Secure the trigger in the ON position with a zip tie or clamp (the trigger lock feature on most saws helps here). Wire the power cord through a switch mounted on the front edge of the table for easy on/off access. This switch is your primary control — you need to be able to kill power instantly.
6. Build the rip fence. Mount a straight piece of aluminum angle or flat bar parallel to the blade slot. The fence must be perfectly parallel to the blade — any angle causes binding and kickback. Use bolts in slots for adjustment, with clamps or wing nuts to lock the fence position. Check parallel with a tape measure at both ends.
7. Make push sticks. Cut at least two push sticks from scrap wood — these keep your hands away from the blade while feeding material. A push stick should have a notch on one end to hook the workpiece edge and a comfortable grip on the other. ALWAYS use push sticks for cuts narrower than 6 inches.
8. Add a blade guard (strongly recommended). Fabricate a clear acrylic or sheet metal guard that covers the blade above the table. Commercial table saws have riving knives and anti-kickback pawls — without these, your DIY table saw is more dangerous than a commercial one. At minimum, build a clear guard that prevents accidental hand contact with the blade.
9. Test with scrap. Power on and cut a piece of scrap wood. Check: Is the cut straight? Is the blade height correct? Does the fence lock securely? Does the workpiece feed smoothly without binding? Fix any issues before real work.
10. Establish safe work habits. Never stand directly behind the blade (kickback zone). Always use push sticks for narrow cuts. Never remove the fence during a rip cut. Never cut freehand. Keep the blade sharp — dull blades cause binding and kickback.

⚠️ Safety Notes

Spicy Level 3 build. Read the Safety Guide before starting.

• This is the most dangerous build in this category. Table saws cause more woodworking injuries than any other tool. A DIY version without commercial safety features (riving knife, anti-kickback pawls, flesh-sensing technology) is inherently riskier. Build and use a blade guard. Use push sticks religiously. Never reach over or behind the blade. Respect the blade at all times.
• Kickback is the primary hazard — it occurs when the workpiece pinches the blade or contacts the rising teeth at the back. The blade can launch the workpiece back at the operator at high speed. Always use a rip fence for rip cuts and keep material firmly against the fence throughout the cut.
• Wear safety glasses, hearing protection, and a dust mask. Do not wear gloves (they can catch the blade and pull your hand in), loose sleeves, or jewelry. Tie back long hair.

🔗 See Also

• Hand Drill Press
• Router CNC Spindle