Field guide for concrete cutting and core drilling

1. Start with the structure, not the calculator

Before a calculation is useful, the input data must be correct. Check the actual wall or floor thickness, the materials and layers, and that all measurements use the same reference. For through-work, assess both sides.

2. Determine what happens when the piece is released

For cut-outs, finished dimensions are only part of the planning. Estimate the mass, consider the centre of gravity, and decide how the piece will be secured, lifted, lowered or divided before the final cut releases it. A 1.0 × 0.5 × 0.2 m concrete piece is about 0.10 m³; at 2,400 kg/m³ it weighs roughly 240 kg.

3. Plan the cutting sequence before the first cut

Decide which cuts come first and which cut finally releases the piece. At the same time consider water, slurry, access for the saw and rail, operator space and where the piece can move.

4. Remember that a circular saw blade has geometry

A blade cannot create a square internal corner through a thick structure without passing the corner at the surface. Required overcut depends on thickness and cutting depth. If visible overcut is unacceptable, plan corner drilling or another method before cutting.

5. For angled core drilling: define the angle clearly

A common error is mixing an angle from the surface with an angle from the normal. Write down the reference used. With angled drilling the bore path becomes longer than the straight wall thickness and the entry and exit points shift.

6. Check rigging space, not just the hole centre

A mathematically possible hole can still be impractical. Check room for the stand, fixing, motor and bit through the full travel. Account for edges, floor, ceiling, pipes and other obstacles.

7. Stitch drilling requires control of the whole contour

Holes must overlap enough to avoid continuous concrete bridges, while excessive overlap creates unnecessary drilling. Corners and free forms need extra attention because the bit can move outside the intended contour.

8. Divide large sections for handling, not just area

Equal areas are not always equally practical pieces. Long, narrow or L-shaped sections can have an awkward centre of gravity even when the weight is acceptable. Plan piece size together with lifting route, clearance and how the piece can be rotated or lowered.

9. A simple check before starting

Measurements and thickness checked from a clear reference; rear/underside checked and secured; services and relevant structural conditions clarified; approximate weight and handling assessed; cutting/drilling sequence and rigging space decided; water and slurry planned; overcut or corner drilling clarified; marking checked once more before starting.

What Concrete Cutter calculates – and what it does not replace

Concrete Cutter is made for quick geometric and practical field calculations. These calculations can reduce manual errors and speed up marking, but they do not replace assessment of the structure, hidden services, lifting equipment, fixings, machine capacity, work method or site-specific safety.