Log entry 04 — Wire sawing & specialty cuts
Wire sawing and the specialty bench: for concrete that outmatches a blade
Blades have a depth limit and a shape. When the concrete is too thick, too reinforced, too large, or too awkward for a blade — or the corner must be perfectly square — the specialty tools take over. This entry logs each one, what it is for, and what it costs in time and setup.
Wire sawing
A wire saw threads a diamond-beaded cable through holes drilled at the corners of the cut, then pulls the loop through the concrete with a drive pulley. Depth is effectively unlimited — bridge piers, mass foundations, dam and vault work, heavily reinforced beams and columns, and large equipment bases are cut this way. Wire sawing is quiet relative to breaking, produces a smooth face, and can work under water. It is also the slowest, most setup-heavy method: corner holes, pulley rigging, water management, and a safety exclusion zone for the cable path. It is specified when nothing else can make the cut, not as a default.
The rest of the bench
| Tool | Best work | Limits, honestly |
|---|---|---|
| Hand sawing (handheld diamond saws) | Shallow openings, step cuts, finishing wall-saw corners, small trenches, work where no track fits | Depth about 4–6 in. per side; operator-held, so long straight runs are wall-saw work; wet or vacuum-shrouded for silica control |
| Chain sawing (diamond chain) | Square corners with no overcut, deep narrow cuts (to about 24 in.), plunge cuts, openings in finished spaces where overcut tails are unacceptable | Slower and costlier per foot than blades; chain and bar wear is significant in abrasive aggregate |
| Curb sawing | Horizontal cuts at curb faces for driveway aprons and curb drops, cutting flush at the gutter line | A single-purpose machine; municipal curb work may need town DPW permission and traffic control |
| Ring saws | Deeper hand cuts (to about 10 in.) where a chain saw is not warranted | Still a hand tool — depth and length limits apply |
| Stitch drilling | Oversized or shaped openings made from overlapping cores; the fallback where no saw can go | Edges are scalloped by definition; slow; chosen for access or shape, not finish |
Pricing note. Specialty work is rarely honest as a simple per-foot list — setup dominates. Wire sawing is typically quoted per job after a site look, with mobilization, corner drilling, and rigging as visible line items. The cost ledger covers core, slab, and wall work with printed bands; for wire and chain work, describe the job in the request and expect the quote conversation to start with thickness, reinforcement, and access photos.
Choosing, in one paragraph
Under 6 inches and short: hand saw. A straight opening in a wall up to about 24 inches: wall saw, corners by chain or hand saw. Square corners with zero overcut tolerance: chain saw. Beyond blade depth, massively reinforced, or huge in section: wire saw. No access for any saw: stitch drilling. Any competent cutting contractor owns this logic — ask a quoter to walk it for your job and listen for whether the answer matches the concrete, not the equipment they happen to have free that day.