What bandsaw blade do I need for cutting cast iron?

A carbide-tipped blade is the standard choice. The tungsten carbide tips cut through the hard, abrasive skin without blunting the way conventional teeth do. A trimetal blade such as the Bahco Easy-Cut Xtreme EZX also covers the structural, stainless and tool steels most shops cut alongside their castings.

Can I cut cast iron with a bi-metal blade?

You can on softer, well-cleaned castings, but the skin and the abrasive graphite structure blunt high speed steel teeth quickly, so cost per cut usually favours carbide. If the casting is chilled or heavily scaled a bi-metal blade will struggle from the first stroke; move to a carbide-tipped or grit blade.

What blade for chilled or heavily scaled castings?

A tungsten carbide grit blade. It has no conventional teeth, just an edge coated in carbide grit, so there is nothing for the hardened skin to blunt. It abrades through material that would strip the tips off a toothed blade. The Dakin-Flathers Saw37GRIT is the economical option for this kind of work.

Material guide

Bandsaw blades for cast iron

Cast iron's hard skin and abrasive graphite blunt conventional teeth fast. Carbide-tipped blades cut cleanly through the skin while tungsten carbide grit edges handle chilled or heavily scaled castings that defeat toothed blades.

Shop carbide-tipped blades Find my blade

The problem with cutting cast iron

A casting never presents a clean, uniform face to the blade. The skin carries residual moulding sand, scale and often chilled zones that are far harder than the metal beneath. A conventional toothed edge meeting that skin rubs rather than cuts, so the tooth rounds over quickly. Once the corner has gone the blade makes heat instead of chips and the wear accelerates from there.

The body of the casting is no kinder. Cast iron does not form the long, continuous chip that steel does; it breaks away as short, powdery fragments and the graphite structure that produces them is abrasive. Every stroke scours the tooth face and flank, so even a blade that survives the skin is being steadily lapped away by the material it is cutting.

The answer is an edge harder than anything in the casting. Tungsten carbide tips stay hard far beyond the temperatures that finish a high speed steel edge, so they shear through skin and body without losing their geometry. Where the iron is chilled or heavily scaled, a tungsten carbide grit edge goes further: with no teeth to blunt, it simply abrades its way through.

Recommended blades for cast iron

Constructions and ranges from the manufacturers' published data, with the honest reason each blade makes the list. Every one is welded to your machine's length.

Recommended blades for cast iron, drawn from the manufacturers' published ranges. Prices are from prices per welded loop, ex VAT, at the narrowest width and shortest length.
Blade	Construction	Width range	Why this blade	From price
Easy-Cut Xtreme EZX Trimetal Bandsaw BladeBahco 3859	Tungsten carbide tips on an alloy backing, some further coatedCarbide-Tipped Blades guide	27mm to 54mm	Bahco rates this trimetal carbide blade for cast iron alongside structural, stainless and tool steel, so one blade covers the castings and the general work around them.	From £45.00 ex VATsample pricing
Saw37GRIT Tungsten Carbide Bandsaw BladeDakin-Flathers Saw37GRIT	Steel band edge-coated in tungsten carbide grit or diamond, no conventional teethGrit and Diamond-Coated Blades guide	6mm to 38mm	Its tungsten carbide grit edge has no conventional teeth to blunt, making it the economical choice for chilled, scaled or otherwise abrasive cast iron.	From £54.00 ex VATsample pricing

Getting the cut right

General rules that hold across machines. Exact widths, pitches and options are on each product page.

Match the edge to the casting
For most cast iron a carbide-tipped blade cuts cleanly through the skin and holds its edge in the abrasive body. Where the casting is chilled, heavily scaled or carrying trapped sand, choose a tungsten carbide grit edge instead: with no teeth to blunt, it keeps cutting where a toothed edge would round over.
Get through the skin quickly
The skin is the hardest part of the cut, so do not baby the blade through it. A positive, steady feed keeps each tooth biting beneath the surface rather than rubbing on it; light feeds let the teeth skate on the hard skin, which is exactly what blunts them. Once through, hold the feed consistent to the far side.
Set the machine up rigidly
Interrupted, abrasive cutting punishes a loose setup. Tension the blade properly, bring the guides as close to the work as the casting allows and clamp the piece so it cannot rock as the section changes. Castings are rarely uniform, so expect the load to vary through the cut and let a rigid setup absorb it.
Keep the swarf clear
Cast iron cuts as fine, powdery swarf rather than curled chips. That powder is abrasive wherever it settles. Clear it from guides, wheels and wear surfaces regularly, then brush the blade so the gullets do not pack. If it grinds between band and wheel it wears the machine as effectively as it wears the blade.

Suggested image

Action shot: recommended blade cutting cast iron, cut face visible

materials/cast-iron/cutting

Industry guide

Non-Ferrous Metals and Foundry

Cutting cast iron for a living? The industry guide maps the whole workload, not just this material.

Read the guide

Other material guides

Frequently asked questions

Tell the wizard your machine and length and it will match cast iron to a blade that fits.

Find my blade