Choosing the right bandsaw blade matters just as much as choosing the right machine. Bi-metal and carbide grit are two of the most common blade types used for demanding cutting applications, and getting it wrong can mean slower cutting speeds, reduced blade life, or a blade that just isn't suited to the material you're cutting.
This guide explains the practical differences between the two, covering hardness, material suitability, cost and blade life, so you can make an informed choice based on the job in front of you rather than guesswork.
What Each Blade Type Actually Is
A bi-metal blade combines two materials in its construction. The teeth are made from high speed steel, typically M42 cobalt steel, while the body of the blade is a more flexible alloy backing. That gives the blade hard, heat resistant teeth without making the whole thing brittle, so it can flex around the wheels of the bandsaw without snapping.
A carbide grit blade works differently. Instead of conventional teeth, the cutting edge has tungsten carbide grit bonded or brazed on, either as a continuous edge or in a segmented pattern along the blade. The cutting action relies on abrasion rather than a tooth biting into the material, and that's exactly what allows it to handle materials a bi-metal blade simply can't.
The Case for Bi-Metal Blades
Suited to General Metal Cutting
Bi-metal blades are the general purpose choice for most metal cutting jobs, handling steel, stainless steel, tubes, bundles and solids up to around 39 HRC on the Rockwell C hardness scale. For structural steel sections, beams, bar and tube, they're the standard choice across most workshops.
Lower Cost
Bi-metal blades are considerably cheaper to buy and replace than carbide grit blades, which matters when a blade is going through regular wear as part of daily production. For any material within their hardness range, they're the more cost effective option.
Made in House and Available Quickly
Our BM42 bi-metal blades are manufactured in house at our factory in East Sussex, made to order with custom lengths and tooth pitches, and available with next day delivery on most orders.
The Case for Carbide Grit Blades
Built for Harder and More Abrasive Materials
Carbide grit blades are suited to materials that are abrasive, things like fibreglass, graphite, composites, cables and low density ceramics. Rather than cutting with a biting tooth action, the carbide grit grinds through the material, which is why it holds up where a standard bi-metal blade would wear down or chip within minutes.
Tool steels and cast iron are a different case, and generally come down to hardness rather than abrasiveness. Depending on the grade and hardness involved, either a bi-metal or a carbide grit blade can do the job, so the right choice comes down to the specific material spec rather than a fixed rule.
Two Styles for Different Jobs
Carbide grit blades are available with a continuous grit edge, which suits finer or thinner sections, or in a segmented pattern, which is generally better suited to larger workpieces.
The Cost Is Justified by the Job
Carbide grit blades cost more than bi-metal, and that reflects the specialist coating and the harder materials they're built for. It's generally worth it though, since for the right material there simply isn't a cheaper blade that will do the job properly.
Where the Trade-Offs Really Lie
The decision usually comes down to the material first and the machine second.
If the material sits clearly within bi-metal range, hardened tool steels aside, there's rarely a reason to spend more on carbide grit. Bi-metal will cut efficiently, hold an edge well, and cost less to replace.
If the material is hardened, highly abrasive, or falls outside standard metals altogether, a carbide grit blade is usually the only option that will cut cleanly and last.
Using a bi-metal blade on material it's not rated for can dramatically shorten its life, while using a carbide grit blade on soft, easy to cut material can actually work against you: the grit is prone to clogging or loading up on softer materials, which reduces cutting efficiency and can shorten the blade's life rather than just being an unnecessary expense.
It's also worth checking the blade against the specific bandsaw you're using, since not every machine is set up to run every blade type at the correct speed and tension.
A Simple Way to Decide
Before ordering, it helps to work through the following.
What's the hardness or type of material being cut? Check it against the 39 HRC and 45 to 65 HRC ranges above.
Is the material abrasive rather than just hard? Fibreglass, composites, graphite and ceramics point towards carbide grit regardless of hardness.
How large is the workpiece? Larger sections generally suit segmented carbide grit, while finer sections suit a continuous edge.
What's the budget for blade replacement over time? Bi-metal costs less per blade but wears faster on unsuitable material.
Is the blade compatible with the machine? Speed and tension settings need to match the blade type being used.
There's no universally right answer here. Plenty of workshops run bi-metal blades for the vast majority of their cutting and only reach for carbide grit on specific, harder jobs. The right choice is the one that matches the material actually going through the saw, not a general assumption about which blade is "better."
How SAWS UK Can Help
SAWS UK manufactures BM42 bi-metal blades in house at our East Sussex factory and supplies carbide grit blades welded to order for harder and more abrasive materials. Because we work with both, our advice isn't tied to selling one option over the other.
Tell us what material you're cutting and which machine it's going through, and our team can recommend the right blade type, tooth pitch and width for the job, with next day delivery available on most bi-metal orders. Get in touch with the team for advice or a quote on your next blade order.
Frequently Asked Questions
What's the main difference between bi-metal and carbide grit bandsaw blades?
Bi-metal blades have teeth made from high speed steel on a flexible alloy backing, suited to general metal cutting up to around 39 HRC. Carbide grit blades have tungsten carbide grit bonded or brazed to the edge instead of conventional teeth, allowing them to cut harder and more abrasive materials, up to around 65 HRC and beyond.
Can a bi-metal blade cut hardened steel?
Standard bi-metal blades are rated up to around RC 39, so heavily hardened steel above that range is better suited to a carbide grit blade, which can handle up to RC 55 or higher.
Are carbide grit blades more expensive than bi-metal blades?
Yes, carbide grit blades typically cost more due to the specialist tungsten carbide edge and the harder materials they're designed for. The extra cost is usually justified when the material genuinely requires it.
What materials need a carbide grit blade instead of bi-metal?
Carbide grit blades are suited to hardened steels, cast iron, fibreglass, graphite, composites, cables, low density ceramics and other abrasive materials that would quickly blunt a standard bi-metal blade.
Do carbide grit blades come in different styles?
Yes, they're available with a continuous grit edge, which suits finer or thinner sections, or in a segmented pattern, which generally suits larger workpieces.
How do I know which blade suits my bandsaw?
Check the material you're cutting against the hardness ranges above, then confirm the blade is compatible with your specific machine's speed and tension settings. At SAWS UK, we manufacture both blade types and can advise on the right match before you order.
What blade width should I use?
Blade width affects how tight a radius the blade can cut and how much beam strength it has for straight cuts. Narrower blades can follow curves for contour work, while wider blades resist wandering and stay straighter over longer, harder cuts. The right width depends on the machine's wheel size and the type of cut being made, not just the material.
What TPI (teeth per inch) should I use?
TPI needs to match the material thickness being cut, not just the material type. As a general rule, thinner material needs a higher TPI so at least two to three teeth are in contact with the material at any time, while thicker material needs a lower TPI to give each tooth room to clear chips without clogging. Too few teeth in contact causes snagging and poor finish; too many causes the blade to ride on top rather than cut.
What blade speed should I run?
Blade speed, usually measured in surface feet per minute (SFM), needs to match the material being cut. Harder or more heat sensitive materials need a slower speed to avoid excess heat build-up, which can blunt the blade or discolour the cut. Softer materials can run faster without the same risk. Running too fast for the material is one of the most common causes of premature blade wear.
Do new blades need breaking in?
Yes, new blades need a running in period before being run at full feed rate and pressure. This usually means making the first few cuts at a reduced feed rate, allowing the teeth to seat properly against the material. Skipping this step is a common reason new blades fail early, since the teeth can chip or dull before they've had a chance to condition properly.
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