skip to Main Content
Here is a list of the common blade failures and their causes, and some maintenance tips to extend the life of your saws. Article by Dake Corp.

Caring for Your Bandsaws

Caring for Your Bandsaws

Here is a list of the common blade failures and their causes, and some maintenance tips to extend the life of your saws. Article by Dake Corp.

There are many types of saw blades available for your metalworking cold saw or band saw depending on the use of the saw. Not only that, there are many new types of saws being introduced all of the time. This can cause a lot of confusion when trying to determine the best saw blade for your application.

Here is a list of five of the most common saw blade types for metalworking and their advantages so you never have to second guess your decision again.

  1. Carbon Hard Back: One-piece carbon steel construction; spring tempered backing with an RC of 43–47 (for rigidity) and a tooth RC of 64–6. Advantages include low cost; resists swagging and scoring; and accepts heavier feed pressures. These result in faster cut rates.
  2. Carbon Flex Back: One-piece carbon steel construction; spring tempered backing with an RC of 31–37 to allow flexing and a tooth RC of 64–66. Advantages are low cost and greater fatigue life. The blade back flexes to minimize back fatigue and fractures; and reduction in blade hardness occurs at about 148.9 deg C (300 deg F).
  3. Bi-Metal (Matrix): A blade made from two dissimilar metals; steel spring backing with high-speed steel edge material welded to tips of the teeth. The high-speed steel often contains 8 percent cobalt for extreme wear characteristics. Advantages are: fatigue resistance; resists back edge swaging; operates at high band tension for straighter cuts compared to carbon steel blades; and reduction in blade hardness occurs at 704 deg C (1300 deg F).
  4. Carbide Tipped: Welded carbide to the tips of each tooth and welded to a high strength alloy backing. Ground for triple chip—every other tooth has a double bevel rather than a straight tooth. Advantages include its ability to cut harder materials; the best finish on non-ferrous applications; greater strength and heat resistance; and eliminates tooth set collapse.
  5. Grit Edge: Tough alloy backing material with tungsten carbide or diamond grit fused to the edge of blade. These blades can have either straight edges or gulleted edges for gummy materials. This type of saw can cut abrasives or very tough materials and can run at higher blade speeds.

Common Saw Blade Failures

Making sure your saw blade is working properly is the best way to reduce downtime and increase production. There are many common causes that can cause blade failure—from blade selection to cutting speeds, feed rates and improper break-in, to maintenance problems, and more. In order to help you extend the life of your blade, here is a rundown of some of the most common blade failures and their causes.

  1. Heavy wear on tips & corners of teeth
  • Blade speed is too fast for material generating high heat at tips causing rapid wear.
  • Feed rate is too low causing teeth to rub material instead of cut.
  • Coolant is the wrong type or mix and is not cooling the blade properly.
  • The material being cut is hardened or abrasive. (i.e. Fiberglass abrasive)
  1. Wear on sides of teeth
  • Not enough teeth set allowing teeth to rub in kerf.
  • Teeth may be hitting guides or machine causing rapid wear on one side of blade.
  • Speed is too fast for the type of material being cut causing extreme temperature at teeth.
  • Blade is too wide for radius being cut (Mostly seen on vertical band saws)
  • Material very hard or abrasive.
  1. Chipped or broken teeth
  • Handling damage
  • Feed rate or feed pressure is too high
  • Improper break-in
  • Wrong tooth pitch
  • Teeth may be hitting part of the machine
  • Hard material is being cut or hard surface scale
  • Hard spots in material
  • Material is not positioned or clamped properly, or there is movement of material during cut
  • Wrong type or lack of coolant
  • Chip brush is not cleaning teeth properly
  • Improper butt-weld on blade
  1. Tooth stripping
  • Feed rate or feed pressure is too high
  • Improper break-in
  • Wrong tooth pitch
  • Teeth may be hitting part of the machine
  • Hard material is being cut or there is hard surface scale
  • Hard spots in the material
  • Material is not positioned or clamped properly or there is movement of material during cut.
  • Wrong type or lack of coolant.
  • Chip brush is not cleaning teeth properly
  • Improper butt-weld on blade
  1. Chips welded to teeth tips
  • Feed pressure is too high
  • Chip brush is not removing chip causing it to fuse to teeth tips
  • Band speed is too fast, creating high temperatures
  • Wrong type or lack of coolant
  • Material make-up: Some materials such as Titanium have chip-welding tendencies.
  1. Tooth gullets loaded with chips
  • Tooth pitch is too fine for the material, leading to insufficient chip clearance
  • Excessive feed pressure is producing extra-large chips for gullet size
  • Chip brush is not working, adjusted, or missing
  • Coolant problems
  1. Heavy wear on side of blade
  • Guide adjustment is too close/tight
  • There are worn guides that do not ride on the blade properly
  • Blade guide is out of alignment
  1. Scoring on side of blade
  • Worn or broken guides
  • Blade guide is out of alignment
  • Band is rubbing on some part of the machine
  • Chip removal is inadequate
  • Abrasive material is being cut
  • Blade is too wide for the radius being cut. (Most seen on vertical saws)
  1. Cracks in gullets
  • Blade too wide for band wheel radius
  • Improper guide alignment
  • Excessive blade tension, feed pressure, or blade speed
  • Improper blade tracking
  • Teeth contacting guides
  • Nicks or scratches in blade backing
  • Worn, missing or defective back-up guide
  • Side guide out of alignment
  • Improper blade tracking
  1. Cracks in the side of the blade
  • Guide is too tight, hardening the blade and causing cracks.
  • Defective side guides

All of the blade failures on this list are preventable! Below are some blade maintenance tips to extend the life of your saw:

  1. Keep cutting area clear of metal chips

Just like you don’t want salt from the winter ruining your car’s paint job, you don’t want metal chips to ruin your saw blade. Keeping the cutting area clean will prevent stray chips from running through the kerf during the cut. Having a properly adjusted chip brush is also critical in cleaning chips from your saw. Make sure the brush just ‘kisses’ the teeth of the saw blade.

  1. Make sure all fluids are fresh and at the proper level

Having fresh coolant with the proper mixture will extend the life of your saw blade. Check to make sure that coolant has the proper flow. Changing the gearbox oil on a regular basis will give you a smoother cut. Don’t forget to check the hydraulic oil level often. This will extend not only the life of the blade, but the life of the saw.

  1. Check that guides and the blade are properly aligned

All blade guides must be able to operate freely, have proper alignment and adjustment in order to obtain top performance. Proper alignment of the saw’s blade track is critical. Wheels that are not in alignment can damage blades by riding low on one wheel and tight against the lip of the other. Improper tracking can cause swagging of the edge and popping of the saw blade off the wheels. If this happens, the blade will have a camber and will be very difficult to track in the future.

  1. Perform operation checks and test the machine set up regularly 

Having a machine that is set up properly is the best way to maintain smooth operation of your saw and saw blade. Correct operation of the machine will provide less maintenance problems, higher cutting capacity, and will extend the overall life of your machine tool.

Follow these saw blade maintenance tips on a regular basis and you are guaranteed to be happy with the performance of your saw for years to come!

 

WANT MORE INSIDER NEWS? SUBSCRIBE TO OUR DIGITAL MAGAZINE NOW!

FOLLOW US ON: LinkedIn, Facebook, Twitter

 

 

How Industrial Robots Increase Sawing Productivity
Back To Top