How to Easily Resharpen Bandsaw Blades

Resharpen Bandsaw Blades Overview: This article will focus on how to easily resharpen your dull bandsaw blades using common tools. If you are a woodturner, chances are you already own a bandsaw or will soon. Bandsaws in a woodturning studio are very versatile and useful tools. As woodturners, we typically work with and cut lots of salvaged green (wet) wood, which may contain foreign materials like nails, rocks, wire, bullets and similar hard materials that can dull our bandsaw blades very quickly.

Even when the timber you're cutting is free of these foreign materials, the extractives in green wood can be very damaging to the sharp edges on your band's teeth. Sooner or later you are going to want to resharpen your dull bandsaw blades - or be content to go broke buying new ones! Ask any woodturner who has cut green Red Oak just how fast it can rust and dull a brand new band. In addition, certain timbers are highly abrasive, containing large amounts of silica, which can dull bands in short order as well.

Several years ago when I first opened my studio, I was amazed just how fast green wood could dull a new bandsaw blade. There were times when I mounted a new band on the bandsaw and a minute or two later, it was dull as a butter knife. When the band hits a rock, or an embedded nail, it's toast. Back then, my only option was to replace the band and mull over the wasted $25.00. Of course, most of the bands lasted quite a while before they became dull, but it's always the short-lived ones that stick out in your memory.

18" Laguna ACM
Production Bandsaw

One day whilst working in the studio processing some logs and stumps for bowl blanks, I hit a rock and I lost the edge on my band. Luckily, I had a few more on hand and I quickly removed the dull band, mounted a new one and continued processing. Shortly thereafter, I hit another rock. I replaced the second band, and kept going. Not long after, the third and fourth bands were also toast from cutting these very abrasive timbers and hitting the occasional foreign object. I was soon down to my last sharp band.

Dull bandsaw blades no longer need to be thrown out. Simply resharpen them using my technique

These particular timbers were very abrasive and some contained small rocks that had grown into the wood. None of the rocks were visible on the exterior of the timber. My chainsaw found a few rocks in the initial bucking and the bandsaw found a few more during post processing. Not long after my fifth and last band was mounted on the bandsaw, I hit yet another rock and my last band was now dull.

With no more sharp bands in stock and no way to get new bands on a long holiday weekend, I was dead in the water. I had to get the burr processed, but without any bands my only choice was to use the chainsaw. Since the kerf on the chainsaw chain is much wider than the bandsaw blade, that choice was rejected. When you are working with high figured and expensive timbers, you want to get as much out of them as you possibly can. That means reducing waste to the absolute minimal amount.

As I pondered my dilemma, I decided to find a way to resharpen the bandsaw blades myself. Necessity being the mother of invention, I began to scour through all of the tools in my studio, looking for something that might work.

A standard high-speed rotary tool with an abrasive disc can easily be used to resharpen bandsaw blades

After considering and then rejecting numerous tools and grinding accessories, I found just what I was looking for, a high-speed rotary tool. Its small size and light weight were ideal for working under the limited space under the blade guides.

After a considerable amount of experimentation with different styles and shapes of abrasive tips, cut-off disks and diamond disks, I was able to develop a simple protocol to resharpen my bandsaw blades on the bandsaw quickly and easily.

Protocol to Resharpen Bandsaw Blades

Proper safety equipment
is essential!

  • Unplug your saw. You should wear a full-face safety shield or safety glasses during the sharpening to protect your eyes.
  • You should also wear an appropriate respirator, or dust mask to protect you from the abrasive/metal dust that is generated.
  • Set up a good strong light (100 watt) that illuminates the bandsaw blade clearly.
  • Use a small stool, or an adjustable height mechanics stool that will allow you to sit with your eyes inline with the cutting zone.
  • While wearing a pair of gloves, rotate the blade one complete revolution, checking for stress cracks, or other damage to the band. If any defects are discovered, throw the blade out.
  • Never try to resharpen bandsaw blades that have defects for safety reasons.
  • If the band passes the safety check, mount a thin abrasive cut-off disk or a diamond disk onto the appropriate mandrel and chuck it into your rotary tool. I use a Dremel rotary tool, but any of the small rotary tools will work.

Dremel tool outfitted
with abrasive disc

  • Apply just enough tension to keep the blade straight, whilst you rotate it with your gloved hand. The gloves protect your hands from the band and teeth edges, which can have sharp edges as you rotate the band to sharpen it.
  • Turn your rotary tool on and set the speed to 5,000 – 10,000 RPM. With your left hand, grip the band and pick the starting tooth you want to begin sharpening. Use your right hand to control the rotary tool to safely resharpen bandsaw blades.

Close-up of 1.3 TPI band

Front view of
resharpened band

  • The teeth on the blades are set in a particular way, depending on the type of blade and its intended usage. Some teeth are straight inline with the body of the blade; others curve right, or left.
  • There are two main parts to the tooth, the back of the tooth (mostly flat portion) and the front of the tooth (curved gullet portion). To resharpen the tooth, you will be lightly grinding the back of each tooth, in one or two light strokes.

Sharpening a centre tooth

  • As you begin the resharpen the tooth, you will see the bright metal on the back of the tooth revealed. This bright metal back edge of the tooth should extend all the way to the end (tip) of the tooth.
  • One or two very light strokes are all that is necessary, a light kiss of the abrasive on the back edge of the tooth.
  • As you sharpen each tooth, rotate the flat face of the abrasive or diamond disk so it matches the direction and curvature (right, left, or centreline) of each tooth.
  • This means you must move your wrist as you sharpen each tooth. The centreline teeth require your wrist to be directly in centreline with the band. The left curved teeth, require you to move your wrist to the left, the right curved teeth, require you to move your wrist to the right and so on. Therefore, before you resharpen each tooth, move your wrist into position and then proceed to resharpen the tooth.

Sharpening a left tooth

Sharpening a right tooth

  • As you complete the sharpening of each tooth, rotate the blade down a bit with your gloved hand to bring the next tooth into position and resharpen the next tooth. The resharpened surface on the back of the tooth should feather into the original shape of the tooth.
  • Continue resharpening each tooth until you have resharpened every tooth on the band. You can mark the starting tooth with tape or a black marker to assist in determining the original starting tooth.
  • It sounds more complicated than it is in practice. The first time I resharpened one of my bands it took almost 30 minutes. Now, I can resharpen bandsaw blades in less than 3 minutes, start to finish. Once you get used to the motions required and get comfortable with the protocol, you will be able to resharpen bandsaw blades very quickly.

Watch a Short Video on the Bandsaw Resharpening Protocol

This one minute, twelve second video clip is presented using flash player. If you do not have the latest flash player, you will be prompted to download it when you click the play button on the viewer below.

Please note: Due to the compressed nature of Internet video, the image on the preview clip below may be slightly degraded based on your connection speed or monitor settings.

Watch a Short Video on the Bandsaw Resharpening Protocol

This one minute, twelve second video clip is presented using flash player. If you do not have the latest flash player, you will be prompted to download it when you click the play button on the viewer below. Please note: Due to the compressed nature of Internet video, the image on the preview clip below may be slightly degraded based on your connection speed or monitor settings. Untitled Document

Suitable Bands for Resharpening

The majority of the bandsaw bands in my studio are 1.3 or 2.3 Teeth Per Inch (TPI) bands. These are the best bands for resawing wet wood, which accounts for 90% of my cutting activities on the bandsaw. Occasionally, I will use fine tooth blades, but I rarely resharpen bandsaw blades like these. Finer tooth blades can be resharpened successfully, but require more time and progressively smaller abrasive or diamond wheels to accommodate the smaller clearances required to sharpen each tooth.

Obviously, my resharpened bandsaw blades are not as good as brand new, or even professionally resharpened blades. However, they are sharp afterwards and allow me to continue cutting with a minimum of downtime and expense. I can usually get about 8-10 sharpenings per blade when using abrasive disks and up to 20 resharpenings per band when fine diamond disks are used.

If I were resawing paper-thin veneer, I would not use one of my resharpened bands; I would use a brand new blade. However, most woodturners use their bandsaw for general gross cutting activities like making turning squares, cutting bowl blanks, cutting blanks into rounds, thickness cutting etc. For these types of non-critical cutting activities, the resharpened bands will perform very well. The quality of the cut is dependent of the quality of the resharpening, but the protocol is not that difficult to learn.

Note: Check the abrasive disk after it has been used to resharpen bandsaw blades 10 times and replace as necessary. If you are using fine diamond disks to resharpen bandsaw blades, the life of the diamond disk will be significantly longer than the abrasive disks.

Resharpen Bandsaw Blades - Abrasive and Diamond Disks

My original protocol to resharpen bandsaw blades uses abrasive cut-off disks in the Dremel tool; however, you can also use small fine and super-fine diamond disks to resharpen bandsaw blades. Diamond disks actually produce a higher quality sharpened surface because you have more choice over the abrasive grit range with diamonds than the abrasive wheels.

If you prefer to use diamond disks to resharpen bandsaw blades, choose fine or super fine grit wheels for the best quality sharpened surface. With the abrasive or the diamond disk wheels, use a very light touch when sharpening each tooth. It is quite easy to remove too much metal, reducing the overall life and cut quality of each blade.

Close-up of abrasive
cut-off disc

Resharpen Bandsaw Blades, Tooth by Tooth

For a more thorough sharpening, you can elect to sharpen the entire tooth, (front and back) instead of just the back portion only. Since most of my bandsaw work is gross resaw work, sharpening only the back portion of each tooth is faster than sharpening the entire tooth, which requires two separate operations.

To sharpen the entire tooth, a supplemental sharpening protocol and abrasive attachment is required. Round cylindrical abrasive, or diamond stones are used to sharpen the front of each tooth. Long thin stones that are very close to the gullet size of the tooth work best.

Sharpening diagram

The front of each tooth is sharpened much the same way as the back portion, using a very light touch. Gently raise the stone under each tooth to sharpen the front, curved area of each tooth. If you have the capability to reduce your rotary tool to 5,000 rpm’s, a slower speed will make the tool and the stone easier to control, especially when sharpening the front gullet portion of the tooth.

When sharpening the front portion of the tooth, take care to keep good control of the tool. The rotation of the stone coupled with the curvature of the tooth can make to stone “race” along the curvature of the tooth. Use a firm grip to control the movement of the stone under the tooth. This is easier than it sounds, but does require a bit of extra care.

Resharpen Bandsaw Blades - Closing Thoughts

It does take a bit of practice to be able to resharpen bandsaw blades using this protocol, but when you do, it can save you a lot of time, money and aggravation. Some may argue that it’s easier to just buy a new blade, but if your blade goes dull on a weekend and you’ve got a few bowl blanks to process, you’ll appreciate being able to continue sawing with a minimum of fuss and downtime. Try it and see for yourself how easy it is to resharpen bandsaw blades!

Need More Help? If you would like see Steve demonstrate how to resharpen bandsaw blades, check out our 2 hour, 20 minute step-by-step video on bowl turning, where the bandsaw resharpening protocol is included in the bonus features section of the video.

Safety Note: Always follow all manufacturers safety instructions before working with your lathe, or any of the tools or products you may use. If you are unsure about any operation, obtain competent professional instruction before proceeding. Use and wear all necessary safety devices during turning and observe safe woodturning practices to prevent accident or injury.

Steven D. Russell is a professional studio woodturner, teacher and writer. He has written numerous articles for international woodturning magazines, which have been published in more than 78 countries around the world. Steve has demonstrated in numerous cities across the United States. His studio, Eurowood Werks, specializes in bowls, platters and hollow forms with unique visual and tactile treatments.

Steve is also the current and founding President of the Lone Star Woodturners Association, Inc., an AAW member chapter. The LSWA is a 501(c)3 non-profit educational organization dedicated to teaching and demonstrating the art and craft of woodturning.

Steve is also a featured writer for the Guild of Master Craftsman's "Woodturning" magazine, published in London England. Woodturning magazine is the world's leading magazine for woodturners. Look for his articles covering technical topics, or project based articles in an upcoming issue.