Understand & Use a Bowsaw

These traditional tools are woefully misunderstood by modern craftsmen. Here’s a primer.

In the 1970s when I was the young, innocent and naive chairmaker at Strawbery Banke, a museum in Portsmouth, N.H., 50,000 tourists passed through my shop each summer. It never failed that when I was cutting out a chair seat with a bowsaw some wag would quip loudly, “You need a band saw!”

While these comics guffawed at their own cleverness I was puzzled by the comment’s inanity. I knew I was doing just fine and didn’t need a band saw. I did my work quickly and efficiently with two different sized bowsaws – large and small.  The saws did all the work I required. I cut out two chair seats a week and four scrolled hands. If the chair had a crest, I cut that too.

The saws had cost very little, relative to a band saw. When I was done, I hung them on the wall, where they took up no floor space in my cramped shop. I was perfectly happy working this way.

After I had grown up and started demonstrating at woodworking shows, I continued to get the same comment from woodworkers who, carried away with their own wittiness, could not stop themselves from blurting, “You need a band saw!” It was then that I realized everyone thought I should have a band saw because they didn’t know about bowsaws. It was their loss. They missed out on the enjoyment of using a very efficient tool that has been around since the Bronze Age and was used in Europe and America to produce the great 18th-century furniture masterpieces we go to museums to admire.

Video: See a video of Mike Dunbar using a large and a small bowsaw.
Article: Read Frank Klausz’s article on the bowsaws in his shop.

Meet the Bowsaw, Moderner

In the history of woodworking there were many types of bowsaws, some developed by tradesmen to meet their own particular needs. For example, inlay makers cut out very small pieces with a fret saw, while wheelwrights cut out sections for wooden wheels (fellows) with a fellow saw. Today, we use far fewer bowsaws, but these share in common a number of features with all their ancestors. First is a thin blade that conserved on steel and allowed the bowsaw to change directions more easily than would be permitted by a flat-bladed handsaw. Second is a wooden frame that secures the blade. Third are the handles, which provide the user with something to hold, and which can be turned to adjust the direction of cut. Finally, every bowsaw has some method that tensions the blade – that is, stretches it tight.

For general woodworking – the sort of things most of us do – you need only two bowsaws. A large saw with about a 25″-long blade is great for ripping or cutting shapes out of heavy stock. A smaller saw with about a 12″ blade is better for cutting out smaller parts.

The biggest obstacle you face in adding bowsaws to your repertoire of woodworking skills is obtaining a saw. A lot of woodworking catalogs and web sites sell bowsaws, but beware: Most of these saws are cheaply made, lightweight and inadequate for woodworking. The same rule that applies to the lathe and workbench applies to the bowsaw. Flimsy equals worthless.

Why? Sawing requires force. The reason my large bowsaw is so efficient is that I can put a lot of weight and muscle behind it without the saw flexing or the frame wiggling. If either of these happens, the cutting action is less effective and the saw is harder to direct. My prejudice against commercial bowsaws is well founded. I have had one fall apart in my hands while cutting a chair seat.

Here’s a Good Bowsaw

These are the criteria to look for in a saw. You want a rigid hardwood frame, which will give the saw serious heft. The strut should attach to the ends with mortise-and-tenon joints. These should be deep and well fit, with no play or slop. You want the handle rods to be metal (usually brass). The rods should have a tight friction fit where they pass through the frame and secure the blade, so the blade cannot turn while in use. In other words, adjusting the saw should require effort. The blade should be secured to the rods by a slot pierced by a metal pin. All these parts should be robust enough not to wear or break. The strut and handles should be designed for comfort and have smooth relieved corners that will not raise blisters. I particularly like the octagonal handles on my saws.

You have to be able to tension or stretch the blade so it does not flex or twist. Most saws are tensioned by twisting a hank of string with a wooden toggle. I do not like wire that is tightened with a nut. This mechanism is not as effective. For string, I recommend waxed cobbler’s twine. It holds up well to years of use and does not stretch.

Most saws use a simple stick as a toggle for twisting and tightening the twine. Overlapping the toggle on the center strut keeps the twine from unwinding. However, the tighter you twist the twine, the tighter it becomes on the toggle. At some point the toggle will not slide at all and you can no longer tension the saw by full turns. This can be a problem, because over tightening can break the frame. The answer is the yoke with a sliding toggle as shown in the picture above.

The grooved yoke fits into the twisted rope, allowing the slotted toggle to slide freely. You can make full or half turns without any fuss.

And the Right Blades

The type of blade you choose to mount in your saw is determined by your intended use for the tool. I use my large bowsaw most frequently for cutting out chair seats. This means I am driving it through nearly 2″ of pine. I want my blade to be aggressive and fast. I don’t care if the cut leaves a coarse surface. When I am done, I will shape the edge of the seat and remove all evidence of the sawing. I use a length of 6 points per inch (ppi) 3⁄8“ band saw blade in the saw. Because I need the blade to be stiff and not flex, I use a .035″-thick blade rather than the more common .025″. You may not be able to buy this blade in your local woodworking store, but you can find it on the Internet and order online. The blade on my small bowsaw is a 16 ppi, 1⁄4“ saw blade.

If you make your own blades, you will have to drill holes for the pins that pass through the handle rods. The saw steel is too hard to drill, so soften the ends by heating them with a propane torch. Because most commercial bowsaws are inadequate, you are faced with either making your own or buying one from a craftsman/maker. 

Bench or Horizontal Sawing With the Large Saw

The large bowsaw cuts on the down, or push stroke, and the blade is mounted in this direction. The teeth are turned so they are at a right angle to the frame. A bowsaw is a turning saw, which means the blade can be turned so it is at a setting other than 90° to the frame, but I find I seldom do this. If you do need to turn the blade, loosen the toggle and turn the upper and lower handles at the same time. If you turn them separately, you risk twisting or breaking the blade.

The large saw cuts with the stock secured to the benchtop, so your bench needs to be the right height for sawing. Most modern benches are too high for most hand tools, and certainly for the large bowsaw. My test for proper bench height is to stand erect next to the bench with your arm straight and rigid at your side. Bend you hand at the wrist so it is parallel to the floor. The palm of your hand establishes the best height for your bench. If your bench is too high for the bowsaw, either trim the legs or stand on a platform when sawing.

Secure the work to the bench with clamps that are heavy and strong enough to hold it fast. How you position the stock on the bench depends on the work. To be as efficient as possible, here are a couple things to consider before beginning. With the big saw you travel along with the tool. Make sure you can move your body freely.

You do not want to stop and reposition your stock any more than is necessary. If you are ripping, clamp the stock to the bench so the kerf is close to the edge. This reduces any chance of the stock flexing. Short pieces and round shapes such as chair seats are easiest to cut with the stock clamped to a corner, although you will have to reposition the seat blank at least once. If in cutting a shape you have to cut around corners with a radius longer than your saw’s throat, trim the corners first.

A bowsaw has limitations. Like a band saw, its throat is only so wide. The maximum for my big saw is 61⁄2“. This means the saw works best for ripping narrow lengths and is useless when it comes to cutting plywood panels.

With the work secured, you are ready to use the saw. Grip it in the manner I am about to describe. Hold the strut near the top with your dominant hand (I’m right-handed) and grip the upper handle with your other hand. Stand facing the direction of cut, so the saw is in front of you.

Any hand-driven saw works best with a smooth stroke that uses almost the entire length of the blade. The same applies to a bowsaw. Also, any saw works best and requires the least effort if you use it properly. With a large bowsaw, the best advantage comes from using your entire body rather than your arms. Sawing is an aerobic exercise, and if done correctly you will not become fatigued or winded. 

To prepare for the down stroke raise the saw until the lower end of the blade is engaged on the line. As the saw descends use the entire length of the blade almost to the upper end. On the down stroke, come up slightly on your toes. Your heels will come off the floor. Flex your knees and bend slightly at the waist. This action, rather than your arms, is what moves the saw. While you cannot avoid some movement of your shoulders, it is surprising how little your arms are involved. Mostly, your arms and shoulders hold the saw in the cutting position while your body moves it. Raise the blade not with your arms, but by straightening your body and rocking your feet back flat on the floor.

You can understand the efficiency in this motion. Rather than trying to drive the saw with your arms and shoulders, you are putting the weight of your torso behind the blade.

At the end of the down stroke, pull the saw blade back slightly in the kerf. This accomplishes several things. First, the end of the kerf is tighter, so withdrawing the blade slightly makes it easier to lift the saw. Withdrawing the blade also clears trapped sawdust out of the kerf, especially at the end where you are cutting.

Finally, withdrawing the blade makes sawing more accurate. Here’s why. As you start the next down stroke you reposition the blade on the line. Repeat this with every stroke. While this continuous correction will create a more ragged edge than that left by a band saw, an experienced bowsawyer has less trouble with drifting off line. When you are done and examine the sawn edge, you can see where you started each stroke.

The key to using the bowsaw efficiently is to make the movement repetitive and fluid. Any halting or jerkiness indicates you are doing something wrong. Once you have achieved skill with the tool, you will be amazed at how efficient and fast a bowsaw is.

When ripping with the large bowsaw, hold the saw so the frame is tilted away from you. Because it’s on a diagonal, more of the blade is in the kerf, and it is easier to stay on the line. The kerf’s leading edge – below the surface – is angled and still aligned with the line you are following.

As you cut a curve, bring the frame into vertical, so it is cutting in the same manner as a band saw. If you tilt the frame as you do when ripping, the cut around the curve will be beveled, rather than at a right angle to the surface.

Vertical or Vise Sawing

The small saw is intended for detail work and for cutting out small parts. It simply does not have the heft to cut heavy stock. As with the big saw, I generally position the blade at a right angle to the frame. Like a coping saw this tool, too, cuts on the pull stroke rather than on the push.

The pull-stroke grip requires holding the saw by both handles. Because your arm reaches over the work, it cannot be secured horizontally on a benchtop. Instead, the work is held vertically in a vise. With the small saw you generally have to stop and adjust the work to give the saw access to more of the pattern, but this is a lot faster and easier than adjusting clamps.

Once again, the saw’s action needs to be smooth and use as much of the blade length as practical. In use, the small saw’s stroke is fast. Imagine yourself as a human scroll saw. Each pull stroke cuts and advances the kerf. On the back stroke, lift the blade slightly and reset it on the line before the next cut.

Operating the small saw is the opposite of the larger. While the big saw uses your entire body but not your arms, the small saw uses just your arms and shoulders but not your body. Plant your feet and bend your knees to bring your shoulders down to the height of the work. Retain this position. Lock your wrists and move the saw with your elbows and shoulders.

Storage is Simple

When you are finished with a bowsaw, release the tension on the blade. Turning the toggle backward one turn is sufficient. You don’t want to loosen the frame so much that it falls apart. I store my saws by hanging them on the wall. However, bowsaws lie flat and can be stored in a tool box. If you do this, find a way to protect the blade from other tools, and to protect you from it.

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