Crosscut saw

Crosscut saw
A five-foot lance-tooth crosscut saw

A crosscut saw is a saw that is specially designed for making crosscuts. A crosscut is a cut made horizontally through the trunk of a standing tree, but the term also applies to cutting free lumber. "Crosscut saw" is a blanket term that includes smaller traditional carpentry saws and larger saws used for forestry and logging work.

Crosscut saws have teeth that are designed to cut wood at a right angle to the direction of the wood grain. The cutting edge of each tooth is angled back and has a beveled edge. This design allows each tooth to act like a knife edge and slice through the wood (in contrast to a rip saw, which tears along the grain, acting like a miniature chisel). Some crosscut saws use alternating patterns of the cutting teeth along with others, called "rakers", designed to scrape out the cut strips of wood. Cross saws have much smaller teeth than rip saws.

Some saws, such as Japanese saws and those used by the ancient Egyptians, are designed to cut only on the pull stroke. Western saws, on the other hand, are designed and sharpened to cut on the push stroke.

Contents

Common features

Many crosscut saws have a wooden handle with the return edge at right angles to the un-toothed edge of the saw blade, allowing the saw to serve as a square for marking material to be cut at a right angle.

Larger saws used for forestry and logging work include both one-man and two-man saws, and both bucking and felling saws. A bucking saw generally has a straighter back and less of a pronounced curve on its cutting surface. Since bucking saws are more often used on trees that are already downed, the greater stiffness and weight aids swift cutting, and allows two-man saws to also be used by one person, pushing as well as pulling.

A felling saw is generally less stiff than a bucking saw and the backside, as well as the cutting side, is usually curved inward. Felling saws are more often used to cut down standing trees, so the thinner, lighter design is easier to use without gravity holding the blade against the cut. The concave back of the saw makes it easier to place wedges, preventing the kerf from closing on the saw.[1]

A crosscut saw of the type used for carpentry

Crosscut saws also include smaller hand saws used in carpentry.

How crosscut saws cut

Common tooth patterns found on crosscut saws.

As described above, saws may have cutters, rakers, and gullets.

As the saw is pulled toward the operator, the cutters along the saw's surface score the wood to the left and right of the width of the blade, cutting a channel downward into the wood. Many sawtooth patterns have 4 cutters; each cutter that cuts to the left of the blade is paired with another that cuts to the right of the blade.

After the cutters there is generally a raker followed by a gullet. A raker is what does the actual removal of the wood that is being cut. The raker follows the cutters, scraping the bottom of the kerf. As the raker scrapes the bottom of the kerf, the wood is peeled back and stored in the gullet which follows the raker.

As the saw is drawn out of the kerf, the wood that has accumulated in the gullets is allowed to fall out onto the ground. A way to determine whether a saw is working well is to examine the noodle shaped strings of wood that are scraped out of the kerf; the presence of fairly long strings indicate that the side cutters are doing their job and that the raker is slicing out the wood cleanly.

Crosscut saws vs. chainsaws

Crosscut saws are much safer to use than gasoline powered chainsaws. When backpacking equipment into the forest, crosscut saws require less weight to be carried in on people's backs, and less maintenance is required for crosscut saws than for chainsaws.

In many areas gasoline powered saws aren't permitted, either because the area has been designated as a Wilderness Area or because fire restrictions or other restrictions are in effect.

Depending upon the skill of the operator and the types and width of the wood being cut, crosscut saws can be faster to use than chainsaws.

One of the reasons why crosscut saws are safer to use than chainsaws is that crosscut saws don't continue to cut after they're dropped. Another reason is that using a crosscut saw requires more time to size up the situation and think about the lay of the land and the direction in which bucked log sections might fall or travel than is taken by a typical chain sawyer, who usually likes to move quickly from downfall to downfall.

History

Crosscut saws have been in use around the world since historic times, with the design of the saws (the cutting surfaces, the bow and shape of the saw, and the handles) changing over time to accommodate differences in the types of trees being cut, changes in metallurgy technology, and the application of experience. Records exist of crosscut saws in use during the Roman Empire although not widely[2]. They came into wide usage in Europe in the middle of the 15th century. Early saws had a plain tooth pattern until the M tooth pattern was developed in 15th century south Germany. Prior to about 1880 crosscut saws were primarily used for bucking, with axes used to fell trees. Starting in Pennsylvania about 1880, loggers began using the saws for felling trees as well. Despite the modern chainsaw, they are still in wide use around the world, not only in competition matches against chainsaws but also in regular, real-life usage since they afford certain advantages over gasoline-powered saws.

Vintage saws versus modern saws

There are two types of crosscut saw classification, vintage and modern. Vintage saws are saws that can be anywhere from 30 to as much as 250 years old and are much sought after by professionals, and as such are typically very much more expensive than modern crosscut saws. Modern saws are typically stamped out of sheet metal and are manufactured from contemporary alloys which behave much differently than vintage saws which have historically been made by craftsmen who understood the nuances of the saws they produced.

In September 2005, the United States Forest Service conducted field trials of vintage saws against modern saws, details of which can be found in the external link reference provided below. One significant finding in the background research findings is that vintage saws are becoming increasingly difficult to locate owing to the demand for such saws by professionals.

Overall, modern saws have some advantages over vintage saws such as stiffness which is useful for felling but might cause difficulties when bucking downed trunks which have bind. Vintage saws which bend easily and can, in fact, be folded end-to-end for carrying on one's back, afford easier transport than most modern saws, and afford less-binding cuts that aren't straight.

Crosscut saw training

San Gabriel Mountains Trailbuilder volunteers get safety training.

Many areas of the National Forests of the United States are designated as Wilderness Areas and as such the use of mechanized and motorized equipment is prohibited except by special circumstance. Because of this, the United States Forest Service (USFS) organizes the crosscut saw training of USFS employees and forest working volunteers in an effort to maintain skills and proficiency among those who need to use such saws.

Training within the Angeles National Forest concentrates greatly upon the safety of the USFS employees and forest volunteers, the safety of animals in the area, and the safety of the surrounding environment.

Training also includes an examination of the differences and benefits of vintage saws and modern saws created with modern materials. Vintage saws are those saws which were manufactured over fifty years ago, being made of high carbon steel instead of the exotic alloys which are typical of contemporary saws.

Crosscut saws are used with a variety of other small hand tools. Wedges are usually used to keep the sections of the log being cut in place as the saw is worked through the rest of the log. Wedges are placed to keep the sections apart but tie wedges may also be applied across the cut to hold sections together until the sawyer is ready for the sections to roll or drop out of the way.

Also covered in typical training sessions is the safe use of the common axe. To keep the saw from cutting through rocks and dirt, the bark of the tree around the area to be cut is often removed with an axe.

Crosscut saw training is mostly safety training with the mechanics of working safely with top bind, bottom bind, and radial (twisting) bind comprising much of the training required to work with such saws. The establishment of escape routes for both felling and bucking may require that both operators at either end of a double-handled saw be constantly aware of the environment around them, and constantly aware of other people within the immediate region which might enter in to the sphere of crosscut influence.

Traditionally over the past 250 years the use of crosscut saws in the many forests of the United States lacked the use of safety clothing and equipment however safety training in contemporary usage in the United States dictates the mandatory use of gloves, eye protectors, chainsaw boots with hard tops and high-top ankle protectors, and possible ear protectors, Kevlar chaps, and long sleeved shirts.

Crosscut saws are used within Designated Wildernesses where chainsaws are banned due to the prohibited use of petroleum-based tools and equipment, requiring that crosscut training also include the proper use of non-petroleum based lubricants as well as training in techniques which leave a minimal impact both ecologically as well as visually after trails are cleared of downed trees.

See also

References

  1. ^ http://www.fs.fed.us/t-d/pubs/htmlpubs/htm77712508/page03.htm
  2. ^ Miller, Warren. Crosscut Saw Manual. Missoula: USDA Technology and Development Center, 1978, p. 2

External links


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Look at other dictionaries:

  • Crosscut saw — Saw Saw, n. [OE. sawe, AS. sage; akin to D. zaag, G. s[ a]ge, OHG. sega, saga, Dan. sav, Sw. s[*a]g, Icel. s[ o]g, L. secare to cut, securis ax, secula sickle. Cf. {Scythe}, {Sickle}, {Section}, {Sedge}.] An instrument for cutting or dividing… …   The Collaborative International Dictionary of English

  • Crosscut saw — Crosscut Cross cut , n. 1. A short cut across; a path shorter than by the high road. [1913 Webster] 2. (Mining) A level driven across the course of a vein, or across the main workings, as from one gangway to another. [1913 Webster] {Crosscut saw} …   The Collaborative International Dictionary of English

  • crosscut saw — n. a saw with a blade designed to cut across the grain of wood: see SAW1 …   English World dictionary

  • Crosscut Saw (song) — Cross Cut Saw Blues Single by Tommy McClennan B side You Can t Read My Mind …   Wikipedia

  • crosscut saw — noun handsaw that cuts at right angles to the grain (or major axis) • Syn: ↑crosscut handsaw, ↑cutoff saw • Hypernyms: ↑handsaw, ↑hand saw, ↑carpenter s saw …   Useful english dictionary

  • crosscut saw — /krɒskʌt ˈsɔ/ (say kroskut saw) noun any saw designed to cut across the grain, as a handsaw or a panel saw, but especially a large saw with a handle at each end …  

  • crosscut saw —    A saw with fine teeth set and angled to cut transversely through the grain of a dense material, usually wood. Also see circular saw, kerf, and ripsaw …   Glossary of Art Terms

  • crosscut saw — cross′cut saw′ n. bui a saw for cutting across the grain • Etymology: 1635–45 …   From formal English to slang

  • crosscut saw — noun Date: 1645 a saw designed chiefly to cut across the grain of wood compare ripsaw …   New Collegiate Dictionary

  • crosscut saw — a saw for cutting wood perpendicular to the grain. [1635 45, Amer.] * * * …   Universalium

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