Saws are extremely efficient at cutting almost any material. Many metalworking shops underutilize their sawing dollars by machining or grinding material that could be sawed more efficiently. Sawing is more efficient because the operation’s thin kerf minimizes material waste and typically requires less horsepower to remove material than other processes. And the chunk scrap produced by sawing has a higher per pound value than chips from turning or milling.
If you’re just setting up a shop and thinking about what kind of saw to get, I strongly suggest a vertical bandsaw. It’s highly versatile and can cut almost anything—from meat to hardened steel to even glass. The key factors when selecting a vertical bandsaw are speed range and throat depth. Buy the maximum you can afford for both.
You can TIG weld bandsaw blades with silicon-bronze rod (top). Then grind the weld on a curved surface to remove weld buildup and level the seam (middle). After grinding, peen the weld area on a flat dolly to level the seam so blade thickness is correct (bottom).
One of the great abuses of bandsaws is not changing the blade for cutting thicker material or different alloys. If I had unlimited floor space and a budget to match, I would have three vertical bandsaws, each set up differently to accommodate different materials and alloys.
The rule of thumb for blade pitch is to use lots of smaller teeth for thin stuff and fewer but bigger teeth for thick stuff. For most purposes, a shop can get along with two blade pitches. This helps reduce confusion for people who don’t reference the blade chart.
Band saw blades are often purchased in bulk on a roll, and in some operations the saw blade is intentionally cut prior to use. As a result, the blade ends often must be welded together.
If you don’t have a blade welder or you run out of silver solder, you can tungsten-insert-gas weld bandsaw blades with silicon-bronze rod. The weld is annealed a second time after grinding to remove brittleness along the heat-affected zone. Be sure to accurately line up the blade spine or it will make clicking noises as it runs through the guides.
After you weld, silver solder or otherwise connect the two stray ends of a bandsaw blade, remove the weld buildup and level the seam. Use a curved surface to expose the weld area to your grinding or other preferred abrasion operation. After grinding, peen the weld area on a flat dolly to level the seam so blade thickness is correct.
Before sawing with any kind of saw, protect critical surfaces with tape. A good grade of masking tape works well for a cutting guide as well.
Other types of saws that make a good investment are circular and miter saws. Use a woodcutting circular saw to cut aluminum plate. Be sure to wax the blade. Use the cheapest carbide-toothed blades you can find because high-quality blades don’t seem to last any longer. I have cut 2 "-thick copper with this setup. If you use a guide, you almost have a plate saw.
A woodcutting miter saw makes short work of aluminum and plastics. I add a fence with a recessed scale to prevent scraping off the stick-on ruler. With this setup, sawing 4 "-dia. aluminum is a snap.
Use a push stick to sweep the scraps off the saw table. Sweep from behind the blade toward you. If you were to accidentally hit the blade, you would get a good scare but still have all your fingers because the last time I checked there are no teeth on the back of the blade. CTE
About the Author: Tom Lipton is a career metalworker who has worked at various job shops that produce parts for the consumer product development, laboratory equipment, medical services and custom machinery design industries. He has received six U.S. patents and lives in Alamo, Calif. Lipton’s column is adapted from information in his book “Metalworking Sink or Swim: Tips and Tricks for Machinists, Welders, and Fabricators,” published by Industrial Press Inc., New York. The publisher can be reached by calling (888) 528-7852 or visiting www.industrialpress.com. By indicating the code CTE-2011 when ordering, CTE readers will receive a 20 percent discount off the book’s list price of $44.95.
Related Glossary Terms
- alloys
alloys
Substances having metallic properties and being composed of two or more chemical elements of which at least one is a metal.
- bandsaw
bandsaw
Machine that utilizes an endless band, normally with serrated teeth, for cutoff or contour sawing. See saw, sawing machine.
- bandsaw blade ( band)
bandsaw blade ( band)
Endless band, normally with serrated teeth, that serves as the cutting tool for cutoff or contour band machines.
- bandsaw blade ( band)2
bandsaw blade ( band)
Endless band, normally with serrated teeth, that serves as the cutting tool for cutoff or contour band machines.
- circular saw
circular saw
Cutoff machine utilizing a circular blade with serrated teeth. See saw, sawing machine.
- flat ( screw flat)
flat ( screw flat)
Flat surface machined into the shank of a cutting tool for enhanced holding of the tool.
- gang cutting ( milling)
gang cutting ( milling)
Machining with several cutters mounted on a single arbor, generally for simultaneous cutting.
- grinding
grinding
Machining operation in which material is removed from the workpiece by a powered abrasive wheel, stone, belt, paste, sheet, compound, slurry, etc. Takes various forms: surface grinding (creates flat and/or squared surfaces); cylindrical grinding (for external cylindrical and tapered shapes, fillets, undercuts, etc.); centerless grinding; chamfering; thread and form grinding; tool and cutter grinding; offhand grinding; lapping and polishing (grinding with extremely fine grits to create ultrasmooth surfaces); honing; and disc grinding.
- heat-affected zone
heat-affected zone
That portion of the base metal that was not melted during brazing, cutting or welding, but whose microstructure and mechanical properties were altered by the heat.
- kerf
kerf
Width of cut left after a blade or tool makes a pass.
- metalworking
metalworking
Any manufacturing process in which metal is processed or machined such that the workpiece is given a new shape. Broadly defined, the term includes processes such as design and layout, heat-treating, material handling and inspection.
- milling
milling
Machining operation in which metal or other material is removed by applying power to a rotating cutter. In vertical milling, the cutting tool is mounted vertically on the spindle. In horizontal milling, the cutting tool is mounted horizontally, either directly on the spindle or on an arbor. Horizontal milling is further broken down into conventional milling, where the cutter rotates opposite the direction of feed, or “up” into the workpiece; and climb milling, where the cutter rotates in the direction of feed, or “down” into the workpiece. Milling operations include plane or surface milling, endmilling, facemilling, angle milling, form milling and profiling.
- pitch
pitch
1. On a saw blade, the number of teeth per inch. 2. In threading, the number of threads per inch.
- sawing
sawing
Machining operation in which a powered machine, usually equipped with a blade having milled or ground teeth, is used to part material (cutoff) or give it a new shape (contour bandsawing, band machining). Four basic types of sawing operations are: hacksawing (power or manual operation in which the blade moves back and forth through the work, cutting on one of the strokes); cold or circular sawing (a rotating, circular, toothed blade parts the material much as a workshop table saw or radial-arm saw cuts wood); bandsawing (a flexible, toothed blade rides on wheels under tension and is guided through the work); and abrasive sawing (abrasive points attached to a fiber or metal backing part stock, could be considered a grinding operation).
- sawing machine ( saw)
sawing machine ( saw)
Machine designed to use a serrated-tooth blade to cut metal or other material. Comes in a wide variety of styles but takes one of four basic forms: hacksaw (a simple, rugged machine that uses a reciprocating motion to part metal or other material); cold or circular saw (powers a circular blade that cuts structural materials); bandsaw (runs an endless band; the two basic types are cutoff and contour band machines, which cut intricate contours and shapes); and abrasive cutoff saw (similar in appearance to the cold saw, but uses an abrasive disc that rotates at high speeds rather than a blade with serrated teeth).
- turning
turning
Workpiece is held in a chuck, mounted on a face plate or secured between centers and rotated while a cutting tool, normally a single-point tool, is fed into it along its periphery or across its end or face. Takes the form of straight turning (cutting along the periphery of the workpiece); taper turning (creating a taper); step turning (turning different-size diameters on the same work); chamfering (beveling an edge or shoulder); facing (cutting on an end); turning threads (usually external but can be internal); roughing (high-volume metal removal); and finishing (final light cuts). Performed on lathes, turning centers, chucking machines, automatic screw machines and similar machines.
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