‘Saw What You Did There…’
Sinking some teeth into a vital machining process that sometimes gets taken for granted.
Sawing, in all its forms, is a process between raw bar stock and finished parts for a vast majority of manufacturers. Some use it to remove a blank from bar stock to send to a machine to be cut into a finished part. Some use it as a final operation (fabricators, I am talking to you), and the remainder use it as a de facto finishing process. 80/20 Inc. comes to mind as a member of the latter group.
There are also different forms that sawing can take, some examples include: conventional band sawing using a continuous band of bi-metal saw blade with any given pitch (teeth per linear inch), chop saws that use a circular blade much like that of a table saw blade or a miter saw in a wood shop, and cold sawing that uses either a rubber-reinforced wheel or a fiberglass-reinforced cut-off wheel. This list is by no means exhaustive, but more of a primer on the matter.
Let’s start off by digging into these listed methods for now.
Bandsaws
First, let’s tackle the most common method of conventional band sawing, both vertical (see Figure 1) and horizontal. Every shop I have ever worked in had a pair of vertical bandsaws, one with a finer pitch blade for ferrous, stainless steels and tougher materials, and one with a more coarse pitch blade for non-ferrous materials such as aluminum, plastics and wood. All good repair and service shops have adopted this model. As to the pitch of a blade, as an example, a 10-pitch blade is 10 teeth per inch, or one tooth per 0.100″. This is a good all-purpose blade pitch for everything from wood and plastics to aluminum and most soft machine steels, with finer-pitch blades used for special applications where an overly coarse pitch would lead to an over aggressive cut, leading to damage to both the saw and/or your bar stock or part.
A standard rule of thumb for our vertical bandsaws is that at least three or four teeth should be engaged in the material being cut whenever possible. This reduces the risk of shearing off the teeth of your blade. Super thin sheet metal being the only exception in our shop. The blade is tensioned inside the machine with only the necessary amount of space between the table and the upper blade guide exposed. With the machine on, you gently feed your material into the path of the saw blade, usually following a crude layout line to cut off your desired part or blank from the bar stock. Our machines also have a blower that is powered by the upper tensioning wheel that blows a stream of cool air right at the cut zone to help clear chips, cool the part, and prevent the overload of the teeth and gullets (which causes blade pop, or the dislodging of the blade from the tension wheels or a blade snap at the weld). Make good use of it if you have one on your saw.
On the horizontal saw, which in our shop has a variable pitch saw blade to be able to accommodate anything short of super tough or hardened materials, you clamp the bar stock in the on-board vice at the desired cut-off length, turn the saw on and wait until coolant starts to flow. Then you set your blade speed, your blade down feed, and start the cutting cycle. Once the blade passes through the stock, it trips a limit switch that shuts off the saw blade and coolant pump. There are some limitations in this machine and in this method that I will now lay out.
Firstly, the distance between the vice jaws and the blade guides. This means if your bar stock is too short, you cannot safely grip it for a cut. Also, if your part is so short that it sits too far from the center point of the vice jaws, the jaws pivot and don’t properly hold the part.
But wait, there are solutions! As many of you who’ve read my past works may know I partake in a healthy diet of “Cheaties” and have come up with ways to get our saw to cut parts that are too short for the jaws to hold in a conventional sense. See Figures 2 and 3 for samples of my methods.
To put it simply, I have used bars of sacrificial material to extend the reach of the jaws so I can still clamp shorter parts reliably. Another method I rely on for cutting shorter pieces is to put a “dummy” piece of identical width in the back half of the vice while clamping on my part toward the front end of the jaws. This evens out the clamping forces and prevents the jaws from tilting. The latter method is used both with and without the sacrificial bars to extend the reach of the jaws.
Chop Saws
Now I’ll dive into chop saws (see Figure 4). These saws use a circular blade just like you’d see in a wood shop on either a table saw, radial arm saw or miter saw. The tooth geometry merely being optimized for cutting metals and other materials over only woods. The use of the chop saw is rather straightforward. You clamp your workpiece in the included vice at the desired length (whether cutting off a blank or trimming something to length), turn the blade on, and advance the saw right through the material. An excellent example that comes to mind is the one I mentioned at the beginning of this article, 80/20 Inc. As an option on their website, you can order pieces of their extrusions cut to a custom length, and, judging by the finish on the ends of the bars, a chop saw was the perfect solution used for this type of work.
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March 2026
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