Reviewing an article from thefabricator.com, they listed several best practices for sawing structural tube. Below are some of the industry publication’s tips:
1) Look for variable clamping pressure. This allows for the vise-clamping pressure to be reduced to prevent deformation of thin-wall tube. The pressure should be enough to hold the tube firmly to ensure it doesn’t move, but not enough to bend it.
2) Watch for the weld orientation. Although quality saws will cut a tube regardless of the weld orientation, a fabricator should position the weld at the top or side of the saw entrance, rather than at the bottom, to maximize tool life. (Note: In a bottom-up cutting configuration, the weld should be at the bottom or on the side.)
3) Be aware of blade bias. When cutting non-round tubing in a band saw, it is preferable to have a bias on the blade (ie, a canted head). This is valuable for both good cut quality and longer blade life. Having the blade penetrate the material at an angle allows the fabricator to use the most efficient tooth configuration and prevents overloading of the blade gullet. Even a 1- to 3-degree bias will do the trick; a very large bias, however, will add to the overall cut time.
4) Pay attention to tooth geometry. Using the correct tooth geometry for a particular application helps to ensure a quality cut, while also prolonging the blade life. Although it is possible to use one type of blade for most structural tube applications, fine-tuning it for longer production runs is worth the additional effort. As a general rule, a fabricator using a band saw wants six to 12 teeth to be exposed to the widest part of the cut.