Band Saw Blade Pitch, Speed, and Cut Time

The whole pitch rule is that between three and twenty-four teeth must be engaged in the cut at any moment. Fewer than three and a tooth can straddle the work, catch a corner, and strip, which is how a blade dies on thin-wall tube in a single stroke. More than twenty-four and there is no gullet space for the chip, so the chips pack, the teeth rub instead of cutting, and the work hardens ahead of the blade, which is how a blade dies on stainless. Because the tooth count depends on the THICKNESS IN THE CUT rather than on the part's overall size, the answer changes continuously through a cut on a round bar or a tube -- which is exactly why variable-pitch blades exist and why they are the default for mixed work. A 2.0 in solid round wants between 1.5 and 12 TPI, so a 4/6 variable sits comfortably inside the band, and at 250 surface feet per minute on 12 in wheels the wheels turn 79.6 rpm and a 3.14 sq in cut at 5 sq in per minute takes 38 seconds. Now cut 2.0 in square tube with a 0.120 in wall: the thickness in the cut is the wall, so the band becomes 25 to 200 TPI and there is no such blade. That is the real lesson -- thin wall cannot satisfy the minimum-three-teeth rule with any practical pitch on its own, which is why thin tube gets bundled, nested, or cut fine and slow as a compromise. A selection aid; the blade manufacturer's pitch chart and the machine's own feed capability govern.

min_tpi = 3 / thickness_in_cut; max_tpi = 24 / thickness_in_cut; wheel_rpm = blade_speed_sfm x 12 / (pi x wheel_diameter_in); cut_time_min = cut_area_sqin / feed_sqin_per_min.

The three-to-twenty-four-teeth-in-the-cut band saw pitch rule, by name -- standard sawing practice published in every blade manufacturer's selection chart, cited and not reproduced. The blade manufacturer's pitch chart and the machine's feed capability govern.

The pitch rule is stated as a relation and cited to the manufacturers' published practice rather than reproduced from any chart; the section, blade speed, and feed are the shop's own values.

Estimate. AHJ and licensed professional govern.

Field names used by the API: thickness_in_cut_in, blade_speed_sfm, wheel_diameter_in, cut_area_sqin, feed_sqin_per_min, min_tpi, max_tpi, wheel_rpm, cut_time_min

• Three to twenty-four teeth engaged in the cut at any moment; below three a tooth strips, above 24 the chips packband saw blade selection practice
• Thickness in the cut the rule keys off the section the blade is passing through, not the part's overall size -- which is why the answer changes through a round or a tubeband saw blade selection practice
• Practical pitch limit the finest common bimetal pitch is an 18/24 variable; a requirement past 24 TPI cannot be stockedblade manufacturer catalogs