On a typical wood or metal cutting blade the hook or of point of the blade should be pointing down for a vertical blade bandsaw, or for a horizontal blade saw the hook of the teeth should be pointed such that they enter the workpiece first as the blade moves. During regular cutting on a well set up bandsaw the blade will move or bow backwards a bit as you press the workpiece into it. The side guides will assist in keeping the blade cutting straight, but they are not an iron lock on the blade forcing it to cut straight.
The original question of the saw not cutting square vertically is due to the fact that the blade cuts in the direction its pointing. What has been missed so far is that if the arm doesn’t fall square to the vice table, the blade, even if adjusted as above, it will still not cut square vertically. To know if you’ve got this problem, using 6″ engineers square like in the photo above, place it so the blade of the set square just touches the tip of one of the teeth that is set toward the vice and clamp it up hard.
Another very common cause of not tracking square through a cut is blade tension. Blade tension on these little saws is high… higher than you might ever imagine. If the blade isn’t precisely 90° to the table then there’s no way you’re going to get a square cut, it WILL drift.
Being a happy bandsaw owner has a lot to do with your approach to coping with the fact that a bandsaw simply will not cut straight, or, in the sage words of veteran woodworkers, “Adjusting for drift.” Even the top performing 14″ bandsaw on the market, Powermatic’s 14 Bandsaw 1791216K, comes with a no-frills fence with 4 bolts on top rather than easy and obvious thumbscrews or knobs that say, “Adjust me here!”. Making the bandsaw cut nice and straight with this fence is a snap.
Unless you doing alot of scroll cutting on sheetmetal, I don’t recomend a “Vertical” bandsaw for straight cutting metal. Horizontal bandsaws will cut much staighter due to the fact that the material is clamped, and the saw is hinged on a stationary plane. This allows the blade not to bind, but also alows “Wiggle room” which allows the blade to cut curves or in your case wander and cut crooked.
how to get a metal bandsaw to cut straight Related Question:
Why is my band saw cutting at an angle?
A bandsaw has a spring that you tighten to keep the blade under tension. Your saw will probably have instructions for how tight to make the blade. This spring can loose its ability to properly tension the blade after some time, allowing the blade to twist in the cut.
Why won’t my bandsaw cut straight?
Band Saw: Why won’t my band saw cut straight? When the band saw cuts crooked, a dull blade, improper feeding, loose blade tension or not using a work piece guide could be the cause. Use the rip fence or miter gauge to guide the work piece uniformly through the cutting blade to make straight cuts.
Why does my metal bandsaw not cut straight?
Make sure the blade is running in the correct direction. On machines powered by three phases power so it is common to get the wiring reversed and have the blade running the wrong direction. On all vertical blade bandsaws the working portion of the blade should go down. This forces the workpiece down into the table.
How do you straighten a bandsaw blade?
How to straighten a bandsaw blade? It is risky but if it’s absolutely necessary, a temporary fix to straighten a bandsaw blade can be done by placing it on an anvil and gently tapping it flat with a nylon head hammer/mallet or using a pair of gas pliers to straighten out the blade.
What causes bandsaw drift?
Drift is cause because the blade buckles under the load. You can see that by stretching a ribbon between 2 points and applying a pressure to one of the edges, it will turn sideway easily. A sharp blade and high blade speed will help a lot with that.
Why do bandsaws wander?
Tim Inman: Because band saw blades ride on crowned wheels, they always have a little “camber” angle relative to the vertical axis of the wheel. This causes the blade to tip a little and makes the cut “pull” to the side.
Why are my bandsaw cuts wavy?
Re: Band saw Cutting Wavy Cuts. The clasic cause for wavy lumber is pushing a dull blade past it’s limits. Sharp don’t get it.
How much tension should a bandsaw blade be?
For carbon steel toothed blades (cutting blades) this is typically 15,000 to 25,000 PSI. Slitting type blades typically are tensioned in the range of 12,000 to 20,000 PSI. In general bandsaw blades are never tensioned past 35,000 psi.
Why does my bandsaw spark?
Ceramics can cause sparks. Or, if your thrust bearing is too far past the blade, more toward the center of the bearing than the edge, then it won’t turn and you’ll get sparks too, and possibly wear a groove in the bearing.