can't get the bandsaw to cut straight

[Tom7227]

I have a Grizzly GO555 and I put a new 1/8 inch blade on it. I am cutting decoy blanks out of basswood that is about 4 1/2 inches thick. The bottom cut is off by about 1/8 inch. I tightened the tension and it was still happening. I am cutting about as slow as I can.

Suggestions on what I might be doing wrong?

Thanks for your time.

Tom

[Gordie]

Can you adjust the top or bottom guide rollers?

Sometimes the guide rollers look in place but when pressure is on them they move a bit.

I have a craftsmen band saw that doesnt always like to keep it vertical postion spot and I always have to adjust the stop for that too.

Its a turn crank that seems to loosen up due to vibration and like I said I have to recalibrate it everytime I use it.

Just something I have become a custom to.

[CAMAN]

Is the table square to the blade?

[mn_bowhunter]

Narrow blades are more likely to wander than wider blades. At 4 1/2" cut depth you are asking quite a bit of that little blade wanting it to stay plumb. If I had to guess I'd say the teeth on one side are sharper or out from center more causing it to pull. Can you use a wider blade like 1/4"? Some ability to do tight curves will be limited but it will be less likely to wander. If it worked fine before the blade change and you set it up the same I'd assume the blade you put on has a defect.

[Gissert]

I have the same saw(I love it), and the 1/8 blades will cut like that in stock that thick, more so on curves.

If you have a spindle sander, can you cut the pattern a little oversize, then square up the sides on the spindle?

[Tom7227]

Stop, rollers are OK, table is level. When I cut with a 1/8 inch blade on a decoy that was 5 inches wide I ended up 1/4 inch wider at the bottom of the cut. I put on a 3/16ths blade and was only wide 1/8 on a 4 inch cut. I put the tension on the blade to the point indicated on the back of the housing. I got burn marks on the material so obviously I am forcing it too much. Not sure if that's enough of a reason for the cuts not being straight. Sort of disappointing since the Grizzly is a good unit and not some $100 special at Harbor Freight.

[hydro]

Tom,

Don’t be disappointed with your Grizzly saw, it is working just fine. You mentioned that the guides have been set snug to the blade on the sides and back and are aligned with each other. I have been setting up band saws for a long time and if your guides and tension are properly set the problem you describe is 100% blade related.

Now look at the blade you are using. A 1/8” blade probably has a minimum of 14 teeth per inch, and you are trying to cut 4 ½” of wood. Each tooth needs to slice away material and carry it out through the bottom of the cut. With those tiny teeth, how fast do you think the gullets fill up with wood? You mentioned “burning” on the cut. What you are seeing is that the teeth fill up with wood near the top of the cut, then sort of slide through the rest of the way, not cutting much at all. The deflection at the bottom of the cut is caused by a plugged blade being forced through the wood.

To get a straight and clean cut through 4” material, use a blade with fewer teeth and more chip clearance. Grizzly makes a 3/16” 4 tooth/inch skip blade and a ¼” 4 tooth/inch hook blade that will do this for you. The skip tooth design has extra space between the teeth for chip clearance and a cutting angle for a smooth finish, and the 4 tooth hook design has both space and an aggressive tooth angle for fast cutting in thicker material. Also, with any blade, never push the work into the blade faster than the teeth can remove the chips. That builds heat and causes deflection in the cut.

[Tom7227]

Makes sense. I'll get additional blades and see how things work. Live and learn. Thanks for the info.

[PurpleFloyd]

Tom,

Don’t be disappointed with your Grizzly saw, it is working just fine. You mentioned that the guides have been set snug to the blade on the sides and back and are aligned with each other. I have been setting up band saws for a long time and if your guides and tension are properly set the problem you describe is 100% blade related.

Now look at the blade you are using. A 1/8” blade probably has a minimum of 14 teeth per inch, and you are trying to cut 4 ½” of wood. Each tooth needs to slice away material and carry it out through the bottom of the cut. With those tiny teeth, how fast do you think the gullets fill up with wood? You mentioned “burning” on the cut. What you are seeing is that the teeth fill up with wood near the top of the cut, then sort of slide through the rest of the way, not cutting much at all. The deflection at the bottom of the cut is caused by a plugged blade being forced through the wood.

To get a straight and clean cut through 4” material, use a blade with fewer teeth and more chip clearance. Grizzly makes a 3/16” 4 tooth/inch skip blade and a ¼” 4 tooth/inch hook blade that will do this for you. The skip tooth design has extra space between the teeth for chip clearance and a cutting angle for a smooth finish, and the 4 tooth hook design has both space and an aggressive tooth angle for fast cutting in thicker material. Also, with any blade, never push the work into the blade faster than the teeth can remove the chips. That builds heat and causes deflection in the cut.

+1

[jmd1]

also if you are weighting the blade to make it cut with more pressure, it might be cutting too fast causing heat to build up.