bandsaw cuts
07-10-2009, 09:50 PM
#3
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RE: bandsaw cuts
A fence for sure bit it's not as obvious as you'd think.
Every bandsaw has a bias angle that the blade wants to cut based on the position of the blade on the crown of the wheels and other factors. So you can't assume that a fence set to be parallel to the "front" of the table will cut true or as smootly as possible. Instead what you want to do is find the bias angle the blade of that blade and setup. To do this run a bigger piece through the saw such as a 2x2 with a line drawn along it. Push this piece through using nothing at all but pressure from a single finger at the end of the stick and centered on the line. Alter the direction of the stick until you have cut at least 5 to 6 inches directly on the line without the need to alter the angle of this fairly heavy, by model standards, stick. At that point shut off the saw and hold the stick firmly in place. Mark a line on the table along the stick to indicate the bias angle.
On my own model size bandsaw I made a fence that has clamping fingers at each end so that I can easily set the fence up parallel to this bias angle line. A fixed right angle rip fence on any bandsaw is a waste of time and material because of this bias angle. It needs to have the ability to set over a few degrees to this angle.
By using this method I have been able to not only cut model wood on occasion but to slice off "balogna" veneers of hardwood for making music instruments. I've used this method to recut both 6 and 8 inch slices of wood as little as 3/32 thick with no signs of cupping in the cuts.
Another thing you have to remember about bandsaws. Each time you replace the blade the side and back guides must be retracted, the blade running on the wheel crowns set and only then can the side guides and back rollers be brought in to an almost touching setting. If you don't do this there will be bowing tension in the blade and a short life and oddball cut results will be your lot in life.
Every bandsaw has a bias angle that the blade wants to cut based on the position of the blade on the crown of the wheels and other factors. So you can't assume that a fence set to be parallel to the "front" of the table will cut true or as smootly as possible. Instead what you want to do is find the bias angle the blade of that blade and setup. To do this run a bigger piece through the saw such as a 2x2 with a line drawn along it. Push this piece through using nothing at all but pressure from a single finger at the end of the stick and centered on the line. Alter the direction of the stick until you have cut at least 5 to 6 inches directly on the line without the need to alter the angle of this fairly heavy, by model standards, stick. At that point shut off the saw and hold the stick firmly in place. Mark a line on the table along the stick to indicate the bias angle.
On my own model size bandsaw I made a fence that has clamping fingers at each end so that I can easily set the fence up parallel to this bias angle line. A fixed right angle rip fence on any bandsaw is a waste of time and material because of this bias angle. It needs to have the ability to set over a few degrees to this angle.
By using this method I have been able to not only cut model wood on occasion but to slice off "balogna" veneers of hardwood for making music instruments. I've used this method to recut both 6 and 8 inch slices of wood as little as 3/32 thick with no signs of cupping in the cuts.
Another thing you have to remember about bandsaws. Each time you replace the blade the side and back guides must be retracted, the blade running on the wheel crowns set and only then can the side guides and back rollers be brought in to an almost touching setting. If you don't do this there will be bowing tension in the blade and a short life and oddball cut results will be your lot in life.
07-11-2009, 06:11 AM
#5
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RE: bandsaw cuts
ORIGINAL: BMatthews
A fence for sure bit it's not as obvious as you'd think.
Every bandsaw has a bias angle that the blade wants to cut based on the position of the blade on the crown of the wheels and other factors. So you can't assume that a fence set to be parallel to the ''front'' of the table will cut true or as smootly as possible. Instead what you want to do is find the bias angle the blade of that blade and setup. To do this run a bigger piece through the saw such as a 2x2 with a line drawn along it. Push this piece through using nothing at all but pressure from a single finger at the end of the stick and centered on the line. Alter the direction of the stick until you have cut at least 5 to 6 inches directly on the line without the need to alter the angle of this fairly heavy, by model standards, stick. At that point shut off the saw and hold the stick firmly in place. Mark a line on the table along the stick to indicate the bias angle.
On my own model size bandsaw I made a fence that has clamping fingers at each end so that I can easily set the fence up parallel to this bias angle line. A fixed right angle rip fence on any bandsaw is a waste of time and material because of this bias angle. It needs to have the ability to set over a few degrees to this angle.
By using this method I have been able to not only cut model wood on occasion but to slice off ''balogna'' veneers of hardwood for making music instruments. I've used this method to recut both 6 and 8 inch slices of wood as little as 3/32 thick with no signs of cupping in the cuts.
Another thing you have to remember about bandsaws. Each time you replace the blade the side and back guides must be retracted, the blade running on the wheel crowns set and only then can the side guides and back rollers be brought in to an almost touching setting. If you don't do this there will be bowing tension in the blade and a short life and oddball cut results will be your lot in life.
A fence for sure bit it's not as obvious as you'd think.
Every bandsaw has a bias angle that the blade wants to cut based on the position of the blade on the crown of the wheels and other factors. So you can't assume that a fence set to be parallel to the ''front'' of the table will cut true or as smootly as possible. Instead what you want to do is find the bias angle the blade of that blade and setup. To do this run a bigger piece through the saw such as a 2x2 with a line drawn along it. Push this piece through using nothing at all but pressure from a single finger at the end of the stick and centered on the line. Alter the direction of the stick until you have cut at least 5 to 6 inches directly on the line without the need to alter the angle of this fairly heavy, by model standards, stick. At that point shut off the saw and hold the stick firmly in place. Mark a line on the table along the stick to indicate the bias angle.
On my own model size bandsaw I made a fence that has clamping fingers at each end so that I can easily set the fence up parallel to this bias angle line. A fixed right angle rip fence on any bandsaw is a waste of time and material because of this bias angle. It needs to have the ability to set over a few degrees to this angle.
By using this method I have been able to not only cut model wood on occasion but to slice off ''balogna'' veneers of hardwood for making music instruments. I've used this method to recut both 6 and 8 inch slices of wood as little as 3/32 thick with no signs of cupping in the cuts.
Another thing you have to remember about bandsaws. Each time you replace the blade the side and back guides must be retracted, the blade running on the wheel crowns set and only then can the side guides and back rollers be brought in to an almost touching setting. If you don't do this there will be bowing tension in the blade and a short life and oddball cut results will be your lot in life.
07-11-2009, 10:18 AM
#6
Senior Member
RE: bandsaw cuts
B. Mathews has given you good advice. I have never had good success for ripping narrow strips with a band saw, no matter how diligent and carefully I set up the jigs. No substitute for a good table saw if you want to do a lot of ripping, especially of narrow strips. On my 10" table saw I can repeatedly cut as narrow as 1/16 inch square stock and make veneers so thin you can almost see through them.
07-11-2009, 08:02 PM
#8
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RE: bandsaw cuts
If your bandsaw isn producing cupped cuts then two things come to mind. First GET A NEW BLADE FROM A QUALITY MAKER! ! ! ! Cheap blades are sold straight from the shear and will not cut straight since the teeth are set but not ground so the burr left on the teeth produces a strong bias to one side.
Second you need to set the tension higher. A 1/4 inch blade when tensioned correctly should sing like the second up bass sting on a guitar or maybe more like the third up bass side string. That's a seriously musical note. Wider and thicker blades on bigger saws will vary but the point is that you need to ensure correct tension or your dead in the water before you even start. If you're using a cheap saw with cheezey plastic wheels that have no spring in the tensioning system then again you're stuck before you even start as such a saw will never accept the correct tension.
I've got one of the old bad rep 3 wheel saws. It has plastic wheels that don't run true. I modified the blade tensioner with a longer bolt that let me use a coil spring. In use I set the tension so it sort of goes "bongggggg" when I pluck the blade and the spring (thick coils) is strong enough to not flatten and coil bind but it allows enough "float" to deal with the wheel out of round issue so the blade doesn't see an excess tension. Before I was lucky to get 30 minutes of use from a blade. Now I can run it for more like2 to 3 hours. That's a lot of use if you think about it and don't go off to measure something with the saw running.
Second you need to set the tension higher. A 1/4 inch blade when tensioned correctly should sing like the second up bass sting on a guitar or maybe more like the third up bass side string. That's a seriously musical note. Wider and thicker blades on bigger saws will vary but the point is that you need to ensure correct tension or your dead in the water before you even start. If you're using a cheap saw with cheezey plastic wheels that have no spring in the tensioning system then again you're stuck before you even start as such a saw will never accept the correct tension.
I've got one of the old bad rep 3 wheel saws. It has plastic wheels that don't run true. I modified the blade tensioner with a longer bolt that let me use a coil spring. In use I set the tension so it sort of goes "bongggggg" when I pluck the blade and the spring (thick coils) is strong enough to not flatten and coil bind but it allows enough "float" to deal with the wheel out of round issue so the blade doesn't see an excess tension. Before I was lucky to get 30 minutes of use from a blade. Now I can run it for more like2 to 3 hours. That's a lot of use if you think about it and don't go off to measure something with the saw running.
07-12-2009, 06:37 PM
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RE: bandsaw cuts
I have a PDF of the now out of print
"The Band Saw Book"
I can Email it but your inbox must be able to take a 21 Meg file !!!
PM me if you want a copy
Johnkpap
"The Band Saw Book"
I can Email it but your inbox must be able to take a 21 Meg file !!!
PM me if you want a copy
Johnkpap
