FOR TURN SCREW AND SPRING TENSIONING MACHINES
1. Remove guides–you CANNOT run this test if the band saw blade is restricted in any lateral movement.
2. Make sure tire surfaces are in good condition–they cannot be hard, flattened out, cracked or brittle. On mills with loose fitting V-belts, replace them with the next size down so they are tight fitting. This will eliminate over 80% of the vibration in your mill and the blade.
3. Mount the blade on the machine and apply the tension to the band that the manufacturer recommends for other steels.
4. Close all covers for safety purposes.
5. Start the machine, engage the clutch into the high speed cutting mode. NOTE: You will not be cutting any wood.
6. Stand at the head of the machine, with your hand on the turn screw tensioner and your eyes on the band saw blade. Very slowly start detensioning by half turns at a time, keeping your eyes on the band saw blade. The object is to bring the tension of the blade down to a point that the blade starts to flutter. TAKE YOUR TIME.
7. When you see the band start to flutter, you have hit ground “ZERO”. Now start ADDING quarter turns of tension, SLOWLY, until the band stops fluttering and is running stable again. At this point ADD one-eight to one-quarter turn of tension.
8. You have now tensioned our blade correctly. Shut off the machine and put your guides back in place. You are now ready to start sawing.
9. ALWAYS DETENSION YOUR BAND SAW BLADES. Since you do not know exactly where the proper tension is, it will be easier to remember if you take off 8, 9, or 10 full turns of tension until the band is completely relaxed. The next time you use our bands, add the same amount of turns of tension that were taken off. At this point, you will only have to run the flutter test one time.
FOR HYDRAULIC TENSION
Run the same test as above. With hydraulic tension you need to detension 20-25 lbs. at a time. After you have removed the flutter, add an extra 50 lbs. of pressure. Remember the pressure on your gauge.
ALWAYS DETENSION YOUR BAND SAW BLADES. The next time you use our band, tension it to the same setting you found after running the flutter test.
FOR AIR BAG TENSION
Run the same test as above. With air bag tension, you need to detension 15 lbs. at a time. After you have removed the flutter, add an extra 15 lbs. of pressure. With the air bag tension you usually have a gauge and you will know exactly where low tension is by reading the gauge. ALWAYS DETENSION YOUR BAND SAW BLADES. The next time you use our band, tension it to the same setting you found after running the flutter test.
WARNING: IF YOU DO NOT RUN THE FLUTTER TEST ON OUR SPECIAL SILICON STEEL BLADES, YOU WILL NOT ACHIEVE THE ENDURANCE AND LONGEVITY THAT OUR HIGH DUCTILE BANDS ARE CAPABLE OF.
CHOOSING THE PROPER BAND SAW BLADE LUBRICATION
NEVER USE WATER as a lubricant on band saw blades. Water is NOT a lubricant and is the WRONG thing to use for many reasons.
1. For the woodworker using 1″ and 1 1/4″ bands, not only is water unacceptable as a lubricant, but it also rusts the bands causing deep pitting, and inappropriate chip swelling. This prematurely destroys the body of the band and its gullets. It also dry rots your tires or V-belts.
For proper lubrication mix HIGH ADHESION CHAIN SAW BAR OIL, with 50% kerosene or diesel fuel. Apply the solution with a spray bottle to BOTH sides of the band about once every four minutes, while the machine is running. When this lubrication is applied, the sound of cutting decreases over 50%. DO NOT APPLY AGAIN until the sound of cutting starts increasing. I guarantee you will be amazed! Longer life; No pitch buildup; No rusted or pitted bands! A great delivery system is the 12 volt windshield washer assembly out of an old car!
2. “Pam” spray-on vegetable shortening is a great lubrication for 3/4″ WIDTH AND UNDER band saw blades on vertical saws. (EXAMPLE: Delta, Grizzly, Jet, etc.) Unplug the machine. Spray Pam vegetable shortening on a rag and wipe on both sides of the blade while turning the upper wheel by hand. You will hear a 50% sound reduction when cutting.
A band saw blade is a tool. You must lubricate both sides!
In both cases, we know for a fact that lubrication of the body of the band increases band life by over 30%. Applied sparingly, you can cut grade lumber with NO staining to your product.
ALWAYS DETENSION YOUR BANDS
When you are done cutting for the day, take the tension off your blade. Band saw blades, when warmed up from cutting, always stretch; and upon cooling shrink by tens of thousandths of an inch each cooling period. Therefore, blades, when left on the saw over tension themselves and leave the memory of the two wheels in the steel of the band, which will cause cracking in the gullet. When you leave the band on your saw under tension, not only do you distort the crown and flatten out the tires (which makes them very hard), but you also place undue stress on your bearings and shafts. Believe it or not; you can, and will damage your wheel geometry sooner or later and considerably shorten bearing life. You are also crushing your tires or V-belts.
WHAT IS APPROPRIATE SET?
Appropriate set is when you have a mixture of 65%-70% saw dust and 30%-35% air in the space between the body of the band and the wood you are cutting. The SIGN you are looking for, when you are running appropriate set, IS A GOOD 80%-85% SAW DUST EJECTION FROM THE CUT! If you are running too much set for the mass or thickness of the wood, you have too much air and not enough saw dust. You will leave EXCESSIVE loose saw dust and most likely it will be accompanied by tooth marks. If you are running under set, you will have no air flow pulling the saw dust out…The SIGN for this is excessive HOT packed down saw dust. This is the most damaging thing you can do to a band. You will have short cutting times and premature band breakage. The saw dust should be warm to the touch, not hot or cold. One last thing, a band that is excessively under set will cut in a wavy motion, and a band that has an improper HOOK ANGLE and is UNDER SET will cut a bow across the board every time! See “TROUBLE SHOOTING”.
WHAT IS HOOK ARTICULATION?
Because of our deep gullets, we are able to use lower hook angles which generate less heat on the tip of the tooth. The Timber Wolf® series of bands uses a 10 degree rake or hook angle which is capable of penetrating most surfaces from medium-hard to medium-soft woods.
If you are cutting very hard wood like white oak, walnut, ash or anything frozen throughout, the blade will probably rise in the cut. This is called push-off. The hook angle must be brought back to 8 degrees. You will notice as the angle goes from 10 degrees to 8 degrees, the tooth becomes more perpendicular, thus INCREASING its penetration factor.
As the tip of the tooth goes from 10 degrees to 12 degrees the tip of the tooth starts pointing forward DECREASING penetration in hardwood. If you use 8 degrees on soft wood the blade may chatter because it’s over feeding itself, unless it’s very knotty. You need to use an 8 degree hook angle for hard knots. On the other hand, if you use a 12 degree hook angle on very hard wood, the tooth skips over the hard surface because the tip of the tooth is pointing too far forward.
Having a 12 degree hook angle in hardwood cutting causes push-off making the band ride up. The band locks itself in place, cuts straight across, and drops down at the end of the cut. This also burns up the band and over tensions it.
By articulating the proper hook angle, and having your gullet mathematically correct for the pitch, you will achieve straight grade cuts every time. YOU MUST UNDERSTAND APPROPRIATE SET AND HOOK ARTICULATION, THEY WORK TOGETHER. We manufacture for North America 5 appropriate sets with a 10 degree hook angle. 70% of the time this hook angle will be perfect for whatever you are cutting. See “TROUBLE SHOOTING”.
WARNING: Again just as I have brought to your attention the short life of a dial indicator, you are also trusting the templates and gauges on your band saw blade sharpeners. They are hardly set at the exact angle that you think they are. The machines themselves wear out. The pins and the guides in the sharpener that the back of the band rides on, wear out. If a band starts riding on an angle a few degrees and you are unable to see it, you will know there’s something wrong after running that resharpened band. To give you an idea of the amount of wear your sharpener will receive, think of this. Your band, if 14 ft. long, will travel around your sharpener a minimum of twice during each sharpening. You have sharpened 50 bands. 50 x 14 ft. twice or 28 ft. = 1,400 ft. or over a 1/4 of a mile with the back of the bands rubbing on the alignment pins and wearing them out. How do you determine if your hook angle is right, and see it. Simple: THERE IS A TOOL FEW OF YOU HAVE. There is a specific tool made especially to measure your hook angle and that’s a PROTRACTOR. You must have a specific TYPE OF PROTRACTOR. Without it, you are blind and will never be able to articulate a band saw blade. Without a protractor, you are assuming the hook angles are right. I have analyzed over 4,000 band saw blades since 1992. Over half of the problems, were due to assuming the hook angle was right on. We have in stock precision Starrett® band saw blade protractors, at our cost. You must have one. It’s mandatory!
GULLET PROCEDURE SHARPENING
THERE IS ONLY ONE WAY TO SHARPEN A BAND SAW BLADE. A stone must come down the face of the tooth, around the bottom of the gullet and up the back side of the tooth in ONE SWEEPING ACTION. You MUST maintain gullet integrity.
The gullet is NOT a trash can or dumpster for the saw dust. In fact, it is the second hardest working part of the band. A well defined gullet is like the inverted wing of an aircraft. It is responsible for the forced air flow, cooling the steel and removal of the saw dust.
If you are running appropriate set, the air is driven through the log by the gullet at the speed of the band. This causes the saw dust to be sucked out of the cut. The saw dust effectively cools the gullet by spinning around the inside and spilling over the back side of the next tooth. You MUST maintain a 40% gullet fill for proper cooling and extended cutting time.
If you sharpen just the face and the back side of the tooth, you ruin the gullet integrity and destroy the performance of the band.
THERE ARE 4 PARTS TO A BAND SAW BLADE AND THE IMPORTANCE OF EACH PART IS:
1. THE STEEL – The steel is the hardest working part. Less expensive brittle steel not only welds harder but must be highly tensioned, thus decreasing overall run time no matter what you do.
2. THE GULLET – The gullet is the second hardest working part of the band. It is the highway for proper air flow, causing the cooling of the band and chip removal.
3. THE TIP OF THE TOOTH – The tip of the tooth is the third most important, and we all know what that does. By the way, always keep a 10 degree hook angle. NO more, NO less for good general sawing. Very hard, frozen or knotty wood uses an 8 degree hook angle. See”HOOK ARTICULATION #5″.
4. THE SET & HOOK ANGLE – These valves bring the whole science of band saw blade physics and the ART of sawing together. On our videotape, there is a 40 minute segment dedicated on how to correctly sharpen a bandsaw blade and also how to build, out of a 5″ or 6″ bench grinder, a manual gullet procedure sharpener. We include a schematic. See”TROUBLESHOOTING”.
When all is said and done, the band saw, in all its shapes and sizes, is a fundamental machine. But, as you have just read, there is a lot to know in becoming the master of your machine. “The Sawyer.”
“The minimum amount of STRETCH you must apply to the body of the band to make it stable.” Always DETENSION the band immediately after use.