SawingSawingBasicsBasics

When making blade recommendations, there are a few questions we need to answer:

What Blade Do We Use?What Blade Do We Use? What Tooth Pitch Do We Use?What Tooth Pitch Do We Use? What Blade Speed Should We Use?What Blade Speed Should We Use? What Feed Rate Should We Use?What Feed Rate Should We Use? - The Relationship Between Feed & SpeedThe Relationship Between Feed & Speed Why Do We Need A Cutting Fluid?Why Do We Need A Cutting Fluid? Why Do We Need Blade Break-In?Why Do We Need Blade Break-In?

What Blade Do We Use?Items That Influence Selection

Machine TypeMachine Type - Low cost, low performance machines will - Low cost, low performance machines will not allow a band saw blade to function optimally not allow a band saw blade to function optimally

• for low performance machines, select blades that can take for low performance machines, select blades that can take chatter or vibrationchatter or vibration

• the better the feed system on a machine, the higher the blade the better the feed system on a machine, the higher the blade

quality that can be used effectivelyquality that can be used effectively

Production RateProduction Rate - The higher the number of cuts per hour - The higher the number of cuts per hour or the longer the run time the better the quality of the or the longer the run time the better the quality of the blade will need to beblade will need to be

Cost Per CutCost Per Cut - to lower the cost per cut, move to a better - to lower the cost per cut, move to a better quality bladequality blade

What Blade Do We Use?Items That Influence Selection

Material MachinabilityMaterial Machinability - Alloy type, hardness and shape all - Alloy type, hardness and shape all affect material machinabilityaffect material machinability

• The higher the alloy, the lower the machinability ratingThe higher the alloy, the lower the machinability rating• The higher the material hardness, the lower the machinability The higher the material hardness, the lower the machinability

ratingrating• Complex material shapes will lower the machinability ratingComplex material shapes will lower the machinability rating

AbrasivenessAbrasiveness - Abrasive material or coatings will reduce - Abrasive material or coatings will reduce the life of a band saw blade – consider carbide tipped the life of a band saw blade – consider carbide tipped blades or carbide grit edge bladesblades or carbide grit edge blades

MachinabilityMachinability is generally rated from 0 to 100%is generally rated from 0 to 100%

(SAE1112, rated at 100%, is considered free cutting)(SAE1112, rated at 100%, is considered free cutting)

What Blade Do We Use?

CarbonCarbon• Duratec FB- Economical cutting of easy-to-machine ferrous or non-- Economical cutting of easy-to-machine ferrous or non-

ferrous metals and wood.ferrous metals and wood.

• Duratec PH - Greater rigidity than Duratec FB for more accurate, - Greater rigidity than Duratec FB for more accurate, straighter cuts. Economical production cutting.straighter cuts. Economical production cutting.

BiMetalBiMetal• Intenss PRO – Triple tempered M-42 edge with 8% cobalt bonded – Triple tempered M-42 edge with 8% cobalt bonded

to a fatigue resistant alloy backing that features up to a 12 degree to a fatigue resistant alloy backing that features up to a 12 degree positive rake This allows for easier penetration, faster, straighter positive rake This allows for easier penetration, faster, straighter cuts and improved surface finish. For high production cutting of cuts and improved surface finish. For high production cutting of nickel based and non-ferrous alloys in solids, tubing, structurals and nickel based and non-ferrous alloys in solids, tubing, structurals and bundles.bundles.

• Intenss PRO VTH - Same construction as our Intenss PRO blade - Same construction as our Intenss PRO blade but with varying tooth heights. This creates a surging cutting action but with varying tooth heights. This creates a surging cutting action to aid in penetration of large sections of exotic and nickel-based to aid in penetration of large sections of exotic and nickel-based alloys and high hardness steels.alloys and high hardness steels.

• Versatix- Excellent general purpose blade for all machines. Special set tooth design minimizes pinching when cutting structurals and set tooth design minimizes pinching when cutting structurals and bundles. Less tooth breakage and longer blade life.bundles. Less tooth breakage and longer blade life.

• Die Pro - Bi-Metal Unique construction, available in 1/4” thru 1/2” - Bi-Metal Unique construction, available in 1/4” thru 1/2” widths, constant and variable pitches. For general purpose cutting widths, constant and variable pitches. For general purpose cutting of tool, die and mold steels, stainless steels, abrasive exotic alloys, of tool, die and mold steels, stainless steels, abrasive exotic alloys, structurals, tubing and solids.structurals, tubing and solids.

What Blade Do We Use?

Carbide TippedCarbide Tipped

• Advanz FS - Features a carbide cylinder, selected for it’s - Features a carbide cylinder, selected for it’s toughness, shock and wear resistance, providing faster, smoother toughness, shock and wear resistance, providing faster, smoother cutting on a variety of abrasive materials. Aluminum Castings, cutting on a variety of abrasive materials. Aluminum Castings, Fiberglass, Masonite, Plastics, Composites, and Abrasive Wood. Fiberglass, Masonite, Plastics, Composites, and Abrasive Wood.

• Advanz TS – Features Micro-grain Carbide for cutting High-Alloy – Features Micro-grain Carbide for cutting High-Alloy metals, Difficult to machine steels, Titanuim, Stainless Steel, Inconel metals, Difficult to machine steels, Titanuim, Stainless Steel, Inconel and for high production applications.and for high production applications.

• Advanz CG - Tungsten Carbide grit bonded to an alloy backing. Tungsten Carbide grit bonded to an alloy backing. Easily cuts fiber reinforces plastics, Graphite composites, carbon, Easily cuts fiber reinforces plastics, Graphite composites, carbon, Glass, Steel belted tires and case hardened steels.Glass, Steel belted tires and case hardened steels.

• Advanz DG - If Carbide Grit won’t cut it, Diamond Grit is If Carbide Grit won’t cut it, Diamond Grit is recommended.recommended.

What Tooth Pitch Do We Use?Number Of Teeth In The Cut

MinimumMinimum - 3 teeth in the cut - 3 teeth in the cut If there are too few teeth in the cut, the teeth can straddle the If there are too few teeth in the cut, the teeth can straddle the

workpiece, which can cause tooth strippageworkpiece, which can cause tooth strippage

MaximumMaximum - 24 teeth in the cut - 24 teeth in the cut too many teeth in the cut may cause the gullets to “overload”, too many teeth in the cut may cause the gullets to “overload”,

because there is not enough gullet capacity to hold all the chips - because there is not enough gullet capacity to hold all the chips - this can cause blade bouncing and tooth strippagethis can cause blade bouncing and tooth strippage

The “Optimum” is 6 to 12 teeth in cut at any timeThe “Optimum” is 6 to 12 teeth in cut at any time

What Tooth Pitch Do We Use?Number Of Teeth In The Cut

ConditionsConditions that influence pitch selection: that influence pitch selection:

• soft materials require fewer teeth and more gullet capacitysoft materials require fewer teeth and more gullet capacity

• hard materials require more teeth to share in the work and less hard materials require more teeth to share in the work and less gullet areagullet area

• machine capabilities - constant feed machines can use a coarser machine capabilities - constant feed machines can use a coarser pitch, whereas gravity feed machines will require a finer pitchpitch, whereas gravity feed machines will require a finer pitch

• production vs. finish or blade lifeproduction vs. finish or blade life for production cutting, run on the coarse end of the spectrumfor production cutting, run on the coarse end of the spectrum for good cut finish, run on the fine end of the spectrumfor good cut finish, run on the fine end of the spectrum for blade life, run in the middle to the fine end of the spectrumfor blade life, run in the middle to the fine end of the spectrum

1112Carbon

Soft

3 Teeth

D-2, Die SteelsHard

18 Teeth

718InconelTough

12 Teeth

What Tooth Pitch Do We Use?Optimizing Tooth Pitch

A General Rule of Thumb . . .A General Rule of Thumb . . .

Soft Materials – Soft Materials – use fewer teeth in the cut – in the 3 to 6 tooth rangeuse fewer teeth in the cut – in the 3 to 6 tooth range• Aluminum, Copper, Bronze, Carbon SteelsAluminum, Copper, Bronze, Carbon Steels

Hard Materials – Hard Materials – use more teeth in the cut – in the 18 to 24 tooth rangeuse more teeth in the cut – in the 18 to 24 tooth range• D-2, Die Steels, Stainless SteelsD-2, Die Steels, Stainless Steels

Tough Materials – Tough Materials – use a moderate amount of teeth in the cut – in the 12 to 18 use a moderate amount of teeth in the cut – in the 12 to 18 tooth rangetooth range• Inconel, Hastalloy, Waspalloy, MonelInconel, Hastalloy, Waspalloy, Monel

What Tooth Pitch Do We Use?Optimizing Tooth Pitch

To Determine the Number of Teeth in a Cut with Variable Pitch Band To Determine the Number of Teeth in a Cut with Variable Pitch Band Saw Blades, we need to take the Average of the Pitch:Saw Blades, we need to take the Average of the Pitch:

PitchPitch AverageAverage 3 - 4 Pitch3 - 4 Pitch 3 1/2 TPI3 1/2 TPI4 - 6 Pitch4 - 6 Pitch 5 TPI5 TPI5 - 8 Pitch5 - 8 Pitch 6 1/2 TPI6 1/2 TPI6 -10 Pitch6 -10 Pitch 8 TPI8 TPI

10 -14 Pitch10 -14 Pitch 12 TPI 12 TPI

Example: Calculate the Number of Teeth in the Cut in 4" Bar Stock, Example: Calculate the Number of Teeth in the Cut in 4" Bar Stock, using a 3-4 Variable Pitch Bladeusing a 3-4 Variable Pitch Blade

Bar Stock Size x Avg TPI = # of Teeth in the Cut (4 x 3.5 = 14)Bar Stock Size x Avg TPI = # of Teeth in the Cut (4 x 3.5 = 14)

a 2-3 Variable Pitch blade would have 10 teeth in the cuta 2-3 Variable Pitch blade would have 10 teeth in the cut

a 4-6 Variable Pitch blade would have 20 teeth in the cuta 4-6 Variable Pitch blade would have 20 teeth in the cut

a 6-10 Variable Pitch blade would have 32 teeth in the cuta 6-10 Variable Pitch blade would have 32 teeth in the cut

What Blade Speed Should We Use?Items That Influence SelectionItems That Influence Selection

Material Machinability Rating - The lower the rating %, the slower the Material Machinability Rating - The lower the rating %, the slower the band speed will need to beband speed will need to be

Blade Selection - The cutting edge of the blade will govern the speed the Blade Selection - The cutting edge of the blade will govern the speed the blade can run at (Carbon = Slowest Cutting, Carbide = Fastest Cutting)blade can run at (Carbon = Slowest Cutting, Carbide = Fastest Cutting)

Cutting Noise / Vibration - Cutting noise or vibration is a killer to a cutting Cutting Noise / Vibration - Cutting noise or vibration is a killer to a cutting edge - if either is present, the speed must be edge - if either is present, the speed must be decreaseddecreased

Coolant / Cutting Fluid - If the coolant is adequate, use the standard Coolant / Cutting Fluid - If the coolant is adequate, use the standard cutting chart speeds. When cutting dry, reduce the speed by 40-50%cutting chart speeds. When cutting dry, reduce the speed by 40-50%

Cutting Speed TerminologyCutting Speed Terminology

What Blade Speed Should We Use?Items That Influence Selection

Remember, when considering blade speed, consider the saw . . . if the saw Remember, when considering blade speed, consider the saw . . . if the saw has limited or no ability to adjust speed, you must work with what you has limited or no ability to adjust speed, you must work with what you have!have!

A General Rule of Thumb . . .A General Rule of Thumb . . .

100 – 200 – 300100 – 200 – 300

Hard Materials – set the blade speed for 100 S.F.P.M. to start . . .Hard Materials – set the blade speed for 100 S.F.P.M. to start . . . Medium Materials – set the blade speed for 200 S.F.P.M. to start . . .Medium Materials – set the blade speed for 200 S.F.P.M. to start . . . Soft Materials – set the blade speed for 300 S.F.P.M. to start . . .Soft Materials – set the blade speed for 300 S.F.P.M. to start . . .

. . . Then adjust the speed as needed to get the required result!. . . Then adjust the speed as needed to get the required result!

Cutting Speed TerminologyCutting Speed Terminology

What Feed Rate Should We Use?Items That Influence SelectionItems That Influence Selection

Material Machinability Rating - The lower the rating %, the slower the cutting Material Machinability Rating - The lower the rating %, the slower the cutting rate will need to be.rate will need to be.

Blade Selection - The cutting edge of the blade will govern the rate the blade can Blade Selection - The cutting edge of the blade will govern the rate the blade can cut at (Carbon = Slowest Cutting, Carbide = Fastest Cutting)cut at (Carbon = Slowest Cutting, Carbide = Fastest Cutting)

Cutting Noise / Vibration - Cutting noise or vibration are killers to a cutting edge - if Cutting Noise / Vibration - Cutting noise or vibration are killers to a cutting edge - if present, the blade speed must be present, the blade speed must be decreaseddecreased or feed rate must be or feed rate must be increasedincreased

Coolant / Cutting Fluid - If the coolant is adequate, use the standard cutting chart Coolant / Cutting Fluid - If the coolant is adequate, use the standard cutting chart rates. When cutting dry, reduce the feed by 50 to 75%rates. When cutting dry, reduce the feed by 50 to 75%

Cutting Rate TerminologyCutting Rate Terminology

What Feed Rate Should We Use?Items That Influence SelectionItems That Influence Selection

Chip Formations:Chip Formations:

Light chips cause short blade lifeLight chips cause short blade life• heat from rubbing, not cutting, will work-harden some heat from rubbing, not cutting, will work-harden some

materials and dull the cutting edgematerials and dull the cutting edge

Chips formed when the blade is cutting correctly have a Chips formed when the blade is cutting correctly have a bright metallic colorbright metallic color

Chips formed when the blade is over feeding have a Chips formed when the blade is over feeding have a heavy thick tan or blue color (Stainless steel will not heavy thick tan or blue color (Stainless steel will not change color)change color)

The Relationship Between Feed & Speed What’s the relationship between feed, speed & tooth pitch?What’s the relationship between feed, speed & tooth pitch?

Speed & Feed are directly relatedSpeed & Feed are directly related – if you – if you want to change the cut result, then change want to change the cut result, then change only one variable (speed or feed) at a time:only one variable (speed or feed) at a time:

IncreasingIncreasing the the Work SizeWork Size will will decreasedecrease tooth penetration. tooth penetration.

ReducingReducing the the Tooth PitchTooth Pitch will will increaseincrease tooth penetration. tooth penetration.

IncreasingIncreasing the the Tooth PitchTooth Pitch will will decreasedecrease tooth penetration. tooth penetration.

IncreasingIncreasing the the Blade SpeedBlade Speed will will decreasedecrease tooth penetration. tooth penetration.

ReducingReducing the the Blade SpeedBlade Speed will will increaseincrease tooth penetration. tooth penetration.

The Relationship Between Feed & Speed What’s the relationship between feed, speed & tooth pitch?

ExampleExample: 1” solid work piece: 1” solid work piece 100 lbs, feed pressure on the blade100 lbs, feed pressure on the blade

Blade #1Blade #12 T.P.I. equals 50 lbs. per tooth penetration2 T.P.I. equals 50 lbs. per tooth penetration

Blade #2Blade #210 T.P.I. equals 10 lbs. per tooth penetration10 T.P.I. equals 10 lbs. per tooth penetration

Why Do We Need A Cutting Fluid?

Lubricating the cutting edge will reduce the heat that is generated by cutting friction - too much heat in the cut is one of the main reasons for blade failure

• A flood of coolant helps wash the chips from the gulletsA flood of coolant helps wash the chips from the gullets Chips become work-hardened in the cutting operationChips become work-hardened in the cutting operation If chips are dragged back through the cut a second time, If chips are dragged back through the cut a second time,

they can damage teeththey can damage teeth

• A flood of coolant helps cool the blade's cutting edge and saw A flood of coolant helps cool the blade's cutting edge and saw guidesguides

Remember, flood coolant whenever possible, and . . .

. . . Only use coolant where chips are present – never use coolant on materials that produce powdered chips, such as gray iron.

Why Do We Need Blade Break-In?

New, sharp teeth are more fragile than lightly honed teethNew, sharp teeth are more fragile than lightly honed teeth Break-in hones the teeth and helps make all teeth the same heightBreak-in hones the teeth and helps make all teeth the same height Proper break-in results in less blade strippage and longer blade lifeProper break-in results in less blade strippage and longer blade life

Break-in Procedure:Break-in Procedure:

1.1. Set proper blade speed for the machinability and size of material to be cutSet proper blade speed for the machinability and size of material to be cut

2.2. Reduce the normal feed rate by approximately 50% of the regular rate for the first Reduce the normal feed rate by approximately 50% of the regular rate for the first few cuts or 50-100 square inches.few cuts or 50-100 square inches.

3.3. Watch the chips!!!Watch the chips!!!• Small flakes --------------Insufficient feedSmall flakes --------------Insufficient feed• Heavy blue chips --------Excessive feedHeavy blue chips --------Excessive feed• Spring curled no color - Proper feed rateSpring curled no color - Proper feed rate

--- --- During break-in, it is important that the band always produce chipsDuring break-in, it is important that the band always produce chips --- ---AVOID VIBRATIONAVOID VIBRATION

4.4. At the end of the Break in cuts, increase the feed rate to 100%At the end of the Break in cuts, increase the feed rate to 100%

Why Do We Need Blade Break-In?

Helpful HintsHelpful Hints• Always recheck the tension after making a few cutsAlways recheck the tension after making a few cuts

• Never start a blade into an old cutNever start a blade into an old cut

• Do not stop a blade in the cut without first stopping the feedDo not stop a blade in the cut without first stopping the feed

Proper Break-in can increase blade life greatlyProper Break-in can increase blade life greatly• If the user doesn’t currently break-in blades, try to encourage them to, If the user doesn’t currently break-in blades, try to encourage them to,

use increased blade life as the benefit use increased blade life as the benefit

• If you can get them to do any sort of break-in, If you can get them to do any sort of break-in, even if its not to the even if its not to the procedure on the preceding slide,procedure on the preceding slide, some break-in is better than no some break-in is better than no break-in at all for blade lifebreak-in at all for blade life

Variables That Require AttentionVariables That Require Attention

The Right Blade for the JobThe Right Blade for the Job Tooth Pitch – Number of Teeth In The CutTooth Pitch – Number of Teeth In The Cut

Blade SpeedBlade Speed Feed RateFeed Rate

Cutting FluidCutting Fluid Blade Break-InBlade Break-In

When everything is right, a band saw blade will When everything is right, a band saw blade will cut lots of good quality parts, consistently!!cut lots of good quality parts, consistently!!