A Full Review Of The Electric Power Saw
The principal factor determining the size of the saw is the diameter of the blade.
Allied extremely closely to this is the depth of cut.
This is the amount of the blade that projects from the sole plate of the tool and gives the maximum thickness of wood that can be cut.
As with other power tools, the wattage of the motor is related to its power, and with a saw, it is particularly beneficial for this to be adequate for the sawing to proceed at a reasonable speed when cutting at full depth in both hardwoods and softwoods.
The rpm of the blade is a factor in both overall cutting efficiency and speed of sawing, although the rpm is a direct contrast to the size of the blade.
The critical speed of the saw is the speed at the periphery that is the speed at which the teeth pass through the wood.
The optimum speed for a circular saw is a peripheral rate of 9,000 feet per minute, or around 2,750 metres per minute.
Thus for a blade with a diameter of 200mm, which has a circumference of around 630mm, the speed should ideally be in the region of 4,300rpm.
All these figures are approximate, and circular saws, small ones especially, will operate quite well at a speed much lower than the optimum.
Little is achieved by having the blade rotating excessively fast, but if it is far too low then a slow rate of feed through the wood does not quite compensate for this.
Remember with portable power saws in particular there will be a drop in speed when the saw is operating under full load.
The saw blade, and especially the tooth size and form, vary considerably.
The vast majority of saw blades in use at the present time has TCT teeth and, this includes most of those fitted to portable saws.
The alternative to this is the traditional one usually known as a plate steele blade.
Tungsten carbide is exceptionally hard and has a working life between sharpenings of between twenty, and fifty times that of a plate steel blade.
In addition, a TCT blade gives a highly accurate and smooth cut, although this is dependent on tooth size and form, the diameter of the blade and other factors including, of course, the quality of the tool itself.
However, there is a price to pay for TCT blades.
Their initial cost is quite high, and the tungsten is so hard that it requires equipment to sharpen the blades, requiring them to be sent away for attention when blunt.
In addition, like most materials that are particularly hard, tungsten is brittle.
This means that if a blade hits a foreign body in the wood, and particularly if the object itself is hard and is struck fairly suddenly, one or more of the tips can become chipped or even wrenched from the body of the tooth.
Saw specialists can repair damaged blades by brazing new tips in place.
While TCT blades are in no way intended for cutting mild steel, if a nail is accidentally hit while cutting a piece of wood then the blunting effect is most likely to be far less than it would be for a plate steel blade.
The blades fitted to most portable saws have the tooth pattern known as universal.
This means that its shape and the way in which it is sharpened are designed for cutting both across and along the grain.
Allied extremely closely to this is the depth of cut.
This is the amount of the blade that projects from the sole plate of the tool and gives the maximum thickness of wood that can be cut.
As with other power tools, the wattage of the motor is related to its power, and with a saw, it is particularly beneficial for this to be adequate for the sawing to proceed at a reasonable speed when cutting at full depth in both hardwoods and softwoods.
The rpm of the blade is a factor in both overall cutting efficiency and speed of sawing, although the rpm is a direct contrast to the size of the blade.
The critical speed of the saw is the speed at the periphery that is the speed at which the teeth pass through the wood.
The optimum speed for a circular saw is a peripheral rate of 9,000 feet per minute, or around 2,750 metres per minute.
Thus for a blade with a diameter of 200mm, which has a circumference of around 630mm, the speed should ideally be in the region of 4,300rpm.
All these figures are approximate, and circular saws, small ones especially, will operate quite well at a speed much lower than the optimum.
Little is achieved by having the blade rotating excessively fast, but if it is far too low then a slow rate of feed through the wood does not quite compensate for this.
Remember with portable power saws in particular there will be a drop in speed when the saw is operating under full load.
The saw blade, and especially the tooth size and form, vary considerably.
The vast majority of saw blades in use at the present time has TCT teeth and, this includes most of those fitted to portable saws.
The alternative to this is the traditional one usually known as a plate steele blade.
Tungsten carbide is exceptionally hard and has a working life between sharpenings of between twenty, and fifty times that of a plate steel blade.
In addition, a TCT blade gives a highly accurate and smooth cut, although this is dependent on tooth size and form, the diameter of the blade and other factors including, of course, the quality of the tool itself.
However, there is a price to pay for TCT blades.
Their initial cost is quite high, and the tungsten is so hard that it requires equipment to sharpen the blades, requiring them to be sent away for attention when blunt.
In addition, like most materials that are particularly hard, tungsten is brittle.
This means that if a blade hits a foreign body in the wood, and particularly if the object itself is hard and is struck fairly suddenly, one or more of the tips can become chipped or even wrenched from the body of the tooth.
Saw specialists can repair damaged blades by brazing new tips in place.
While TCT blades are in no way intended for cutting mild steel, if a nail is accidentally hit while cutting a piece of wood then the blunting effect is most likely to be far less than it would be for a plate steel blade.
The blades fitted to most portable saws have the tooth pattern known as universal.
This means that its shape and the way in which it is sharpened are designed for cutting both across and along the grain.
Source...