If you study in detail the history of the use of band saws in the manufacture of furniture, it turns out that it began quite a long time ago.
If you study in detail the history of the use of band saws in furniture production, it turns out that it began quite a long time ago.
Nevertheless, such saws have been used in the production of pallet wood for only about two decades.
Sawing with band saws is constantly evolving and evolving.
What seemed impossible until recently has already been successfully used in wood processing.
Below, we will talk in more detail about band saws.
Band saws Such saws are used on different types of machines.
In particular, on mobile machines; on single-head machines; on multi-section machines.
The most common is considered to be a canvas with the following characteristics: thickness 0.9 mm and 1.1 mm; width 25, 31, 37 or 51 mm.
Most often, the canvas is made of high-tech carbon steel.
To increase the efficiency of its operation, different metal hardness is used, as well as a selective quenching area.
There are three main types of saws: a blade with a flexible back, but with hardened teeth, the back and teeth are hardened. The blade has the same hardness over the entire area. A blade with an equal degree of hardening over its entire area is called Constant Hardness.
The hardness of this type of saw is 45-48 HRC.
The peculiarity of Constant Hardness is that it has very good flexibility.
But due to the low carbon content in the steel composition, the canvas cannot have a high degree of hardening.
In general, there is initially a fairly good hardness and saws can be used in the processing of most types of wood.
When the hardened teeth are adjacent to the flexible back, this type of saw is called Nordex Flexble.
If you compare saws with the same hardness and this type, then the Nordex Flexble will have a higher carbon content.
The teeth of such a cloth are tempered not along the entire length, but only by half.
The hardness index is 63-65 HRC.
As for the base, its hardness is two times lower than that of the cutting edge (approximately 30-33 HRC).
This type of canvas can work for a very long time without sharpening.
These saws performed best on machines with small pulleys (diameter up to 750 mm).
A distinctive feature of such a canvas is a black line running along the teeth.
It appears after temperature treatment.
When hardening the back and teeth, the cloth is commonly called Hard Back.
The hardness of the teeth here is the same as that of the Nordex Flexble (63-65 HRC).
In this case, the cloth is not brought to such a high hardness, but after additional heat treatment it has indicators of 45-48 HRC.
Such manipulations are performed in order to make the back of the canvas more elastic.
The elasticity index increases by about 50%, which makes the canvas very attractive in terms of reliability and processing quality.
After double heat treatment, the canvas can be used with a very strong feed, and it will cope with all the proposed loads.
It was mentioned above that Nordex Flexble has a black stripe after temperature exposure.
It's the same here, only there are two stripes — along the back and along the teeth!
Carbon steel is not an essential attribute of a good canvas.
It can be successfully replaced with canvases made of high-speed steels, stellite or soldered with their alloys of increased hardness.
They are very technologically advanced, require more operations during production and the final cost of such canvases is much higher than their simpler counterparts.
In particular, due to the extremely low carbon content in their composition, they have excellent flexibility.
At the same time, the cutting ability of the blades is so good that the teeth retain sharpening for as long as possible.
It is not recommended to use such canvases in conventional wood processing.
Practice shows that Nordex canvases best justify themselves when used in special cases.
The downside of such saws is the expense item.
Ideally, the canvas should work until it is blunted, in which case the use of such expensive saws is justified from a financial point of view.
But if for some reason the canvas has become unusable until the moment of blunting, then it becomes not profitable to use it!
09 Martha 2017
