Previously, it was said about the method of sharpening band saws.
At the same time, the practical side of this operation is somewhat controversial due to the rather high economic and time losses.
Quite a lot of owners of band saws consider the cost of one cut, expecting that the canvas will not overflow and will not be thrown away after work.
Others are trying to reduce the cost of equipment and apply re-sharpening of the canvas.
There are two fundamental rules related to reducing the price of the tool – "sharpeners" and "non-sharpeners".
Firstly, it depends on the loss of physical force that you apply.
The first test is that the canvases will work as long as they can, changing the canvas only when it becomes too dull or there is a possibility of a breakage or fatigue of the canvas.
Using this method, you do not need to monitor the safety of the tool, because downtime occurs, which is very expensive.
New canvases that are well welded and properly handled will be in fairly good condition.
This will allow you to replace the canvases after a certain period, and you will be able to reduce downtime, as well as the time to change the canvas.
Unplanned downtime is the main problem that occurs when rewinding ribbon webs – it can quickly negate the condition, due to the slow work of the staff to change the canvas.
If you do not use rewinding of the canvas, then the key to success will be the use of high-quality canvases with a very high degree of durability and a low purchase price.
The second test is the re–sharpening of band saws.
If done correctly, this is a very cost-effective way to extend the life of the ribbon webs.
Two general rules apply in choosing the type of tape webs used (re-sharpening or without it): Funds for technical condition and losses for physical strength.
What is the amount of salary (salary and additional
payments), staff, in one hour?
Do you need to hire a saw sharpener to keep it idle for a long time, or do you have an employee who is not very busy who can be appointed as a sharpener?
The cost of physical strength should come from an analysis of how many tapes an employee will need to re-sharpen in one hour.
It is also necessary to clarify the costs of a sharpening device, grinders and quality determination discs.
Based on this, the owner of the sawmill must find out how much the cost of re-sharpening the canvas is less than buying a new canvas.
In addition, a re-sharpened canvas may not work more than a new canvas.
Real benefits.
Eventually, the canvas will show signs of fatigue and the canvas will break.
Rapid tearing of the web can be eliminated if you use as large pulleys as possible, as well as keep it in good condition.
It is quite difficult to predict how long a re-sharpened canvas will last longer than a new canvas, and quite often the frequency of failure affects the way the canvases are used (sharpening or without re-sharpening).
The re-sharpened canvas fails after re-sharpening, and there are many reasons for this: fatigue of the canvas due to overloaded work of the canvas in poor condition, and even due to improper selection of canvases that were exposed to enormous temperatures, during re-sharpening this sharpener changed shape or overheated the recess between the teeth of the saw.
Like a large number of business decisions, an analysis of the assessment of all costs will help the owner make the right decision on this issue.
You need to find out the answer to the question: will there be a benefit from the additional working life of the canvas, can there be a downtime due to the replacement of the canvas?
09 Martha 2017
