I am working on a project which will be implemented in rural Zambia and involves cutting 100mm dia. holes in corrugated sheets. There is no electrical power available so all cutting will have to be done by hand. I have attached a photo of the device which will be used. A hole is made in the sheet with a six inch nail and hammer then the profiled wooden support is held against the sheeting by passing the threaded stud through the sheet and the hole saw then the tension spring is added and the two wing nuts adjusted to give sufficient tension for the saw to cut.
But I have come across a problem. Because the saw blade has 5 tpi and the sheet approx. 0.5 mm thickness the blade quickly jams. However if I drive the saw in reverse it still continues to cut it's way through the sheet, slowly. Each hole takes about 12mins but this would be acceptable if I was confident that driving the saw in reverse will not severely shorten the life of the saw. My thoughts are that since the blade tips are heat treated to give optimum performance the trailing edge of the teeth must be as tough as the cutting edge. I would appreciate any comments
But I have come across a problem. Because the saw blade has 5 tpi and the sheet approx. 0.5 mm thickness the blade quickly jams. However if I drive the saw in reverse it still continues to cut it's way through the sheet, slowly. Each hole takes about 12mins but this would be acceptable if I was confident that driving the saw in reverse will not severely shorten the life of the saw. My thoughts are that since the blade tips are heat treated to give optimum performance the trailing edge of the teeth must be as tough as the cutting edge. I would appreciate any comments
