Sawing time calculation

[lyvince]

Hi all,
Can someone provide the formula for calculating the sawing time by using a horizontal band saw machine?

To saw the following materials:
Example 1:
-Solid 8" bar
-4140 steel

Example 2:
-Tube with 8"OD x 5" ID
-4140 steel

Thank you.
-V

 

[twinny]

4 sq inches per minute for steel
10 sq inches per min for ally