Laser cutting sheet metal parts is very common in the industry. Not too many years ago laser cutting was new and estimating the costs was new. Now, laser cutting estimating has become much more accurate through software simulations.
The simplest way to estimate laser cutting time and material is using the actual laser programming software like Metacam by Metamation. A flat DXF file can be loaded into the software and the software will accurately estimate the laser time based on a simulation cutting the part. The part can actually be nested giving you a more accurate time cutting the parts from a nested sheet. Once the estimated time has been calculated you would enter that time into the cycle time of the nesting software to calculate your costs. The Gas, Depreciation, Utilities would be included in your overhead rate of the machine which in turn gives you the cost to run the part.
There are other situations where you do not have a good DXF file and you must estimate by estimating the number of inches, pierces, cut speed, etc. The screen shot below shows where you would create an a formula and use the formula to enter values. The formula would have to be customized for your specific machine and manufacturing process which in turn brings consistent estimates.
Lastly, a calculator can be created to assist you in calculating the number of linear inches of cutting as shown below.
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