by Bryan Jacobs
Be ready to produce production parts prior to machine delivery
Most companies utilizing CNC machinery, regardless of the industry, already use digital manufacturing technology to improve their NC machining processes. But some companies don’t realize that simulation and verification software can be utilized even before a new CNC machine has been delivered. This type of software is widely known for its ability to prove out a cutting process off the machine. Instead of using the machine to test out and optimize programs, shops can avoid machine downtime and costly collisions that might occur during on-machine prove-out.
When a company purchases a new CNC machine tool, the process is usually chronological: a specification of the requirements is created, a machine is selected, and after negotiation, a delivery date is set. Once the machine is delivered, the shop then begins the process of creating new part programs and running first part prove-outs. By the time the post-processor is fine-tuned and production parts are being produced, many valuable months may have passed.
Waiting for machine delivery
NC simulation software can significantly shorten the time it takes to get from the initial machine selection to production parts. Some manufacturers have figured out how to get new machines up-and-running quickly by completing several implementation steps concurrently. Shops can be creating and proving out new part programs before the machine has been delivered.
To be successful, there must be 100 per cent confidence the simulation exactly matches the behaviour of the machine ordered. End users are becoming more sophisticated and beginning to recognize that process analysis features within the simulation are important. It’s easy to lose sight of this fact in the visual world of machining simulation. Pretty pictures are nice, but process simulation is an engineering analysis tool. It doesn’t matter how nice the images look if the simulation is unable to alert the user of process problems such as small-but-disastrous workpiece gouges. Unfortunately, some software simulation methods reduce accuracy for faster simulation speed while hiding unrealistic flaws with graphic shading “tricks.” Not only are the flaws hidden, but so are process errors.
Using simulation to spec the machine
Some companies have taken simulation even further up the process cycle by using simulation software for CNC equipment concept design and evaluation prior to purchase. Simulation can even help a manufacturer determine if a particular CNC machine being considered will adequately meet the company’s machining needs. Companies can test the latest machine technology, without having the actual machine in place.
Accurate simulation of a physical machining process requires virtual 3D model equivalents of the stock, fixtures, tools, and CNC machine. However, creating these models in a CAD system, either by measuring the physical pieces or transferring the dimensions from 2D drawings, can be a tedious, time consuming process. The time and/or cost of this modeling process can be a disincentive to realizing benefits of simulation. It is obviously desirable to have “simulation-ready” 3D models available from the original equipment suppliers, eliminating the end user having to create models or hire someone to do it. Fortunately several machine, cutting tool, and fixture suppliers realize this need and have taken steps to meet it.
This is good news for all simulation software users: suppliers of factory equipment are now acknowledging and rushing to fill the needs for pre-process simulation, making 3D models of their products generally available to end users. Some of the more advanced manufacturing companies, who depend on machining simulation to meet their production needs, now require CAD models with the purchase of a new machine. The increased willingness of machine builders, cutting tool and fixture manufacturers to share 3D models is making it easier than ever to get up and running with accurate CNC simulation software. Improving the data exchange methods and tailoring the 3D models content to work more efficiently in simulation will greatly simplify the simulation implementation and its daily use for end users. When software and hardware suppliers work together for the benefit of their mutual customers, everyone wins. SMT
Bryan Jacobs is marketing communications manager at CGTech.
