Without VERICUT the production picture would be incomplete

Establishing a high precision engineering company supplying mould bases to an international plastics injection moulding market requires skilled and experienced staff. But what do you do if they are not available? This was the problem faced by Tirad, so the company invested in the best equipment and software available to support its business plans. VERICUT CNC optimisation and verification software has proved to be one of its most significant investments.

There can be little argument that ice hockey is one of the toughest team sports, so when three players decide to establish a business together you can be sure they will battle hard to be successful. Based in Vysocina, around 75 miles to the South East of Prague, Tirad was initially established in 1993, as an international logistics company before purchasing a Unix workstation with Euclid CAD/CAM software in 1994, to produce NC programs for external engineering companies. As the logistics business declined the transport equipment was sold to purchase its current workshop and the company’s first CNC milling machine in 1996.

However, at that time no one could operate it and experience with CNC machine tools was very limited. Managing Partner, Stanislav Vesely, recalls: “We could program the milling machine but we had no experience of setting it up. Experience was not available locally, so we employed tradesmen with other skills and a strong desire to learn. So everything had to be prepared for operators that had very little experience.”

Tirad’s focus has remained on how to keep the methods simple for the operator; it is still the main philosophy of the company today. “We have precise machine tools and we focus on how to use them effectively without skilled people. Now the operators are more skilled, but we still keep it simple and let the machines do what they can. Many of the original tradesmen are still with the company and are an important part of the team. The most important thing for us is a ‘can do’ attitude. If there is desire all things are possible,” says Stanislav Vesely.

Until 2000, the company provided subcontract engineering services to various industries. Then the business decision was taken to focus on the precision parts for mould bases of plastic injection tools. The goal was to be the best supplier of the bespoke mould bases, which are extremely demanding on accuracy and to build long-term relationships with international customers.

VERICUT was installed in 2005, to improve productivity by identifying any problems with NC code before it was passed to the machines in the workshop. With technical support provided by local VERICUT agent, Axiom Tech, the company started a comprehensive project to model every element involved with the production of mould bases in 2010.

CAM programmer applied VERICUT NC simulation to the company’s 5-axis Huron machining centre.

Now all the milling and drilling machines have been modelled, built to reflect exactly how each machine is used. A Diamach 3-axis milling machine was modelled first followed by a more complex Huron 5-axis machine that was very important to key customers.

Customers supply 3D models which are taken into Pro/Engineer or Siemens NX CAD systems before the NC tool paths are applied using Edgecam CAM software. The Edgecam interface allows the NC program to open directly in VERICUT for verification and optimisation. The software is used by a skilled programmer so he checks all the set ups before they go to the shopfloor. Using VERICUT prior to releasing the NC code to the workshop has helped Tirad with its philosophy of keeping things simple for operators who are less skilled.

Parts for machining always follow the same procedure. The NC program is prepared and set up and run through VERICUT. Any mistakes are reported back to the programmer who carries out any modifications and corrections. The toolpath is then re-checked with VERICUT and when clear it is released to the company’s network.

Tirad operates a paperless environment with NC programs transferred to the shopfloor via its intranet. Every machine tool has a PC with software for viewing the CAD file and also the VERICUT Reviewer. A feature of the latest version of VERICUT, Reviewer is a collaboration tool that allows 3D simulations to be shared with anyone in the business without the need for a VERICUT license. The Reviewer can play forward and backward while removing and replacing material. Error messages and NC program text is highlighted when a collision on the stock or fixture is selected. A tool path line display is optional. The operator can rotate, pan and zoom just like normal VERICUT, and the cut stock can be measured using all the standard X-caliper tools.

Cutting conditions are shown in the status display and available when stepping through the program using NC Program Review. The feature shows detailed information about the cutter’s engagement with material, including: axial depth, radial width, volume removal rate, chip thickness, maximum surface speed and contact area.

The shift leader on the shopfloor can resolve mistakes using VERICUT and if the file is modified it is reported and uploaded back to the CAM programmer for updating and storage for future use, as parts can be re-ordered by customers.

A comprehensive shopfloor data collection (SFDC) system is installed at Tirad and every machine has PLC-based monitoring equipment which reports on the machine’s status, such as running, waiting, stopped, spindle over-ride and so on. It allows the company to collect data, analyse machine/tool/material performance, and improve from a known datum.

“Monitoring processes from accurate data collected from machines is vital to business decisions. Thanks to SFDC it was possible to compare productivity during the implementation of VERICUT and to analyse efficiency gains of using the software. Continual production on machine tools without errors in NC code to stop the machines has improved our efficiency significantly, and the return on investment was achieved within 18 months. Beyond that, VERICUT has increased our capacity so we can grow. Without it we would spend too much time repairing errors and not be able to move the company forward,” states Stanislav Vesely.

Today, over 20 high precision machine tools and 92 staff are committed to achieving a positional accuracy at 7 micron within a 1mmould base length, but the drive is to now achieve 5 micron and the whole company is focused on achieving this. Raw material for the mould base is very expensive and customers require high precision and ever larger mould bases on shorter lead times, typically 4 to 6 weeks, and the raw material delivery can take more than two weeks.

Every mould base NC program has to pass through VERICUT for productivity and to ensure the safety of the machine tools. Tirad’s aim is to achieve a working tolerance of just 5 micron across the whole company.

Stanislav Vesely explains the elements for high accuracy: “You need good machine tools with a planned maintenance schedule. Environmental control so that all machining is carried out in known conditions. High quality solid carbide cutting tools must be used and, finally, qualified staff.”

All of these elements can be purchased except the staff which must be trained. All of Tirad’s maintenance is done in-house to ensure accuracy. Everybody on the shopfloor has been trained to measure everything because experience counts when checking the finished size.

Stanislav Vesely concludes: “VERICUT is one tile in the whole mosaic, but without it the production picture would be incomplete.”