One of the most advanced Erowa robot loaded machining cells in the UK can be found at TMB Patterns in Bridgwater, Somerset. Here, the company provides design and manufacturing support for customers demanding high quality thermoforming tools and ancillary equipment predominantly for the packaging industries.
TMB was originally established in 1977 by current Managing Director, Martin Baker, and his then business partner Terry Morley in a ‘shed’ located on a scrapyard, to provide patterns and sample packaging trays for various customers. Today, the company is one of the UK’s largest thermoforming toolmakers employing around 100 highly skilled staff to produce up to 20 form/cut/stack tools per week and turning over around £5 million per annum.
“We were literally two guys working hard in a scrap shed,” recalls Martin Baker. “A visit from one of our main customers highlighted the fact that we needed to raise our game. So we bought a piece of ground, built a small factory and grew the business from there. We worked 7 days a week and invested in the latest technology. In the 1980s we installed a Bridgeport Interact NC milling machine and could clearly see that that was the way forward. Eventually we knew we would replace the casting of tools with CNC machining from solid.”
Then, 10 years ago, Martin Baker’s former partner decided it was time for him to hang his overall up and play golf, but not before the company had moved to its current 20,000 ft2 facility that features LED lighting and air conditioning. It was here that the direction of the technical investment turned to robotic automation to ease the cyclical nature of the company’s workload. As Martin Baker explains: “At the end of September every year the work drops off and when you employ a lot of skilled people you have to save through the Summer to pay for the Winter. I realised that automation could help with this fluctuation so I went over to Switzerland see the Erowa system in operation. I was very impressed with the company and its products, with over 2,000 robot systems installed I felt Erowa certainly had the experience to support my company’s goals.
“I extended the factory and invested in an Erowa linear Robot Dynamic system feeding four 5-axis machining centres. Even though we had all the necessary people with all the required skills it really was rather different. You have to get your head switched on to automation and it has taken 12 months for everyone to get on board.”
Pairing machine tools is one of the key elements according to Martin Baker, so the robot cell remains flexible but has the functional backup should any machine tool need to be taken out of service. Software is another crucial element he says: “We work with Delcam to provide our CAM data for the Heidenhain CNC systems fitted to the DMG and larger capacity Hermle machining centres within the Erowa cell. Although we plan which machine will be producing a part the Delcam software produced the post processed NC code for both machine types in case we need to switch over for any reason.”
At TMB the back face of the tool is machined first with the raw billet of aluminium bolted onto the Erowa pallet that contains an RF chip with identity coding as well as additional intelligence for live tracking and data transfer. Once the back face is complete the billet is bolted to the pallet to present what will become the working surface of the thermoforming tool to the machine tool’s spindle. Pallets weighing up to 250 kg can be manipulated by the robot.
“We might be producing 6 or 26 tools, whatever the quantity we tend to do everything inside the machine once the robot has loaded it. All the roughing and final finishing along with any engraving that is needed is carried out. The only final operation required is the sparking of all the vent holes in the tool cavity. The small diameter and quantity of holes required means EDM drilling is the most efficient method,” Martin Baker states.
As a secondary check to the Erowa pallet data the raw material is probed to confirm the expected size billet has been fitted. Any deviation will result in a text message being sent to the relevant staff that can quickly rectify any issues.
Another strength of the Erowa system is its scalable nature, such that additional or even different machine tools can be added as demand increases along with extra pallet racking to increase the capacity of the cell. TMB is already considering the option of an additional machining centre to improve its productivity even further.
Although the Erowa Dynamic Robot cell and machining centres represent a significant investment TMB Patterns estimate a payback for the automation of around five years. “I was always interested in the development of robotic automation systems, but didn’t think it would be a possibility for a company such as mine to install one within my working life time,” Martin Baker concludes.