Specac Ltd, a global provider of lab analysis spectrometers used in science and industry, has named Broanmain Plastics its new supplier of 2019.
Working collaboratively with the company for the past 12 months, Broanmain has assisted with the tool design, project managing the development of a new ATR (Attenuated Total Reflection) accessory for Specac’s high-spec spectrometry instrument. Comprising seven individual components, the Surrey-based technical moulder has now entered the manufacturing phase and is producing and individually finishing 100+ spectrometry ATR units a month.
Based upon Specac’s flagship Quest ATR accessory, the unit is used by forensic, life science, pharmaceutical, food, polymer, academia and healthcare labs the world over to analyse samples, measure quality and maintain full traceability.
Flying the flag for British engineering, one part within the unit involves repeatedly milling perfectly straight lines into a cylindrical component. It’s a complex operation ensuring the 3-dimensional contours follow an exacting pattern in the curve, time and again.
Given that it is an infrared optical component, with mirrors and crystal materials slotting into exact places within the ATR unit, everything has to be perfectly aligned. Achieving accuracy of the geometries and intricate cut outs cannot be accomplished by injection moulding alone. This is where Broanmain’s expertise in repeatable technical precision moulding came into play.
To increase the tensile strength to the moulded component, Broanmain uses a special resin with glass fibres inserted. All seven components are then moulded on various hybrid Sumitomo (SHI) Demag precision machines.
Rather than outsource the CNC milling process, Broanmain took the leap and invested in a vertical CNC milling machine. Automating the milling process furthers Broanmain’s already considerable expertise in designing and manufacturing high quality technical parts used in the medical, automotive, aerospace and electronics space. Equipped with a 10K RPM spindle and full Renishaw probing system, the mill accomplishes complex and repeatable 3D and 2D geometries and delivers better surface finishes on the most intricate of parts. Accuracy is further enhanced with the assistance of Renishaw’s TS27R tool setter and OMP400 part probe.
Making the moulding tool from steel hadn’t initially crossed Specac’s mind. Convinced it would be beyond its budget, Broanmain presented the Specac team with a range of options and a good business case to get the tool designed and built in China and shipped to the UK. The company also generated some fast prototypes through a partner in Germany, to ensure the design was fit for purpose.
Specac’s Strategic Buyer Anthony Gomme said: “Broanmain’s responsiveness, the ease of working with a single supplier, their tooling knowledge and general ‘get-the-job-done’ attitude has made such a difference to the speed we were able to bring this spectrometry advancement to market. The company’s willingness to invest in new technology, like the CNC mill, to support future engineering projects is testament to this.”
In order to meet Specac’s blue chip clients’ requirements, Broanmain also had to source an exacting protective paint finish for the ATR’s outer cover. Oldbury-based Applied Coating Technologies (ACT) successfully sourced the paint and developed the fine spatter finish in accordance with Specac’s expectations.
ACT’s Commercial Director, Christine Hancock explains: “Specac requires a fine spatter finish. This is achieved by developing an application technique that applies the spatter in a second coat. By varying the air pressure and volume of paint through the gun, you can vary the size of spatter achieved. At the time that Broanmain/Specac approached us, production mouldings for development were not available. Therefore ACT used trial plaques to develop a process that achieved a fine spatter to match a control plaque provided by Specac and later transferred this technique to the mouldings. Stringent quality control procedures are in place to ensure the same finish is achieved with each ongoing batch.”