The contract inspection and reverse-engineering capacity at Laser Scanning Ltd — based in Chapeltown, near Sheffield — has doubled, while the size of component that can be measured has increased more than five-fold.

This follows the installation of a second — and larger — co-ordinate measuring machine (CMM) built by LK Metrology at its Castle Donington factory (www.LKmetrology.com). The latest machine — an LK 20.12.10 ceramic-bridge CMM with a 2,000 x 1,200 x 1,000mm working volume — has joined a smaller 8.7.6 model.

When Laser Scanning’s managing director Johnathan Rigby started the company in September 2016, he brought with him a machine from his previous employer — PMS Diecasting (based in Rotherham), which now sub-contracts much of its metrology requirement to Laser Scanning.

Both firms are members of the Glide Group, along with plastic injection-moulding specialist Loadhog, tool-maker GoTools and wire-joining and tensioning-product manufacturer Gripple.

As the inspection provider’s name implies, most data acquisition is by laser scanning on both of the LK CMMs, as well as on two ‘articulated arms’ supplied by Nikon Metrology.

All of the equipment is housed in a temperature-controlled room held at 20°C ±1°C. Furthermore, parts delivered for inspection are ‘acclimatised’ in the same room for 24hr, to reduce measurement uncertainty.

Three types of non-contact sensor from Nikon Metrology are in use on the CMMs: an XC65D cross-scanner, and line-scanner models L100 and LC15Dx.

These have measuring accuracies of 13.0, 6.5 and 1.8µm respectively; the latter provides a performance equivalent to tactile probing, which is also used by Mr Rigby and his team for capturing physical dimensions (such as hole diameters) with a TP20 touch probe and an SP20 scanning probe — both from Renishaw.

A changing rack mounted on the CMM table allows automatic sensor exchange within an inspection cycle.

Prompting purchase

The purchase of the larger CMM was prompted by Mr Rigby’s receipt of a contract from JCB Power Systems in Derby to assist with the quality control (QC) of cylinder blocks and cylinder heads for the engines that power the OEM’s off-road vehicles.

JCB has its own LK machine equipped with a touch probe that serves the production line in Derby; Laser Scanning assists by providing measurement and inspection of ‘goods in’ at the plant, where it has a QC engineer permanently stationed.

Additionally, Laser Scanning helps out with preparing CMM programs and proving them out, as well as inspecting prototypes to support JCB’s research and development department.

The Chapeltown facility can provide much more comprehensive and accurate information about a new component than is possible using the touch-probing techniques at JCB Power Systems; and while the engine plant does have a laser scanning capability on an articulated arm, the level of detail that can be acquired is less, as at 23µm its scanning resolution is much lower than the best CMM-mounted scanner in use at Laser Scanning.

In any case, inspection using an arm would be a ‘manual process’ and almost impossible to replicate on subsequent occasions; running a program on a CMM is ‘automated and highly repeatable’.

Mr Rigby said: “By working with JCB’s Inspection department and R&D team, we have been able to free up our customer’s machine to concentrate on production QC.

They also appreciate the greater detail we can provide about new prototypes, as laser scanning allows us to show the form of a component, as well as supply measurement data.”

Application example

Highlighting an example of the level of detail available, Mr Rigby said: “JCB recently asked us to help them with a new rocker-cover housing that had been plastic-injection-moulded, to determine whether the gasket area was within tolerance after shrinkage in the manufacturing process.

Inspecting a planar surface such as the gasket area by touch probing at multiple points would not give an overall idea of its flatness; and in all probability, if the exercise were repeated, the results would be different.

“In contrast, scanning generates millions of points to give a detailed 3-D picture of the entire surface to a very high level of precision — and the deviations can be quantified.

“This level of detail enables JCB to show its mould tool supplier exactly where any inaccuracies are.”

Laser Scanning says it is ideally placed to help any manufacturer that uses LK measuring machines and software, as work and programs can be transferred seamlessly to run on either CMM.

Projects have involved a Tier Two supplier in the Midlands to the global aerospace industry, which used Laser Scanning’s sub-contract services for inspecting components while its own machine was out of action; and a medical-equipment manufacturer that wanted to verify its in-house QC capability. Operator holiday cover is another regular source of business.

About half of Laser Scanning’s turnover is derived from reverse-engineering ‘legacy’ components for which models and drawings do not exist.

Machine shops and tool-makers are frequent customers; the company also provides a service to designers.

A recent job entailed taking ‘sketches’ for the frame of a new ‘downhill’ mountain bike developed by Stewart Palmer (a director at F1 sub-contractor North Bucks Machining) and creating a 3-D CAD model, so that the frame elements could be produced on one of his firm’s machining centres. This machinist is also an LK CMM user.

Supporting software

The latest version of LK Camio software — version 8.5 — is in use at the Chapeltown facility. Featuring interoperability across CMM platforms and sensor technologies, it is designed to create efficient inspection programs for measuring geometrical features and evaluating surfaces using advanced point-cloud analysis, with part-to-CAD comparison and full reporting capability.

Mr Rigby concluded: “Camio software has a Microsoft Office feel to it, with a similar customisable icon ribbon at the top of the screen.

It is very user-friendly, as programming functions are easily accessible and not buried within drop-down menus. The new version interfaces with our Geomagic software from 3D Systems, allowing us to create accurate models from 3-D scan data, as well as use it for QC and measurement.

“We regard our association with both LK and Nikon as two-way partnerships, whereby they give us all the support we need and we feed back information to the OEMs to assist in their development of the next generations of products.”

Laser Scanning is accredited to ISO 9001 for quality management, ISO 14001 for environmental management, ISO 18001 for occupational safety and health, and ISO 27001 for data security.

It is a member of the GTMA (Gauge and Tool Makers Association), the Federation of Small Businesses and the Employee Ownership Association.