Pushing new gear wheels of precision

It’s a basic fact of mechanical engineering that if you want something to move then there will almost always be some sort of gear assembly involved.

It’s no surprise then that down the years, Muffett Gears has acquired not only a broad range of metalworking equipment, but also a long legacy of skills and knowledge to manufacture these essential components. For more than 90 years this third generation, family owned business, based in Tunbridge Wells, Kent, has been providing engineering solutions for every conceivable gearing application.

Currently employing around 50 staff, with a turnover of £5.5 million, the company supplies gears, gearboxes and precision components and sub-assemblies for a wide range of sectors including medical, aerospace, defence, oil and gas, marine, construction and media, in products as diverse as body scanners, TV cameras, hydraulic pumps, winches and mobile satellite dishes.

The company can hob, shape, broach and grind gears from 4mm to 400mm pitch circle diameter (PCD) with a module (the ratio of the diameter of the gear divided by the number of teeth) from 0.25 to 5.0 in any machinable material. It can also turn, mill, grind or EDM parts to offer assembled gearing solutions.

So what has been the reason behind the company’s longevity? Mark Jagelman, operations manager, at Muffett Gears says: “It comes down to really understanding what our customers want from a gearbox and how they want that product to work. The application can mean that the gears are manufactured in very different ways. We have to adapt our manufacturing processes or the build procedures for a particular customer’s requirements to reach a cost-effective outcome.

“Whilst we do not hold design approval under our AS 9100 Rev C registration, we help our customers at the front end of their projects with our ideas and experience of how gears work and how they can be manufactured. For example, is it best to make the part from solid or is it better to forge it or cast it, can a gear casing be made in one piece or two?”

Broad horizons

One of the company’s biggest contracts is supplying sub-assemblies for oncology machines used for scanning cancers and treating patients with radiotherapy. Incorporated in the machines are Muffett gearboxes, electro mechanical assemblies and subassemblies, standard parts and kits of parts, some of which are exported to China and then returned back to the UK to be built into the final machines.

Other long-term contracts involve intricate gear assemblies for a major aerospace OEM, yellow goods suppliers and gearboxes for a globally exported industrial heating system.

Muffett has a policy of continuous investment not only in new equipment but also in its staff. The company has just installed a new Doosan DNM 5700 machining centre from Mills CNC, joining a similar machine it purchased last year.

“We constantly assess what equipment we need and we are not afraid to invest in new technology if the volumes involved mean we can carry out a contract more cost-effectively,” Mr Jagelman says.

Other machining technology found on the Muffett shopfloor include Traub and Mori Seiki turn-mill centres, a Studer grinder, Koepfer and Gleason gear cutting machines and Sodick EDM.

“We have a wide range of equipment because we need the flexibility. We manufacture very small gears of 0.25 module and larger gears up to 400mm in diameter, in a wide range of materials from unusual alloys to filled plastics. There’s not really one machine that can do that wide range of work.”

The company has also invested heavily in its inspection capabilities, including a Zeiss CMM and gear checking software able to check 17 different features on a gear.

“This means we can validate everything that we manufacture,” Mr Jagelman explains. “More and more customers want first article inspection (FAI) or Production Part Approval (PPAP) so inspection reports have become an absolutely critical requirement for the parts that we supply. On some of our work our customers require 100% inspection on every feature of the gear, so it can be the case that inspection of a part can actually take longer than the manufacturing time.

“We are also on some occasions asked to do capability studies keeping to certain process capability index (Cpk) values and we have also carried out Statistical Process Control (SPC) so when it comes to inspection we are very much driven by whatever the customer’s requirements are.”

Another part of Muffett’s work is involved in R&D and pre-production projects before contracts are moved to large volume manufacturing.

“We are very strong at taking the conceptual ideas from our customers and prototyping, pre-production work, first runs and small to medium volumes. With a lot of our customers our work involves Kanban type contracts with small amounts of stock.”

Cost-conscious options

However, with these kinds of contracts Muffett Gears cannot afford any room for complacency. Customers are always looking for cost downs and shorter lead-times and this is why Mr Jagelman is keen to look at ways to increase workflow and adopt more automation. Muffett’s next big investment will be a fully automatic gear hobbing machine with a ring loader.

“Even with high quality parts and long-term contracts we are always under pressure to reduce cost,” he says. “Reducing cycle time used to be the main way of increasing efficiency – that’s why mill-turn lathes became more popular because you could reduce operations and set-ups. Now the simplest way to reduce hourly rates is through improved workflow. We need to achieve longer continuous running of some of our machines and automation is the best solution.”

However, given the nature of its work Mr Jagelman acknowledges that Muffett will always need a high degree of flexibility to bring in new contracts and build on its reputation for being able to carry out challenging projects: “We will always consider the best manufacturing options. You need to have that flexibility to remain competitive,” he states.

Like many engineering companies Muffett Gears is also aware of the need to keep staff and skills in place and up to date with new technologies. The company currently has five apprentices able to draw on the experience of some of its longest serving employees helping them to gain an all-round understanding of engineering.

“Our apprentices spend time manufacturing, working in inspection and assembly,” Mr Jagelman affirms. “This means they understand how to interpret a drawing or CAD file, measure, and make the part and then understand why the part is manufactured in the way it is so it can be part of an assembly. Gear making is a very specialised skill and this all-round experience is very valuable.”

The company has also recently introduced Edgecam CAM software which meant significant training was needed for its staff: “The staff are the core of the business,” Mr Jagelman adds. “We like to keep everyone involved and inform the team about our current projects. We consult the relevant staff about future investment in equipment and training because we all have a common goal of growing the business.”

Manufacturing model

So, at the moment things bode well for Muffett Gears. Orders are growing, exports are increasing and investment is continuing. In fact, the company could be seen as a positive template for many in UK manufacturing.

“We operate in a global market in many different sectors, where customer expectations can be very different. Mr Jagelman concludes. “You always have to be aware of new opportunities. We like to engage with our customers and explore their needs because we can offer them the complete solution which gives us added value.

“With one customer we started supplying gears only – now we supply the whole gearbox assembly which is used worldwide. So, an order that starts at just £500 can easily grow into to a £50,000 per month revenue stream.”

Muffett Gears www.muffettgears.co.uk