Ten sliding-head Citizen lathes in five years transform production efficiency

Established in 1995, toolmaking, metal pressings and plastic injection

moulding services provider TWP Manufacturing Group, Tipton, started making

a range of proprietary products after the financial crisis of 2008 to build

business resilience. They include photographic studio and darkroom

equipment, gardening items such as wheelbarrows, and spiral security

anchors. Most of the items that go into them, including stamped metal

platework, milled components and moulded plastic parts, are produced in-

house and assembled into the various products, together with a large variety

of turned parts that historically were mainly sourced from suppliers in the Far

East.

That changed in May 2020 with the purchase at auction of a Japanese-built,

CNC sliding-head turning centre, a Citizen Cincom M32 that was 19 years old

at the time. The twin-spindle, 32 mm capacity, bar-fed lathe, equipped with a

tool turret, a gang-type tool post and a back tool post for reverse-end

machining, brought in-house about half of the outsourced turned parts

production.

Fast-forward five years to the spring of 2025 and the number of such

machines on the shop floor had risen to 10, all pre-owned and mostly of similar

age. Not only had all the previously subcontracted turn-milling work long since

been repatriated, but a turned parts subcontracting business had also been

established that now accounts for 30% of the firm’s £4.2 million current annual

turnover.

Five years ago, income was £2.5 million per year, which means that business

has increased by more than two-thirds in that time. Notably, during the same

period the headcount has decreased by 20%, to 28 staff, so earnings per

person employed has jumped by more than double.

Phil Stanley, joint owner of TWP together with partner Richard Perry, said,

“Our relationship with Citizen Machinery UK has been brilliant since the start.

Despite our repeated purchase of used machines, nothing has been too much

trouble for them over the years.

“They were there for us when we installed the first M32, helping with advice

and early programs. If the assistance from their engineers had not been

forthcoming, we would not have been able to progress.

"The support we have received all the way through each of the 10 lathe

installations, including refurbishment and realignment of the machines, has

been second to none and they are still behind us every step of the way.”

Four months after the first Cincom arrived, a second Citizen sliding-head lathe

of the same bar capacity was acquired, an L32 equipped with exclusively gang

tooling and the facility to eject shaft-type components through the sub spindle.

It proved ideal for producing a main component in one hit for the gear shift

lever of a Lotus car. Virtually every other component that comprises the

assembly is also produced in-house.

To provide extra capacity, bring down lead-times and allow TWP to introduce

just-in-time manufacturing procedures, a second M32 was purchased in May

2021\. By this stage, all turn-milled parts production had been insourced. It also

allowed the manufacturer to get ahead with forward orders and gain new

business.

With the aim of transferring sub-12 mm diameter parts production from the 32

mm capacity sliding-head turning machines to more appropriately sized,

nimble lathes, two B12 Cincoms arrived in August 2022. Among numerous

other jobs, they are used around the clock every week for turning 10,000 mild

steel pins that go into control boxes for heating and ventilating systems.

The following year, in June and August respectively, Citizen delivered two 20

mm capacity Cincom L20s, enabling work to be allocated more efficiently

across the shop floor. It also avoided having to set up machines before a batch

run had finished to accommodate a contract that needed to be fulfilled

urgently. The extra lathes provided much-needed additional capacity to cope

with more work that was being received from existing and new customers.

Wishing to produce components from larger bar up to 64 mm diameter, Mr

Stanley opted for a triple-turret lathe from Citizen’s other product line, Miyano.

An early job put onto the machine compressed into a single operation the

manufacture of a high-strength 6082 aluminium T6 cable link for the Lotus

gear shift. Before the machine’s installation, the maximum bar diameter that

could be processed in the Tipton factory was 55 mm.

Most recently, following the clearance of a storage room to provide additional

manufacturing floor area and the relocation of various machines, two

additional Cincom models were added in February and April 2025, both M32s.

This part of TWP’s facility was officially opened on 14th March 2023 by West

Midlands Mayor Andy Street and Shaun Bailey, MP for West Bromwich West

at the time, who both also toured the entire factory comprising three industrial

units.

Despite the Citizen lathes all being second-hand, which allowed TWP to buy

them without the need for finance, the Citizen lathes work like new machines,

according to Mr Stanley. He said, “We hold a general tolerance here of ± 0.05

mm, but we have turned a carbon steel pin to +0 / -2 µm on the L32 – not bad

for a lathe built a quarter of a century ago!”

He puts this performance down to the extreme rigidity of Citizen lathes,

coupled with the use of good quality coolant and judicious choice of feeds and

speeds. This combination not only promotes high dimensional accuracy and

good surface finish, but also long tool life. He noted recently that on one lathe,

each edge of a carbide insert, when machining parts from mild steel bar, did

not need to be indexed or replaced before 1,800 parts were produced.

A total of 800,000 turn-milled components per year are machined on the 10

Citizen lathes, two-thirds of them from mild steel, while stainless steel

accounts for another 30% of throughput. As a large proportion of components

include spanner flats, extensive use is made of hexagonal bar to avoid milling

them and lengthening the cycle times. The robustness of the Citizen lathes,

and their ability to withstand the inevitable vibration when turning such bar, is a

major benefit in this respect as well.

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M4S TAKE

My take: AI claims need scrutiny. The useful implementations reduce cycle time or defect rates in measurable ways. Vague promises about 'optimization' without specific metrics are usually marketing.

Simon McLoughlin