Holland & Holland sets its sights on machine safety with VERICUT

Globally renowned for its bespoke range of shotguns and rifles, Holland & Holland is a company that operates in an environment where art and engineering go hand-in-hand. Protecting the manufacturing technology used by the company is CGTech’s advanced simulation and NC code verification software, VERICUT.

Holland & Holland
Holland & Holland

Back in the mid 1800s Holland & Holland commissioned a purpose-built gun making facility in Harrow Road, North London. In the space of just 3 or 4 years demand increased rapidly and it became imperative that either the factory was enlarged, or a new factory was build. Henry Holland decided on the latter and a new, larger factory was built.

Completed in 1898, the company equipped its new premises with the most modern belt-driven manufacturing machinery available. Taking a ‘cottage industry’ and changing it to create an efficient industrial process with everything done under the one roof, a philosophy still proudly followed today.

In 1989, the company was purchased from the descendants of the original founding Holland family by the fashion house, Chanel. It was at this time the company invested in 5-axis machining technology and CAD/CAM software to support the drive to produce a new over-and-under shotgun designed for the American market for clay pigeon shooting.

This was when Engineering Manager, John Sperinck, joined from the aerospace industry. “The directors identified an opportunity for over-and-under guns in America. However, the design requires a great deal of work on very deep sections and using EDM and 5-axis machining methods gets you close to size much quicker,” he explains.

Using VERICUT simulation and verification software Holland & Holland ensures its machine tools can operate safely and efficiently
Using VERICUT simulation and verification software Holland & Holland ensures its machine tools can operate safely and efficiently

For the gun-maker engineering and art meet under its roof. The engineering department has a workshop equipped with machine tools and software, while the art element is held in manufacturing where the traditional setting or cutting to finished size and shape with hand-tools occurs. The legacy of the gun designs and the traditional skills passed down result in a product that is as much work-of-art as it is engineering excellence.

Most of the products produced now have engineering drawing, however for a company with such a long history there are some obscure customer requests that are not produced very often – so they do not warrant the time required to put them on the system. “That said, the London gun trade is suffering from a lack of apprentices and the skill base is diminishing,” John Sperinck says. “So, we need to capture the skills we have here before they are lost, and engineering software allows us to cost-effectively create designs even for small orders. We are more reliant on CAD/CAM to ensure we can continue to produce our products to the high standards expected by our customers.”

To support the programming of its 5-axis Kitamura Mycenter the company purchased CAD software. After running for about 10 years the machine had come to the end of its serviceable life, working day and night as components are machined ‘lights out’ overnight to get more productivity from a single shift.

“That was around 6 years ago, and we looked for an equivalent type machine in terms of machine structure and also size, because our workshop is in the basement and ceiling height is an issue. The Yasda machining centre we have now was selected because the configuration is very similar, and although a newer version it also featured a Fanuc NC system,” recalls Senior Engineer, Rob Bishopp.

Using VERICUT simulation and verification software Holland & Holland ensures its machine tools can operate safely and efficiently
Using VERICUT simulation and verification software Holland & Holland ensures its machine tools can operate safely and efficiently

The initial decision to invest in VERICUT verification software came about as a method of checking the NC programs, to verify they would run on the new machining centre. As some of the jobs had run for 10 years or more, no CAD data was available. To create these CAD models would mean a substantial amount of work. NC code verification using VERICUT provided a cost-effective approach to making sure the programs would operate. Rob Bishopp says: “Machines had got faster in the period of time that we had the Kitamura, and this is coupled with the fact that we run over night when there is no one there to press the emergency stop button.”

During overnight operation the rapid travels are reduced, running at 50 per cent rather than 100 per cent to extend the life of the machine tools. Typical cycle times range from a few hours to 20 hours or more, for example an action body requires 12 hours as its machined out of a solid 100 by 240 mm billet and has a lot of detailed work involved, including angle faces, drilled holes and tapped holes. Using the full 5-axis capability of the machine to hit five faces in one set up, after machining the part is wire cut off the remnant stock before the final face is spark eroded. All the complex copper electrodes for the diesinker are produced in-house.

“So, after 12 hours on the machining centre, wire cut for a couple of hours and sinking for another 10 hours quite a lot of material has been removed and the parts are very delicate. Every part is fully polished, so no machining marks remain,” Rob Bishopp explains. “In engineering, we are creating the foundations of the gun, so it has to be right,” John Sperinck adds.

Rob Bishopp loads a raw material billet into the company's 5-axis machining centre, and the fully machined gun belt swivel
Rob Bishopp loads a raw material billet into the company’s 5-axis machining centre, and the fully machined gun belt swivel

Once components leave the engineering workshop all the remaining operations are hand worked with the fine finishing/setting done in manufacturing using traditional methods. “Each customer’s gun is bespoke in every individual detail so they choose the wood, the engraving – everything about the weapon,” says Rob Bishopp. “It is an item of beauty that requires 4 months of working solidly around-the-clock. Many guns are on a three year order, so the customer is buying time from a skilled person life; the time that is required to complete their gun.”

John Sperinck says: “We provide a service to the skilled staff in manufacturing and I guess CAD/CAM provides the clear definition between the two skilled areas. We can take them a lot closer, a lot quicker to the finished hand-set product.”

Following the installation of the new machining centre jobs were verified with the simulation software as they required production. Rob Bishopp recalls: “CGTech created the model of the new machine and applied the dynamic parameters. As each job came up I took the old program, run it through VERICUT and made a list of what needed to change to get it to a state where the NC code would run and then checked for any errors, which VERICUT flags up in minutes. Some programs worked, some needed minor changes while some of the older programs had to be updated.”

Physical restrictions make machine tool selection and protection vital
Physical restrictions make machine tool selection and protection vital

These updates are carried out by John Sperinck using the Mastercam system with the new post processed tool path code sent straight to VERICUT to ensure it will run safely. For Holland & Holland, protecting the machine tool is of paramount importance as any collisions or crashes are difficult to repair and the lost production time is impossible to recover. “Once the NC code has been ‘VERICUT-ed’ and is ready to use it is transferred to the company server where it can be accessed by the machine, so the guys on the machine only see the safe code,” Rob Bishopp states.

Equipped with a 20-station pallet changer, the Brother machining centre used by the engineering department is also run with tool paths verified using VERICUT. The pallets provide flexibility as various components can be run, and the machine will run a batch of one, so up to 20 different parts can be loaded. However, Rob Bishopp tends to run two or three of each part.

Today, most of the old Kitamura NC programs have flushed through the system, other than the odd job that has not been made for a very long time. New designs that John Sperinck is working on will follow the proven process, using SolidWorks for CAD, Mastercam for the CAM element and VERICUT to provide 100 per cent machine safety. “For new programs there is no human intervention, no tweaking the program as that is where the errors are introduced,” Rob Bishopp concludes.

Article published in Machinery Magazine, November 2012 [PDF]
Article published in TCT, July 2013 [PDF]