With a history stretching back over 400 years, it is fair to say that change has come gradually at Bridport Foundry.
The company continues to create a wide range of cast products in iron, SG iron, bronze and aluminium for customers ranging from general engineers and architectural restorers to ‘steam’ enthusiasts.
More recently, it has progressed through a mix of organic growth and acquisition.
Since 1988, Bridport Foundry has been owned by the Lambert family; in more recent times the company has been run by brothers John and Steve Lambert, who — with a desire to develop and diversify the business — added complementary companies to the group.
With an interest in steam, the brother’s first acquisition (in 2004) was Plastow Traction Engines, a manufacturer of scale traction-engine kits and parts, of which many are cast.
With Plastow on board, it made “perfect sense to purchase its sister company Stuart Models”, which came up for sale in 2012 and is the world’s oldest manufacturer of model steam engines (the company was founded in the late 1800s by Stuart Turner).
As with the Plastow models, these are sold to customers as sets of castings for the customer to machine; they can also be supplied as pre-machined kits ready for assembly — or as ready-to-run models.
The working option
It was an increase in demand for the pre-machined kits and ready-to-run models that turned the brothers’ attention to investing in modern machine tools.
John Lambert says: “Having taken over Guernsey-based Stuart Models, we moved all of the existing stock to Bridport. To give some idea of scale, it arrived in 10 trailers, each 40ft long, almost bringing the town to a standstill.
"This volume of stock was indicative of the amount of machining that we were going to encounter; and while we initially sub-contracted all this out, it was a significant cost to the business — plus we lost some control over the quality of the finished products.
"The customer base for Stuart Models is made up of current engineers or ex-engineers aged between 55 and 90, who are quick to respond if the quality is not right.”
Given that space was available, the brothers decided to invest in machining capacity. However, as John Lambert openly admits, their machining experience was more ‘agricultural’ than precision, so any machine had to be user-friendly and easy to program and operate.
This led them to their first XYZ machine tool — an SMX 2500 ProtoTrak bed mill
(www.xyzmachinetools.co.uk).
“The machine’s control was a perfect transition for us moving from manual machines to CNC, being perfectly straightforward and easy to operate — even for someone with the limited programming knowledge we had. We are using the XYZ SMX 2500 mainly for pocketing operations, PCD drilling and tapping work on cast-iron components — work that is increasing as more and more customers are ordering the pre-machined kits.”
Easy operation
The confidence gained by having the XYZ SMX 2500 ProtoTrak bed mill made the next investment in a lathe much easier.
John Lambert said: “With the positive experience of the ProtoTrak control, it made perfect sense when we came round to buying a lathe to continue with XYZ, which is why we bought an SLX 1630 ProTurn lathe.
“This is being used to machine the many types of flywheel we need for the models; and with stock turnover being what it is, the machine is kept busy. We quickly gained confidence with the control; and if we ever have a question, we know that XYZ are at the end of the phone to help.”
The XYZ SMX 2500 ProtoTrak bed mill and SLX 1630 ProTurn lathe are the smallest machines in the XYZ bed mill and ProTurn ranges, with the bed mill having a 3hp variable speed (40-3,600rev/min) two-range R8 spindle (30 ISO optional) and a 1,245 x 228mm table.
Control is provided by the latest ProtoTrak SMX control unit, which provides positioning in two or three axes with canned cycles for: pockets of every conceivable shape (including pockets with islands); thread-milling; bolt-hole patterns; drilling; tapping and boring.
It can also perform 3-D surfacing with the on-board DNC capability. The SLX 1630 features a 400mm swing over the bed, a 54mm spindle bore and a between-centres distance of 760mm. Power is provided by a 5.75kW spindle with a speed range of 150-2,500rev/min (along with a constant-surface-speed capability).
For the ProTurn range, control is provided by the latest ProtoTrak SLX CNC unit, which allows the machine to be operated manually or under full CNC, with clearance cycles, profiling, grooving, drilling routines, and the machining of both standard and custom threads.