Dartmoor Waterwheel Restoration
South Brent is a small town situated on the southern side of Dartmoor in Devon, about 20 miles from Plymouth. Although an idyllic rural community now, it was once one of the regionís powerhouses; the power before steam being generated by the rivers coming down from the moors. Joddy Chapman owns one such waterwheel on the bank of the River Avon that runs through his property. This huge waterwheel with a diameter of 20' and a width of 12' dates back to mid 19th century, though the site has had waterwheels dating back to 16th century. It originally powered a factory (long dismantled for its stone) that provided canvas for the naval dockyard at Devonport some 20 miles away.
The wheel remained and its power was then used to drive the machinery in a quarry that had started a few hundred yards away. The wheel fell into disrepair until some work was undertaken in the 1960s, mainly to the leat which takes the water from the river a hundred yards upstream. Joddy had been instrumental in restoring a neighbour's waterwheel around 10 years ago and using it to power a small generator. That wheel, with a diameter of approx. 9' and a width of 2', had been built of all steel and although still working successfully, is now suffering from corrosion. With the new much larger wheel the plan was to restore and strengthen the original steel frame but instead of wood or steel, using glassfibre for the paddles and buckets. The advantage of using GRP was that we could produce stiff and solid panels that would never rust or corrode and yet be lighter than steel.
The initial work involved the design and testing of sample panels to form the buckets. Each bucket consisted of two types of curved panels that, when four of them were bolted in place with GRP joiner sections, formed the backs and fronts. Both panel types were ribbed to help increase stiffness and stop any flexing. We used an isothalic gelcoat and a GP polyester resin all pigmented black. The panels were then laminated in a sandwich construction using three layers of 450 g/m² c.s.m. and 3mm upica as the core material. A total of 170 panels were moulded to complete the wheel.
The waterwheel is now running successfully and has been mated to an electrical generator producing around 8 kilowatts which will provide revenue for the foreseeable future. Just as solar power has become increasingly popular as a sustainable energy source, could there be a further source of green energy by the revival of waterwheels?
Spetisbury Round Tower Roof
We were commissioned to build a circular roof in glassfibre to imitate a traditional lead roof. It has a 6m diameter with a built-in gutter to the outer edge and accommodates a central sun pipe. Because of its size it was too wide to transport as one piece so the roof was divided into six equal triangular segments, each having one long side with an underlap to the next panel and the other side having a false lead roll expansion joint to overlap the preceding panel and form a weatherproof joint.
A pattern and mould were produced in house forming a segment of the full size. The segments were hand laminated with a grey gel in RAL 7015. Three layers of C.S.M. with a 3mm upica core forming a sandwich composite construction, lightweight but very stiff, the laminate being approx. 7mm thick. Six segments were moulded and transported to site where they were fitted together on the ground next to the tower and the whole was craned into place once the segments had been laminated together.
Plymouth University Marine Research Centre
Balfour Beatty were awarded the contract for building a marine research centre for Plymouth University at their Queen Anne's Marina site. This was a conversion of their previous Diving Centre and involved the construction of new buildings as well as refurbishing existing ones. The project also included the design and manufacture of the fixed laboratory equipment required for scientific research.
The study and research of marine plants and animals required a non-corrosive tray and racking system able to cope with a continuous flow of salt water, and also to be structurally capable of carrying heavy loads in the form of observation holding tanks. Glass reinforced plastic (GRP) being adaptable, inert, hardwearing and non-corrosive was the material of choice for the trays and we were commissioned to undertake this part of the project.
After our drawings were approved by the Clients we designed and manufactured the trays, all in varying lengths, widths and depths. For the racking we joined forces with Andrew Hicks Engineering of Winkleigh, Devon, with whom we have worked closely on previous projects, and they designed and built the frameworks, all in 316 marine grade stainless steel.
Due to limited access, part of the brief required trays and racks to be assembled on site in the wet laboratories rather than being delivered as finished units. A combined team from both firms working together completed this in 3 days.
Plymouth Gin Distillery & Museum - Replica Gin Vat in GRP
We were commissioned by Le Page Architects who were restructuring an area of the Plymouth Gin's Black Friars Distillery and Museum which is situated on Plymouth's historic waterfront area known as the Barbican. The distillery is one of the oldest buildings in Plymouth dating back to the 1400s and is protected as a national monument. It's rich history includes sheltering the Pilgrim Fathers before they joined the "Mayflower" and departed for North America.
Our brief was to build a replica gin vat that would act as a doorway and stairwell entrance to a new spiral staircase leading from the entrance foyer to a newly created leisure area downstairs.
The vat needed overall dimensions of approx. 3 metres high with a diameter of 2.2 metres. The construction to be in fire retardant glassfibre with a double skinned wall having smooth surfaces inside and out and finished in sandstone and black. The overall weight was kept to a minimum at approx. 270 kg. The shape mirrored the existing vats on display even down to the imitation weld seams around the base of the dome and the lower bowl of the vat. The door needed to be lockable and wiring provided for lighting. The external measurements were critical to fit the staircase which allowed only 50 mm clearance when manoeuvring through the listed building's entrance. Offloading into the entrance by hand was challenging but managed safely.
Exeter Library - GRP Roof Light Liners
Mansell's Construction Ltd. are, after a 12 month programme, completing the refurbishment of Exeter’s County library on behalf of Exeter City Council. The main hall of the lending library had natural window lighting in the roof. These were round conical tubes approx. 1.2 metres formed in concrete through a flat roof. Each roof light had a convex clear glass dome set into the top of the roof to bathe the area in natural light.
Whilst the originals were similar in shape, their dimensions varied greatly due to their being cast in concrete. Our task was to produce a maintenance-free GRP liner of one size that could be fitted easily into all existing originals whilst still allowing the glass to perform its original task as a roof light and also to bridge the gap to a new suspended ceiling now being formed some 300 mm below the original. With measurements taken we prepared a pattern and mould and manufactured 14 mouldings all within a 5 week time span.
The mouldings have a smooth internal gel finish in traffic white with the laminate being 2 layers of 450 g/m2 c.s.m. They were sealed in place with a p.u. bonding adhesive and the base flange supported and sealed by the suspended ceiling so that no fastenings were visible. The linings have been given new life to an original feature without the need for continual painting and maintenance as happened before.
This innovative, rust-proof, fibre-glass Water Transporter allows anyone unable to lift even a small watering-can to transport water with very little effort from an outside tap or to siphon it from a waterbutt. Sturdy wheels give great manoeuvrability on a smooth surface, and a foot-brake gives control on slopes.
To prevent spillage on slopes and give a comfortable fixed handle at waist level, the Transporter is much taller than the practical level of water carried (which varies with acceptable weight). Height can be varied to allow the user to reach to the bottom with a jug.
Man Friday makes the fibre-glass container (the colour of which can be varied) to fit into a stainless steel custom-built dolly supplied by Fletcher European.