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Other Brunel's Swing Bridge PagesAs well as an introductory page, the other Brunel's Swing Bridge pages cover: events at the bridge, including the dates of work parties; reports of work parties in 2019, 2020, 2021, and 2022; photos of work parties in 2020, 2021, and 2022; information on the 170th Anniversary events; and copies of the display boards. Brunel's Swing Bridge Project News - 2018October 2018The rusted nuts holding down the south east and south west bearings had to be heated before being freed off. A special lifting gantry was used to raised the south west wheel and its heavy cast iron bearing, so that the underside could be cleaned, carefully measured packings installed, and the wheel/bearing assembly reassembled.
September 2018The site was open on Saturday 15 September as part of the Heritage Open Days scheme. There were 100 visitors, including some potential new volunteers. Among the items on display were some photographic boards, artefacts and the enormous spanner that was used unsuccessfully to unscrew the large central bolt (photo right).
August 2018A group of University of Birmingham students were visiting the docks area with their professor on 31 August as part of their railway MSc course (photo right). They were given an unexpected bonus of a guided tour of the bridge, as there were two volunteers working on a survey. There was a lively discussion on the design of the turning gear, Brunel's 'abilities' as a mechanical engineer, and the extraordinary achievements of the metalworkers who actually constructed the Bridge. On 18 August the south east wheel and its bearings were installed, which required a fair amount of dressing of the new bronze bearing-castings to make them fit their cast iron plummer blocks. The levels of the wheel-crowns were checked and rechecked using a very accurate engineer's level (photo below right). Three wheels are slightly low and will have to be raised by inserting some packings.
The south wall of the shed was given an undercoat, ready for the top coat to be applied at a later date. The backing boards for both interpretation boards were replaced. On 04 August the last 250Kg wheel arrived, and was moved on rollers to the centre of the bridge before being lowered into place. The nuts holding down the bearing of the south west wheel were freed, the bearing aligned and settled down on its new bronzes. The caps were refitted and the level checked against the adjoining north east bearing. It was about 5mm low, so 5mm of copper packing will be fitted under the bronze shortly. The rusty cast iron pintle was sanded clean. July 2018The four new bronze shells were fitted to the south west wheel's plummer blocks (those are the big cast iron chairs the bearings sit in). There is a slight misalignment between the two blocks, and they will have to be realigned at a future work party. This realignment is important because each wheel can potentially take many tonnes weight, and can't be accessed once the Bridge is back on its turntable. The new cast bronze ring was fitted around the central pintle that is the pivot point for the bridge. Holes will be drilled and tapped for grease-nipples, allowing the the new collar to be lubricated in service. The threads of the rusty holding-down bolts on the NW plummer blocks were reclaimed and then new 1 1/4 British Standard Whitworth nuts were fitted. The thread had been developed by Joseph Whitworth in 1841, just eight years before Brunel designed the Swivel Bridge.June 2018
It was a sweltering hot day, so it was fortunate that the two main tasks were in the shade under the bridge. The new north-west turntable wheel was found to stand 20 mm above its neighbours, having been renewed with a new full-size casting. The original had worn and its supports had been raised on steel packers. The rusted nuts holding the bearing had to be freed with a gas torch borrowed from Dorothea Restorations (photo right), then the casting was lifted with a chain-hoist and the packers removed. The alignment was satisfactory after re-assembly. Rust was sanded from the turntable track-ring in readiness for painting. Half the little hut's south wall was painted a bright yellow, until the painters were beaten by the unrelenting heat of the scorching afternoon sun. May 2018Two new bronze bearings and a huge bronze ring, needed to get the bridge turning again, have been delivered by a local foundry. They will be sent to Croft Engineering for machining. A needle-gun was used to remove rust from the underside of the turntable, an unpleasant, arm-aching task that dropped rust in the workers' faces. The new bronzes were ground to fit their cast iron beds. The tarmac obstructing the tail-wheel track, was removed uncovering a 25mm step at a joint in the track.
April 2018The north-east wheel, which had been machined by Croft Engineering in Fishponds, was fitted. This involved removing the original bronze bearing shells, cleaning them, and then re-fitting the wheel. The photo on the right shows the wheel being moved across the top of the deck before being lowered into place. The plummer block of the south west wheel had to be realigned before the wheel could be refitted. Other Brunel's Swing Bridge PagesAs well as an introductory page, the other Brunel's Swing Bridge pages cover: events at the bridge, including the dates of work parties; reports of work parties in 2019, 2020, 2021, and 2022; photos of work parties in 2020, 2021, and 2022; information on the 170th Anniversary events; and copies of the display boards. Page updated 28 Mar 22 |
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