Brunel Swivel BridgeBrunel's Other Bridge

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Brunel Swivel Bridge Project 2017

Brunel Swivel Bridge
Investigative work on the rotation of the bridge 2017

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Preparation and Basic Conservation

The aim of the 2017 investigative work on the rotation of the bridge is to enable us to establish the following: These are essential investigative works that will significantly improve our understanding of the bridge in operation, the forces required to move it, and hence facilitate the design of the future drive-system, all of which will be required at HLF Stage 1.

Thus, the focus of the work in Phase 1 is to do the minimum amount of work to get the bridge into a condition in which it can turn a few times. Phase 1 comprises repairing the four support-wheels and the track supporting the bridge atop them, followed by lowering of the bridge and carrying out manual turning trials using hoists and load cells indicating the forces being applied.

The work-content will comprise the following and will be carried out by a combination of volunteers and specialist contractors during the period February to September 2017.

It is a concern that any hours we spend can not be counted as match funding until lottery funding has been granted. Work is limited since we are not allowed to start restoration work til we get our funding, so any work has to be investigative.

Volunteers still have useful work to do including clearing rust from inside the holed parts, inspecting interiors, measuring plate-thickness, fitting the timber stops, gardening, refitting the ram that was removed, clearing silt from pits, painting, etc.

Likely dates of work for 2017 (We will working 'one day per month' normally on SATURDAYS rather than a whole weekend):

Sounds like fun? No experience needed, all equipment provided, and you'll get really involved in helping to save Brunel's Other Bridge. We need your help.

Contact Geoff Wallis (jandgwallis@gmail.com) if you wish to help. We need to have an idea of numbers.

Overall Details of work

Funding

As you know, the Bridge is listed Grade 2* and is on Historic England (formerly English Heritage) Buildings at Risk Register. Whilst their funding is severely restricted, HE have been supportive in providing modest grants to carry out trials and erect a temporary roof, which were completed by Bristol City and Avon Industrial Buildings Trust with volunteer help last year.

EH/HE were impressed with the Mann Williams (MW) report that resulted from the grant-funded work that we managed on behalf of the council in 2015 and suggested that we discuss an application for further investigative work on critical areas identified in the report as part of this year's Heritage at Risk programme. They also suggested that we might request further assistance in other areas via their consultancy budget and service.

Contracts will be let by the Avon Industrial Buildings Trust and supervised by their Technical team, comprising Bob Watkins and Geoff Wallis.

We are delighted to see work by the professionals starting on site and want to thank Bristol City Council, English Heritage, the local amenity societies, our faithful hard-working volunteers, and huge number of supporters for getting the Project this far.

The big challenge lays ahead in securing major funding. We have a well-specified and costed scheme for repair which will form a sound basis for fund-raising.

You can make a donation using a charity website. The main donation link now uses the Wonderful fundraising website:
Brunel Swivel Bridge https://www.wonderful.org/charity/avonindustrialbuildingstrust

mydonate will stop working in June 2019

We have created a project on http://www.neighbourly.com to also help us fund raise for our HLF bid

or you can send a cheque payable to
Avon Industrial Buildings Trust to:
The Treasurer, Thatched Wells, Duckhole, Thornbury, BS35 1LD.

Leaflet giving information, asking for support and how to make a donation

Progress in 2017

October 2017

Our next Brunel Swivel Bridge work-day was Sunday 22nd October. Please note that this is a change from our usual third Saturday in the month.

We had a number of interesting tasks to carry out. We now have a shiny brand-new wheel to replace the worn out north east wheel, one of four that the 70 Tonne iron deck rotates on. Geoff shall be bringing this in his poor long-suffering estate car, but we then need to get it up onto the Bridge and install it! It is far too heavy to lift manually, so we shall have to be ingenious and use a hoist hung on 'sky-hooks'. If you have never seen 'sky-hooks' come along and you will be impressed!

Sal will be continuing with her survey of visitors passing through the site, and we have some serious gardening to do. A couple of self-seeded small trees need to be sawn down to prevent their roots from causing further damage to historic masonry walls, so please bring a bow-saw, axe if you have one, and lots of stamina.

Today a large team of helpers turned out in the sun and we achieved much. Sal recorded visitor numbers whilst others cut down some self-seeded saplings that were beginning to destabilize historic stonework, and David cleaned up the Council's shed where we store our equipment.

The challenging task of extracting the newly-made north west wheel from Geoff's groaning estate car and installing it under the turntable was achieved in a smooth operation lasting just three hours....not bad for a team of volunteers! Nowadays we are allowed legally to lift 25Kg, but the wheel weighed about 300 Kg. so we needed the correct equipment, and adopted 'ancient Egyptian' methods. First we erected our 'sky hook' which was a scaffold-tube frame stayed by webbing straps to form a simple derrick. The car was backed up to the derrick and a chain hoist used to extract the wheel and raise it to Bridge level. The derrick was then 'luffed' (leaned or lowered) to drop the wheel onto its specially-made frame. This was rolled on steel tubes along the Youngmans Boards to another derrick sited over the turntable, and lowered into place. It fitted well, but will be stiff in operation until the new surfaces bed in.

The whole operation was completed without scrapes, frights, or near-misses, a tribute to the expertise of Maggie, Darren, Ben, Ian, Chris, David, Bob and Geoff. 14 year old Charlie deserves a special mention for carefully operating our chain hoist and finally installing the wheel in its original bronze bearings, making sure that everything was clean, well-greased, and fitting properly. Well done Charlie, you were a real asset, and we hope your experience will serve you well as you start to think about your robotics career. Thank you too Martin (Charlie's Dad) for patiently acting as guardian.

Julian also deserves special thanks too for videoing the whole event. I have seen some of his videos and they are brilliant. See you all next workday when we hope to refit the SW wheel.

Photos of Progress in October 2017

September 2017

The Swivel Bridge Doors Open Day was a great success despite the variable weather which didn't seem to put hardy Brits off, with over 200 visitors being welcomed by volunteers Martyn, Sal, Ian, Rob, Mary S, Geoff, and David Greenfield, our engineering historian and BOB Technical Team member who came in specially from Taunton.

Interestingly our visitors came from all over, mostly from Bristol of course, but also from other parts of the UK, and even Russia, New Zealand, and Australia. An early visitor was a nine year old lad, an aspiring engineer who helped us lever up and lift off the heavy steel covers over the ram-pit. At the other end of the age range we were pleased to welcome Bristol's former Dock Engineer David Neale who recognized the importance of the Bridge when it became redundant in the 1960's and worked to save it from being scrapped.

We were encouraged by the general enthusiasm people showed for 'Rusty BOB', and by the two dozen new supporters who signed up to receive progress updates.

Our comprehensive display proved popular, showing masses of photographs, our giant 'mystery object' spanner, patterns for two turntable two bearings, and our enormous newly cast 250 Kg turntable wheel which was so heavy that it had to be left in the back of Geoff's groaning estate car for display.

Photos of Progress in September 2017

We plan to fit it on Sunday 22nd October, so why not come along and give us a hand? It should be fun, and we need lots of help on this and other tasks.'

August 2017

Saturday this week (19th August) is our next Brunel Swivel Bridge work-day, and we have several important tasks to complete: As always we meet at 10.00am at the Bridge. Plenty of parking space and basic toilets are available. Please wear stout footwear, and bring something to kneel on if 'gardening'. We have gloves, high-vis vests, etc. A number of our 'regulars' are away on holiday, so do come along and help if you can. Looking forward to working with you on Saturday.

Photos of Progress in August 2017

Holiday time is upon us so numbers were depleted today, but we successfully prepared everything for Doors Open day in three weeks time. David and Geoff cleared weeds, painted the big 'center-bolt spanner', and dealt with minor vandalism, whilst Maggie cleared out the base of the Bridge.

We had a slight diversion when Maggie's favourite hard hat blew off after emerging from under the sheltered space under the turntables. We managed to keep it close to the water side by means of a rope and bucket while Geoff made a grappling hook and rescued it.

Sal assisted by weeding underneath the deck whilst at the same time keeping her eyes open for visitors and completing the survey sheets....now, there's multi-tasking for you!'

Several interesting visitors, including a family from Ukraine who were really fascinated by BOB, and, of course left with a leaflet. Someone else come to talk about what mechanisms could be used to get the bridge turning again.

July 2017

Our next Brunel Swivel Bridge work-day is on Saturday this week (22nd).

During this session we shall be

For this could you please bring old clothes or coveralls, gardening gloves and kneeling pads, as we need to get into the ram-pits and right under the Bridge to clear the bed-castings, etc.

I think we can complete our tasks in half a day so I am proposing that we work from 10.00 am to 1.00pm on this occasion. We are awaiting a number of new components being made/machined off-site so once they arrive, hopefully in August, we shall have lots to do reassembling the new and restored parts.

Photos of Progress in July 2017

'Whilst the 'harbour-fest' was in full swing at the other end of the Floating Harbour, we had our own 'work-fest at Brunel's Other Bridge. Ian nobly carried out some much-needed clearing up under the Bridge in restricted space, and Martyn Hart investigated the flooded access pit, which we shall need to pump out in August.

Sal continued with the visitor survey and found that the harbour festival appeared to make no significant difference to the number of people crossing the Island.

One visiting family stopped by for a chat and proved to be really interesting folk. Martyn Wood's interests include history, engineering and Lego, and he has combined these into a fine Lego Brunel tattoo on his leg! Martin was a real sport and allowed us to photograph it.

After this excitement we all got down to a serious discussion on the details of how we planned to supply, protect, weld up, straighten, fix and seal a new steel cover-plate under the severely-corroded wrought iron original to provide a smooth, accurate running surface. We now have a sound plan, so we shall be very busy through the winter and into next spring both on site and off.'

June 2017

Our next Brunel Swivel Bridge work-day is on Saturday this week (17th) and we have some vital tasks to complete so your help would be greatly appreciated. (In fact, help will be essential!) Photos of Progress in June 2017 Our tasks today were clear and we carried them out with speed and efficiency despite the heat (25 degrees).

First Sal continued our survey of people visiting the Island to gauge the potential of the Bridge as a crossing. This was interesting since it was the first workday with the Ashton Bridge open to cyclists and pedestrians. There was a noticeable increase of people, and we had to add another category of 'shopping pedestrians' since several were laden with shopping after presumably shopping in Ashton.

Second we had to remove the four bronze bearings from the north west turntable wheel. The original wheel is severely worn so that we are having a new one made, and its shaft must be machined to fit the existing bearings. Bob, Martyn, Ian and Geoff are well-rehearsed in raising the wheel using a chain-hoist, and the 250Kg lump was lifted clear within half an hour of arriving on site. Then came the challenge of levering, wedging, hammering, and generally persuading the two bronzes out of their cast iron supports (called 'plummer blocks') which was difficult, cramped work, but satisfying once achieved, and no damage done to the brittle castings.
The two inner and two outer bearings will now go off to Boro Foundry in Stourbridge to have the new wheel-shaft fitted to them.

Maggie gallantly gardened and photographed whenever anything interesting happened, and our long-term volunteer video specialist Julian got some more important footage of all the activity. Oh, and of course we drank tea/coffee and chatted and watched the bridge swing twice and all the water sport! Thanks again folks for all your hard work.

May 2017

We meet for another work-day on Saturday this week 27th May so do please come and join us. We plan to: We meet at 10.00am at the Bridge. Please wear stout footwear and warm clothing if the weather changes, as is forecast.

Much of the activity now is off site. Boro Foundry at Stourbridge have made a wooden pattern for the new north-west turntable wheel, and this should be cast in a strong grade of iron shortly. Many thanks to the Cooperative Community Fund whose grant has made this extra work possible.

Geoff has made an aluminium pattern for the new bronzes needed for the south-west wheel, and four new bearing-halves have been cast. These are going to the machinists shortly, together with the original wheel itself whose shafts need to be skimmed to remove serious rust pitting.

Meanwhile at our workday on 27th Bob and Geoff turned their attention to the badly rusted 13ft diameter track which carries the weight of the Bridge on its turntable wheels. An experiment was carried out to dress back the pitted face using a big hand-held grinder, which proved successful. However, so much metal has to be removed that after much thought it was decided an easier option would be to place a temporary steel track over the existing one.


Careful measurements using plumb-bobs were carried out to determine the track's diameter. Bob found that following the measurements, he thought that he would put them on a record to compare with the original intended dimensions of the rail track.
The original Brunel drawings show a radius to the centreline of the rail track as 6ft 7.5in (79.5in). We are therefore very close when we average the N-S and E-W dimensions acquired on site today! which agreed almost exactly with the dimension given on the original drawing of the Bridge!
Achieving agreement between our dimensions and the original drawing dimension to within 60 thousandths of an inch must be coincidence: the plumb-bobs were swinging more than this in the wind!
Nevertheless, it gives us some confidence that the dimension is correct. Geoff will get a price for profile-cut 16mm plates, and check that HE are happy with this change of plan.

The track is an enormous wrought iron forging (about 14 ft diameter) probably made by rolling to a circle which must have been joined by fire-welding, ie, both ends being heated to bright-white heat and hammered together. Excitingly we believe we have located the joint, evidenced by diagonal lines in the working face, as can be seen on the photo. The forging is a complicated shape, remarkably accurate and a real tribute to the craftsmen who made it in 1849. We couldn't match this quality of manual forging nowadays.
It is an amazing example of heavy forge-work which should be preserved for future generations.
How did the blacksmiths make the track so accurately in the first place?

Sal continued with the survey of people crossing the site and, helped by Maggie carried out some much-needed tidying up, removing weeds and worse. Thank you ladies!' Photos of Progress in May 2017

April 2017

Our next work day is next Saturday, 22nd April so do please come and join us. We plan to: Today it was a lovely sunny day. We had two new people from Cliftonwood counting passers by and then Maggie took over. Mostly local people.
Bob, Martyn, Geoff, and David erected a scaffolding gantry, and lifted the north-west turntable wheel to meeasure it properly and then replaced it.

Photos of Progress in April 2017

March 2017

We meet at 10.00 am next Saturday 18th March at 'Brunel's Other Bridge to continue the following tasks: Today we made good progress in overcast windy conditions. Survey-supremo Sal carefully recorded numbers of passers, but not I think, our local saxophonist who entertained us just before the survey started.

Bob, Martyn, Geoff, Matt and David erected a scaffolding gantry, hoisted out the south-west turntable wheel and mounted it on a special steel trestle Geoff had made previously. Then came the challenge of getting it off the Bridge. It weighs 300Kg which is far too heavy to carry, so short scaffold tubes were used as rollers to propel it along a Youngman's board to the tail of the Bridge. The ancient Egyptians would have been proud of us!. The board was specially tested by several of the stouter members of the gang bouncing in the middle, which confirmed that a mid-span support would be needed for the long run from the Bridge down to Geoff's waiting car.

Loading the car involved juggling the cast iron turntable wheel off its rollers and onto the long board running into the back of the car, supported by a scaffold trestle to prevent it bending. When all was ready it was an easy task to wriggle the enormous casting down and into the car, although the suspension groaned somewhat!

The whole operation was photographed by Rebecca for her photo-blog, watch this space for its address. Bob continued his accurate measuring of the components, and shortly will complete the drawings needed for our machinist to make new parts.

At lunch time Maggie arrived with a throaty roar in her Moss motor (...errr., the car engine roared, not Maggie) and used her time usefully taking more photos and 'gardening' with Sal.

So, we now have the first major item off site and shortly start making new bearings. Exciting!

Photos of Progress in March 2017

February 2017

Our 2017 season of monthly volunteer work starts starts Saturday, 25th February, when we plan to: Our first volunteer day of the new year was 25th Feb, a month earlier than last year as we have so much to do.

Sal gallantly volunteered for doggie-doo-ty clearing up what inconsiderate owners allow their dogs to doo in our place of work. Thanks Sal, you are a star! Sal then carried out a survey of the cyclists and pedestrians passing across the Island, and had some interesting conversations. These statistics are needed to inform our plans for the Bridge by indicating the level of use it might get when restored, and we plan to continue the surveys each month, or more often if volunteers are forth-coming.

Angelo and Reece 'gardened', removing vegetation that had established itself around the site, and they continued faithfully when the rain started. Well done chaps.

Meanwhile, safe under our protective temporary roof Bob, Geoff, Ian, David and newcomer Matt removed rust from the turntable track and lifted off the heavy caps on the bearings of the wheels that the Bridge rotates on. We cleaned off old grease and checked the condition of the shafts that support the Bridge's 70 Tonnes. We decided two were too corroded for use and planned how to machine away the rust and fit new bearings.

We have been unsure how the four support wheels are fixed to their shaft but after much searching found a 'secret key' securing each, fitted in its hole so perfectly that they could hardly be seen! The engineers of 1849 did a spectacularly accurate job!

We were delighted to receive several visitors, including Warren Marsh from the Bristol Visual and Amenity Group, and Flavia De Luca with a lovely group of post-grads from the Department of Civil Engineering at Bristol University. Lets hope the forthcoming proposals for student projects find willing takers.

Photos of Progress in February 2017

Look at the reports page to see the summaries of the results of inspections of the bridge. Updated 11 January 2016

Photos of Progress in 2017

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